% % % % automatically generated % % ./bibtex2html -sort-criterium year -partial-equality-of-names -no-print-keywords options.bib u562pdf.bib % Date: Thu Jun 12 14:39:51 2008 % Author: cp983411 % % % @INCOLLECTION{Changeux2008, author = {Changeux, J.P., Dehaene, S.}, title = {The neuronal workspace model: conscious processing and learning}, booktitle = {Learning and Memory: A Comprehensive Reference}, publisher = {Elsevier}, year = {2008}, editor = {R.Menzel}, pdf = {http://www.unicog.org/publications/ChangeuxDehaene_ReviewChapterConsciousness_2008.pdf}, owner = {pallier}, timestamp = {2008.06.06} } @ARTICLE{Dehaene2008, author = {Stanislas Dehaene and Véronique Izard and Elizabeth Spelke and Pierre Pica}, title = {Log or linear? Distinct intuitions of the number scale in Western and Amazonian indigene cultures.}, journal = {Science}, year = {2008}, volume = {320}, pages = {1217--1220}, number = {5880}, month = {May}, abstract = {The mapping of numbers onto space is fundamental to measurement and to mathematics. Is this mapping a cultural invention or a universal intuition shared by all humans regardless of culture and education? We probed number-space mappings in the Mundurucu, an Amazonian indigene group with a reduced numerical lexicon and little or no formal education. At all ages, the Mundurucu mapped symbolic and nonsymbolic numbers onto a logarithmic scale, whereas Western adults used linear mapping with small or symbolic numbers and logarithmic mapping when numbers were presented nonsymbolically under conditions that discouraged counting. This indicates that the mapping of numbers onto space is a universal intuition and that this initial intuition of number is logarithmic. The concept of a linear number line appears to be a cultural invention that fails to develop in the absence of formal education.}, doi = {10.1126/science.1156540}, pdf = {http://www.unicog.org/publications/DehaeneIzardSpelkePica_LogLinearNumberSpaceMapping_Science2008.pdf}, institution = {INSERM, Cognitive Neuro-imaging Unit, Institut Fédératif de Recherche (IFR) 49, Gif sur Yvette, France. stanislas.dehaene@cea.fr}, owner = {pallier}, pii = {320/5880/1217}, pmid = {18511690}, timestamp = {2008.06.06}, url = {http://dx.doi.org/10.1126/science.1156540} } @ARTICLE{Dubois2008, author = {Jessica Dubois and Ghislaine Dehaene-Lambertz and Muriel Perrin and Jean-François Mangin and Yann Cointepas and Edouard Duchesnay and Denis Le Bihan and Lucie Hertz-Pannier}, title = {Asynchrony of the early maturation of white matter bundles in healthy infants: quantitative landmarks revealed noninvasively by diffusion tensor imaging.}, journal = {Hum Brain Mapp}, year = {2008}, volume = {29}, pages = {14--27}, number = {1}, month = {Jan}, abstract = {Normal cognitive development in infants follows a well-known temporal sequence, which is assumed to be correlated with the structural maturation of underlying functional networks. Postmortem studies and, more recently, structural MR imaging studies have described qualitatively the heterogeneous spatiotemporal progression of white matter myelination. However, in vivo quantification of the maturation phases of fiber bundles is still lacking. We used noninvasive diffusion tensor MR imaging and tractography in twenty-three 1-4-month-old healthy infants to quantify the early maturation of the main cerebral fascicles. A specific maturation model, based on the respective roles of different maturational processes on the diffusion phenomena, was designed to highlight asynchronous maturation across bundles by evaluating the time-course of mean diffusivity and anisotropy changes over the considered developmental period. Using an original approach, a progression of maturation in four relative stages was determined in each tract by estimating the maturation state and speed, from the diffusion indices over the infants group compared with an adults group on one hand, and in each tract compared with the average over bundles on the other hand. Results were coherent with, and extended previous findings in 8 of 11 bundles, showing the anterior limb of the internal capsule and cingulum as the most immature, followed by the optic radiations, arcuate and inferior longitudinal fascicles, then the spinothalamic tract and fornix, and finally the corticospinal tract as the most mature bundle. Thus, this approach provides new quantitative landmarks for further noninvasive research on brain-behavior relationships during normal and abnormal development.}, doi = {10.1002/hbm.20363}, pdf = {Rabrait_Evi_JMRI2008.pdf}, institution = {UNAF, Service Hospitalier Frédéric Joliot, CEA, Orsay, France. jessica.dubois@centraliens.net}, keywords = {Adult; Aging; Anisotropy; Cerebral Cortex; Corpus Callosum; Diffusion; Diffusion Magnetic Resonance Imaging; Female; Fornix, Brain; Humans; Infant; Internal Capsule; Male; Nerve Fibers, Myelinated; Neural Pathways; Pyramidal Tracts; Spinothalamic Tracts}, owner = {cp983411}, pmid = {17318834}, timestamp = {2008.06.12}, url = {http://dx.doi.org/10.1002/hbm.20363} } @ARTICLE{Dubois2008a, author = {Jessica Dubois and Ghislaine Dehaene-Lambertz and Catherine Soarès and Yann Cointepas and Denis Le Bihan and Lucie Hertz-Pannier}, title = {Microstructural correlates of infant functional development: example of the visual pathways.}, journal = {Journal of Neuroscience}, year = {2008}, volume = {28}, pages = {1943--1948}, number = {8}, month = {Feb}, abstract = {The development of cognitive functions during childhood relies on several neuroanatomical maturation processes. Among these processes is myelination of the white matter pathways, which speeds up electrical conduction. Quantitative indices of such structural processes can be obtained in vivo with diffusion tensor imaging (DTI), but their physiological significance remains uncertain. Here, we investigated the microstructural correlates of early functional development by combining DTI and visual event-related potentials (VEPs) in 15 one- to 4-month-old healthy infants. Interindividual variations of the apparent conduction speed, computed from the latency of the first positive VEP wave (P1), were significantly correlated with the infants' age and DTI indices measured in the optic radiations. This demonstrates that fractional anisotropy and transverse diffusivity are structural markers of functionally efficient myelination. Moreover, these indices computed along the optic radiations showed an early wave of maturation in the anterior region, with the posterior region catching up later in development, which suggests two asynchronous fronts of myelination in both the geniculocortical and corticogeniculate fibers. Thus, in addition to microstructural information, DTI provides noninvasive exquisite information on the functional development of the brain in human infants.}, doi = {10.1523/JNEUROSCI.5145-07.2008}, pdf = {http://www.unicog.org/publications/DuboisDehaeneHertzPannier_VisualParthway_JNS2008.pdf}, institution = {Unité de Neuroimagerie Anatomique et Fonctionnelle, Commissariat à l'Energie Atomique/Saclay/Division des Sciences du Vivant/Institut d'imagerie Biomédicale/Service Hospitalier Frédéric Joliot, 91401 Orsay, France. jessica.dubois@centraliens.net}, keywords = {Brain Mapping; Child Development; Diffusion Magnetic Resonance Imaging; Humans; Infant; Infant, Newborn; Neural Conduction; Neuronal Plasticity; Photic Stimulation; Visual Pathways}, owner = {cp983411}, pii = {28/8/1943}, pmid = {18287510}, timestamp = {2008.06.12}, url = {http://dx.doi.org/10.1523/JNEUROSCI.5145-07.2008} } @ARTICLE{Izard2008, author = {Véronique Izard and Ghislaine Dehaene-Lambertz and Stanislas Dehaene}, title = {Distinct cerebral pathways for object identity and number in human infants.}, journal = {PLoS Biology}, year = {2008}, volume = {6}, pages = {e11}, number = {2}, month = {Feb}, abstract = {All humans, regardless of their culture and education, possess an intuitive understanding of number. Behavioural evidence suggests that numerical competence may be present early on in infancy. Here, we present brain-imaging evidence for distinct cerebral coding of number and object identity in 3-mo-old infants. We compared the visual event-related potentials evoked by unforeseen changes either in the identity of objects forming a set, or in the cardinal of this set. In adults and 4-y-old children, number sense relies on a dorsal system of bilateral intraparietal areas, different from the ventral occipitotemporal system sensitive to object identity. Scalp voltage topographies and cortical source modelling revealed a similar distinction in 3-mo-olds, with changes in object identity activating ventral temporal areas, whereas changes in number involved an additional right parietoprefrontal network. These results underscore the developmental continuity of number sense by pointing to early functional biases in brain organization that may channel subsequent learning to restricted brain areas.}, doi = {10.1371/journal.pbio.0060011}, pdf = {http://www.unicog.org/publications/IzardDehaeneDehaene_NbObject_PlosBiology2008.pdf}, institution = {>}, owner = {cp983411}, pii = {07-PLBI-RA-2266}, pmid = {18254657}, timestamp = {2008.06.12}, url = {http://dx.doi.org/10.1371/journal.pbio.0060011} } @ARTICLE{Makni2008, author = {Salima Makni and Jérôme Idier and Thomas Vincent and Bertrand Thirion and Ghislaine Dehaene-Lambertz and Philippe Ciuciu}, title = {A fully Bayesian approach to the parcel-based detection-estimation of brain activity in fMRI.}, journal = {Neuroimage}, year = {2008}, volume = {41}, pages = {941--969}, number = {3}, month = {Jul}, abstract = {Within-subject analysis in fMRI essentially addresses two problems, i.e., the detection of activated brain regions in response to an experimental task and the estimation of the underlying dynamics, also known as the characterisation of Hemodynamic response function (HRF). So far, both issues have been treated sequentially while it is known that the HRF model has a dramatic impact on the localisation of activations and that the HRF shape may vary from one region to another. In this paper, we conciliate both issues in a region-based joint detection-estimation framework that we develop in the Bayesian formalism. Instead of considering function basis to account for spatial variability, spatially adaptive General Linear Models are built upon region-based non-parametric estimation of brain dynamics. Regions are first identified as functionally homogeneous parcels in the mask of the grey matter using a specific procedure [Thirion, B., Flandin, G., Pinel, P., Roche, A., Ciuciu, P., Poline, J.-B., August 2006. Dealing with the shortcomings of spatial normalization: Multi-subject parcellation of fMRI datasets. Hum. Brain Mapp. 27 (8), 678-693.]. Then, in each parcel, prior information is embedded to constrain this estimation. Detection is achieved by modelling activating, deactivating and non-activating voxels through mixture models within each parcel. From the posterior distribution, we infer upon the model parameters using Markov Chain Monte Carlo (MCMC) techniques. Bayesian model comparison allows us to emphasize on artificial datasets first that inhomogeneous gamma-Gaussian mixture models outperform Gaussian mixtures in terms of sensitivity/specificity trade-off and second that it is worthwhile modelling serial correlation through an AR(1) noise process at low signal-to-noise (SNR) ratio. Our approach is then validated on an fMRI experiment that studies habituation to auditory sentence repetition. This phenomenon is clearly recovered as well as the hierarchical temporal organisation of the superior temporal sulcus, which is directly derived from the parcel-based HRF estimates.}, doi = {10.1016/j.neuroimage.2008.02.017}, pdf = {MakniCiuciu_ParcellesPhrases_Neuroimg2008.pdf}, institution = {Oxford Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), University of Oxford, John Radcliffe Hospital, Oxford, UK.}, owner = {cp983411}, pii = {S1053-8119(08)00129-8}, pmid = {18439839}, timestamp = {2008.06.12}, url = {http://dx.doi.org/10.1016/j.neuroimage.2008.02.017} } @ARTICLE{Rabrait2008, author = {Cécile Rabrait and Philippe Ciuciu and Alejandro Ribés and Cyril Poupon and Patrick Le Roux and Ghislaine Dehaine-Lambertz and D. Le Bihan and F. Lethimonnier}, title = {High temporal resolution functional MRI using parallel echo volumar imaging.}, journal = {J Magn Reson Imaging}, year = {2008}, volume = {27}, pages = {744--753}, number = {4}, month = {Apr}, abstract = {PURPOSE: To combine parallel imaging with 3D single-shot acquisition (echo volumar imaging, EVI) in order to acquire high temporal resolution volumar functional MRI (fMRI) data. MATERIALS AND METHODS: An improved EVI sequence was associated with parallel acquisition and field of view reduction in order to acquire a large brain volume in 200 msec. Temporal stability and functional sensitivity were increased through optimization of all imaging parameters and Tikhonov regularization of parallel reconstruction. Two human volunteers were scanned with parallel EVI in a 1.5T whole-body MR system, while submitted to a slow event-related auditory paradigm. RESULTS: Thanks to parallel acquisition, the EVI volumes display a low level of geometric distortions and signal losses. After removal of low-frequency drifts and physiological artifacts, activations were detected in the temporal lobes of both volunteers and voxelwise hemodynamic response functions (HRF) could be computed. On these HRF different habituation behaviors in response to sentence repetition could be identified. CONCLUSION: This work demonstrates the feasibility of high temporal resolution 3D fMRI with parallel EVI. Combined with advanced estimation tools, this acquisition method should prove useful to measure neural activity timing differences or study the nonlinearities and nonstationarities of the BOLD response.}, doi = {10.1002/jmri.21329}, pdf = {Rebrait_Evi_JMRI2008.pdf}, institution = {CEA/DSV/I 2 BM/Neurospin, Gif-sur-Yvette, France. cecile.rabrait@ambre.net}, owner = {cp983411}, pmid = {18383267}, timestamp = {2008.06.12}, url = {http://dx.doi.org/10.1002/jmri.21329} } @ARTICLE{Sackur2008, author = {Sackur,Jerome and Naccache,Lionel and Pradat-Diehl,Pascale and Azouvi,Philippe and Mazevet,Dominique and Katz,Rose and Cohen,Laurent and Dehaene,Stanislas}, title = {Semantic processing of neglected numbers}, journal = {Cortex}, year = {2008}, volume = {In Press,Corrected Proof}, abstract = {While neglected stimuli can still be processed,few studies have directly addressed the issue of the unconscious access to semantics. In order to clarify this issue,we engaged four patients with unilateral left spatial neglect in a number comparison task. Each target number was preceded by a lateralized number prime,either in the intact or neglected hemifield (HF). Both group analyses and the intensive study of a single patient show that left (neglected) as well as right (consciously perceived) number primes affect performance: primes representing quantities that fall on the same side of the reference as the target lead to faster categorization. This congruency effect is highly suggestive of numerical semantic processing of neglected stimuli. Absence of conscious perception of neglected primes was evaluated using a combination of subjective and objective measures of performance in forced-choice tasks.}, pdf = {http://www.unicog.org/publications/Sackur2008.pdf}, keywords = {Left hemineglect,Unconscious semantics,Number comparison}, nstandard = {/home/jerome/articles/sackur/Sackur2008.pdf}, owner = {chrplr}, timestamp = {2008.04.12}, url = {http://www.sciencedirect.com/science/article/B8JH1-4RDR1M8-12/2/c3e80a1c5a1b72d6a39386286ec5299a} } @ARTICLE{Sigman2008, author = {Sigman,Mariano and Sackur,Jérôme and Del Cul,Antoine and Dehaene,Stanislas}, title = {Illusory displacement due to object substitution near the consciousness threshold}, journal = {Journal of Vision}, year = {2008}, volume = {8}, pages = {1?10}, number = {1}, abstract = {A briefly presented target shape can be made invisible by the subsequent presentation of a mask that replaces the target. While varying the target–mask interval in order to investigate perception near the consciousness threshold,we discovered a novel visual illusion. At some intervals,the target is clearly visible,but its location is misperceived. By manipulating the mask's size and target's position,we demonstrate that the perceived target location is always displaced to the boundary of a virtual surface defined by the mask contours. Thus,mutual exclusion of surfaces appears as a cause of masking.}, pdf = {http://www.unicog.org/publications/Sackur2008.pdf}, keywords = {visual illusion,masking,feature inheritance,top-down,surface,gestalt,binding,illusory conjunction,object substitution}, nstandard = {/home/jerome/articles/sackur/Sigman2008.pdf}, owner = {chrplr}, timestamp = {2008.04.12}, url = {http://journalofvision.org/8/1/13/} } @INBOOK{Dehaene2007c, chapter = {2}, pages = {1-29}, title = {Conscious and non-conscious processes: Distinct forms of evidence accumulation?}, year = {2007}, author = {Stanislas Dehaene}, pdf = {http://www.unicog.org/publications/Dehaene_ConsciousNonConsciousAccumulation_StrungmannForumChapter2007.pdf}, owner = {sd983141}, timestamp = {2008.01.03} } @INCOLLECTION{Dehaene2007, author = {Stanislas Dehaene}, title = {Symbols and quantities in parietal cortex: elements of a mathematical theory of number representation and manipulation}, booktitle = {Sensorimotor foundations of higher cognition.}, publisher = {Harvard University Press}, year = {2007}, editor = {Patrick Haggard and Yves Rossetti and Mitsuo Kawato}, volume = {XXII}, series = {Attention and Performance}, chapter = {24}, pages = {527-574}, pdf = {http://www.unicog.org/publications/Dehaene_SymbolsQuantitiesMathematicalTheory_ChapterAttPerf2007.pdf}, owner = {sd983141}, timestamp = {2008.01.03} } @INCOLLECTION{Pallier2007, author = {Christophe Pallier}, title = {Critical periods in language acquisition and language attrition}, booktitle = {Language Attrition: Theoretical perspectives}, publisher = {John Benjamins}, year = {2007}, editor = {Köpke, Barbara and Schmid, Monika S. and Keijzer, Merel and Dostert, Susan}, address = {Amsterdam}, pdf = {http://www.pallier.org/papers/Pallier.critical.period.attrition.chapter.2007.pdf}, owner = {chrplr}, timestamp = {2007.06.05} } @INCOLLECTION{Poline2007, author = {Jean-Baptiste Poline and Ferath Kherif and Christophe Pallier and Will Penny}, title = {Contrasts and Classical Inference}, booktitle = {Statistical Parameter Mapping}, publisher = {Elsevier}, year = {2007}, editor = {Karl Friston}, owner = {chrplr}, timestamp = {2007.03.05} } @INCOLLECTION{Wilson2007, author = {Wilson, Anna Juliet and Dehaene, Stanislas}, title = {Number sense and developmental dyscalculia}, booktitle = {Human behavior, learning and the developing brain: Atypical development}, publisher = {Guilford Press}, year = {2007}, editor = {Coch, Donna and Dawson, Geraldine and Fischer, Kurt}, address = {New York}, abstract = {In this chapter we review the possible biological bases for developmental dyscalculia, which is a disorder in mathematical abilities presumed to be due to impaired brain function. By reviewing what is known about the localization of numerical cognition functions in the adult brain, the causes of acquired dyscalculia, and the normal development of numerical cognition, we propose several hypotheses for causes of developmental dyscalculia, including that of a core deficit of "number sense" related to an impairment in the horizontal intra- parietal sulcus (HIPS) area. We then discuss research on dyscalculia, including the contribution of recent imaging results in special populations, and evaluate to what extent this research supports our hypotheses. We conclude that there is promising preliminary evidence for a core deficit of number sense in dyscalculia, but we also emphasize that more research is needed to test the hypothesis of multiple types of dyscalculia, particularly in the area of dyscalculia subtyping. We complete the chapter with a discussion of future directions to be taken, the implications for education, and the construction of number sense remediation software in our laboratory.}, pdf = {http://www.unicog.org/publications/WilsonDehaene_inPress_Final_HBDB.pdf}, } @ARTICLE{Andress2007inpress, author = {Andress, A and Dehaene-Lambertz,G. and Mehler, J.}, title = {Perceptual constraints and the learnability of simple grammars}, journal = {Cognition}, year = {2007, in press}, pdf = {http://www.unicog.org/publications/Andress-Dehaene-LambertzMehler_Perceptual_Constraints_And_Learnability_Cognition2007.pdf}, owner = {chrplr}, timestamp = {2007.02.13} } @ARTICLE{Dehaene2007d, author = {Stanislas Dehaene and Laurent Cohen}, title = {Response to Carreiras et al: The role of visual similarity, feedforward, feedback and lateral pathways in reading.}, journal = {Trends Cogn Sci}, year = {2007}, volume = {11}, pages = {456--457}, number = {11}, month = {Nov}, doi = {10.1016/j.tics.2007.08.009}, pdf = {http://www.unicog.org/publications/DehaeneCohen_FeedforwardFeedbackReadingResponseToCarreiras_TICS2007.pdf}, institution = {Institut National de la Santé et de la Recherche Médicale, U562, Cognitive Neuroimaging Unit, F-91191 Gif/Yvette, France; Commissariat à l?Energie Atomique, DSV/I2BM, NeuroSpin Center, F-91191 Gif/Yvette, France; Université Paris-Sud, IFR49, F-91191 Gif/Yvette, France; Collège de France, F-75005 Paris, France.}, owner = {sd983141}, pii = {S1364-6613(07)00243-4}, pmid = {17981073}, timestamp = {2008.01.03}, url = {http://dx.doi.org/10.1016/j.tics.2007.08.009} } @ARTICLE{Dehaene2007b, author = {Stanislas Dehaene and Laurent Cohen}, title = {Cultural recycling of cortical maps.}, journal = {Neuron}, year = {2007}, volume = {56}, pages = {384--398}, number = {2}, month = {Oct}, abstract = {Part of human cortex is specialized for cultural domains such as reading and arithmetic, whose invention is too recent to have influenced the evolution of our species. Representations of letter strings and of numbers occupy reproducible locations within large-scale macromaps, respectively in the left occipito-temporal and bilateral intraparietal cortex. Furthermore, recent fMRI studies reveal a systematic architecture within these areas. To explain this paradoxical cerebral invariance of cultural maps, we propose a neuronal recycling hypothesis, according to which cultural inventions invade evolutionarily older brain circuits and inherit many of their structural constraints.}, doi = {10.1016/j.neuron.2007.10.004}, pdf = {http://www.unicog.org/publications/DehaeneCohen_CulturalRecyclingCorticalMaps_Neuron2007.pdf}, institution = {INSERM, Cognitive Neuro-imaging Unit, IFR 49, Gif sur Yvette, France. stanislas.dehaene@cea.fr}, keywords = {Brain Mapping; Cerebral Cortex; Culture; Humans; Magnetic Resonance Imaging; Models, Anatomic; Models, Neurological; Neurons; Reading}, owner = {sd983141}, pii = {S0896-6273(07)00759-3}, pmid = {17964253}, timestamp = {2008.01.03}, url = {http://dx.doi.org/10.1016/j.neuron.2007.10.004} } @ARTICLE{Dehaene2007a, author = {Stanislas Dehaene}, title = {A few steps toward a science of mental life}, journal = {Mind, Brain, and Education}, year = {2007}, volume = {1}, pdf = {http://www.unicog.org/publications/Dehaene_StepsTowardsScienceMentalLife_MBE2007.pdf}, owner = {sd983141}, timestamp = {2008.01.03} } @ARTICLE{Del2007, author = {Del Cul, Antoine and Sylvain Baillet and Stanislas Dehaene}, title = {Brain dynamics underlying the nonlinear threshold for access to consciousness.}, journal = {PLoS Biol}, year = {2007}, volume = {5}, pages = {e260}, number = {10}, month = {Oct}, abstract = {When a flashed stimulus is followed by a backward mask, subjects fail to perceive it unless the target-mask interval exceeds a threshold duration of about 50 ms. Models of conscious access postulate that this threshold is associated with the time needed to establish sustained activity in recurrent cortical loops, but the brain areas involved and their timing remain debated. We used high-density recordings of event-related potentials (ERPs) and cortical source reconstruction to assess the time course of human brain activity evoked by masked stimuli and to determine neural events during which brain activity correlates with conscious reports. Target-mask stimulus onset asynchrony (SOA) was varied in small steps, allowing us to ask which ERP events show the characteristic nonlinear dependence with SOA seen in subjective and objective reports. The results separate distinct stages in mask-target interactions, indicating that a considerable amount of subliminal processing can occur early on in the occipito-temporal pathway (<250 ms) and pointing to a late (>270 ms) and highly distributed fronto-parieto-temporal activation as a correlate of conscious reportability.}, doi = {10.1371/journal.pbio.0050260}, pdf = {http://www.unicog.org/publications/DelculBailletDehaene_BrainDynamicsConsciousThreshold_PLOSbiol2007screenpdf.pdf}, institution = {INSERM, Cognitive Neuroimaging Unit, IFR 49, Saclay, France. antoine.delcul@cea.fr}, keywords = {Adult; Brain; Consciousness; Female; Humans; Male; Nonlinear Dynamics; Perceptual Masking; Photic Stimulation; Reaction Time; Sensory Thresholds; Visual Perception}, owner = {sd983141}, pii = {07-PLBI-RA-0389}, pmid = {17896866}, timestamp = {2008.01.03}, url = {http://dx.doi.org/10.1371/journal.pbio.0050260} } @ARTICLE{Gaillard2007, author = {Raphaël Gaillard and Laurent Cohen and Claude Adam and Stéphane Clemenceau and Dominique Hasboun and Michel Baulac and Jean-Claude Willer and Stanislas Dehaene and Lionel Naccache}, title = {Subliminal words durably affect neuronal activity.}, journal = {Neuroreport}, year = {2007}, volume = {18}, pages = {1527--1531}, number = {15}, month = {Oct}, abstract = {Unconscious mental representations elicited by subliminal stimuli are marked by their fleeting lifetimes, usually below 1 s. Can such evanescent subliminal stimuli, nevertheless, lead to long-lasting learning? To date, evidence suggesting a long-term influence of briefly perceived stimuli on behaviour or brain activity is scarce and questionable. In this study, we used intracranial recordings to provide the first direct demonstration that unconsciously perceived subliminal words could exert long-lasting effects on neuronal signals. When repeating subliminal words over long interstimulus intervals, we observed electrophysiological repetition effects. These unconscious repetition effects suggest that the single presentation of a masked word can durably affect neural architecture.}, doi = {10.1097/WNR.0b013e3282f0b6cd}, pdf = {http://www.unicog.org/publications/GaillardNaccache_DurableEffectSubliminalWords_Neuroreport_2007.pdf}, institution = { University Pierre et Marie Curie, Paris, France.}, keywords = {Adult; Discrimination (Psychology); Electrodes, Implanted; Electrophysiology; Epilepsy; Evoked Potentials, Auditory; Female; Humans; Male; Middle Aged; Monte Carlo Method; Neurons; Patch-Clamp Techniques; Reaction Time; Speech Perception; Subliminal Stimulation}, owner = {sd983141}, pii = {00001756-200710080-00004}, pmid = {17885595}, timestamp = {2008.01.03}, url = {http://dx.doi.org/10.1097/WNR.0b013e3282f0b6cd} } @ARTICLE{Giraud2007, author = {Anne-Lise Giraud and Andreas Kleinschmidt and David Poeppel and Torben E Lund and Richard S J Frackowiak and Helmut Laufs}, title = {Endogenous cortical rhythms determine cerebral specialization for speech perception and production.}, journal = {Neuron}, year = {2007}, volume = {56}, pages = {1127--1134}, number = {6}, month = {Dec}, abstract = {Across multiple timescales, acoustic regularities of speech match rhythmic properties of both the auditory and motor systems. Syllabic rate corresponds to natural jaw-associated oscillatory rhythms, and phonemic length could reflect endogenous oscillatory auditory cortical properties. Hemispheric lateralization for speech could result from an asymmetry of cortical tuning, with left and right auditory areas differentially sensitive to spectro-temporal features of speech. Using simultaneous electroencephalographic (EEG) and functional magnetic resonance imaging (fMRI) recordings from humans, we show that spontaneous EEG power variations within the gamma range (phonemic rate) correlate best with left auditory cortical synaptic activity, while fluctuations within the theta range correlate best with that in the right. Power fluctuations in both ranges correlate with activity in the mouth premotor region, indicating coupling between temporal properties of speech perception and production. These data show that endogenous cortical rhythms provide temporal and spatial constraints on the neuronal mechanisms underlying speech perception and production.}, doi = {10.1016/j.neuron.2007.09.038}, pdf = {http://www.unicog.org/publications/Giraud_neuron_2007.pdf}, institution = {Inserm, U742, Paris, F-75005, France. anne-lise.giraud@ens.fr}, keywords = {Acoustic Stimulation; Adult; Auditory Cortex; Brain Mapping; Electroencephalography; Female; Functional Laterality; Humans; Image Processing, Computer-Assisted; Male; Oxygen; Periodicity; Production Measurement; Reaction Time; Spectrum Analysis; Speech; Speech ; Speech Perception}, owner = {chrplr}, pii = {S0896-6273(07)00816-1}, pmid = {18093532}, timestamp = {2008.04.10}, url = {http://dx.doi.org/10.1016/j.neuron.2007.09.038} } @ARTICLE{Golestani2007, author = {Narly Golestani and Nicolas Molko and Stanislas Dehaene and Denis Lebihan and Christophe Pallier}, title = {Brain structure predicts the learning of foreign speech sounds.}, journal = {Cereb Cortex}, year = {2007}, volume = {17}, pages = {575--582}, number = {3}, month = {Mar}, abstract = {Previous work has shown a relationship between parietal lobe anatomy and nonnative speech sound learning. We scanned a new group of phonetic learners using structural magnetic resonance imaging and diffusion tensor imaging. Voxel-based morphometry indicated higher white matter (WM) density in left Heschl's gyrus (HG) in faster compared with slower learners, and manual segmentation of this structure confirmed that the WM volume of left HG is larger in the former compared with the latter group. This finding was replicated in a reanalysis of the original groups tested in Golestani and others (2002, Anatomical correlates of learning novel speech sounds. Neuron 35:997-1010). We also found that faster learners have a greater asymmetry (left > right) in parietal lobe volumes than slower learners and that the right insula and HG are more superiorly located in slower compared with faster learners. These results suggest that left auditory cortex WM anatomy, which likely reflects auditory processing efficiency, partly predicts individual differences in an aspect of language learning that relies on rapid temporal processing. It also appears that a global displacement of components of a right hemispheric language network, possibly reflecting individual differences in the functional anatomy and lateralization of language processing, is predictive of speech sound learning.}, doi = {10.1093/cercor/bhk001}, pdf = {http://www.pallier.org/papers/Golestani_HG_CerCor_2006.pdf}, owner = {chrplr}, pii = {bhk001}, pmid = {16603709}, timestamp = {2007.02.22}, url = {http://dx.doi.org/10.1093/cercor/bhk001} } @ARTICLE{Golestani2007a, author = {Narly Golestani and Christophe Pallier}, title = {Anatomical correlates of foreign speech sound production}, journal = {Cereb Cortex}, year = {2007}, volume = {17}, pages = {929--934}, number = {4}, month = {Apr}, abstract = {Previous work has shown a relationship between brain anatomy and how quickly adults learn to perceive foreign speech sounds. Faster learners have greater asymmetry (left > right) in parietal lobe white matter (WM) volumes and larger WM volumes of left Heschl's gyrus than slower learners. Here, we tested native French speakers who were previously scanned using high-resolution anatomical magnetic resonance imaging. We asked them to pronounce a Persian consonant that does not exist in French but which can easily be distinguished from French speech sounds, the voiced uvular stop. Two judges scored the goodness of the utterances. Voxel-based morphometry revealed that individuals who more accurately pronounce the foreign sound have higher WM density in the left insula/prefrontal cortex and in the inferior parietal cortices bilaterally compared with poorer producers. Results suggest that WM anatomy in brain regions previously implicated in articulation and phonological working memory, or the size/shape of these or adjacent regions, is in part predictive of the accuracy of speech sound pronunciation.}, doi = {10.1093/cercor/bhl003}, pdf = {http://www.pallier.org/papers/GolestaniPallier.Anatomy.SpeechProduction.2006.pdf}, owner = {chrplr}, pii = {bhl003}, pmid = {16740583}, timestamp = {2007.03.14}, url = {http://dx.doi.org/10.1093/cercor/bhl003} } @ARTICLE{Hein2007, author = {Grit Hein and Arjen Alink and Andreas Kleinschmidt and Notger G Müller}, title = {Competing neural responses for auditory and visual decisions.}, journal = {PLoS ONE}, year = {2007}, volume = {2}, pages = {e320}, abstract = {Why is it hard to divide attention between dissimilar activities, such as reading and listening to a conversation? We used functional magnetic resonance imaging (fMRI) to study interference between simple auditory and visual decisions, independently of motor competition. Overlapping activity for auditory and visual tasks performed in isolation was found in lateral prefrontal regions, middle temporal cortex and parietal cortex. When the visual stimulus occurred during the processing of the tone, its activation in prefrontal and middle temporal cortex was suppressed. Additionally, reduced activity was seen in modality-specific visual cortex. These results paralleled impaired awareness of the visual event. Even without competing motor responses, a simple auditory decision interferes with visual processing on different neural levels, including prefrontal cortex, middle temporal cortex and visual regions.}, doi = {10.1371/journal.pone.0000320}, pdf = {http://www.unicog.org/publications/Hein.plos.2007.pdf}, owner = {chrplr}, pmid = {17389911}, timestamp = {2007.04.05}, url = {http://dx.doi.org/10.1371/journal.pone.0000320} } @ARTICLE{Izard2007, author = {Véronique Izard and Stanislas Dehaene}, title = {Calibrating the mental number line.}, journal = {Cognition}, year = {2007}, month = {Aug}, abstract = {Human adults are thought to possess two dissociable systems to represent numbers: an approximate quantity system akin to a mental number line, and a verbal system capable of representing numbers exactly. Here, we study the interface between these two systems using an estimation task. Observers were asked to estimate the approximate numerosity of dot arrays. We show that, in the absence of calibration, estimates are largely inaccurate: responses increase monotonically with numerosity, but underestimate the actual numerosity. However, insertion of a few inducer trials, in which participants are explicitly (and sometimes misleadingly) told that a given display contains 30 dots, is sufficient to calibrate their estimates on the whole range of stimuli. Based on these empirical results, we develop a model of the mapping between the numerical symbols and the representations of numerosity on the number line.}, doi = {10.1016/j.cognition.2007.06.004}, pdf = {http://www.unicog.org/publications/IzardDehaene_NumerosityNamingCalibration_Cognition2007.pdf}, institution = {Department of Psychology, Harvard University, 33 Kirkland Street, Cambridge, MA 02138, USA; INSERM, U562, Cognitive Neuroimaging Unit, F-91191 Gif/Yvette, France; CEA, DSV/12BM, NeuroSpin Center, F-91191 Gif/Yvette, France.}, owner = {sd983141}, pii = {S0010-0277(07)00156-4}, pmid = {17678639}, timestamp = {2008.01.03}, url = {http://dx.doi.org/10.1016/j.cognition.2007.06.004} } @ARTICLE{Kleinschmidt2007a, author = {Andreas Kleinschmidt}, title = {Different analysis solutions for different spatial resolutions? Moving towards a mesoscopic mapping of functional architecture in the human brain.}, journal = {Neuroimage}, year = {2007}, volume = {38}, pages = {663--665}, number = {4}, month = {Dec}, abstract = {This comment challenges the dichtotomy that Kriegeskorte and Bandettini (this issue) propose to exist between "activation-based" and "information-based" approaches to fMRI analyses and argues that multi-variate analyses are just a special case within the overall repertoire of methods for analyzing paradigm-related BOLD signal variations. Moreover, this comment argues that using multi-variate approaches comes at a price, trading-off spatial resolution for sensitivity, and thus partially cancels potential benefits from high-field fMRI. Paradoxically, this comment thus concludes that pattern analyses provide a powerful complement to existing methods but not the complement that will actually permit to map functional architecture at mesoscopic resolution, i.e., one of the most interesting applications of high-field fMRI.}, doi = {10.1016/j.neuroimage.2007.03.047}, pdf = {http://www.unicog.org/publications/Kleinschmidt_nimg_comment_2007.pdf}, institution = {INSERM, Unité 562, F-91191 Gif-sur-Yvette, France. andreas.kleinschmidt@cea.fr}, keywords = {Analysis of Variance; Brain; Brain Mapping; Humans; Image Processing, Computer-Assisted; Information Theory; Magnetic Resonance Imaging; Oxygen}, owner = {chrplr}, pii = {S1053-8119(07)00280-7}, pmid = {17765573}, timestamp = {2008.04.10}, url = {http://dx.doi.org/10.1016/j.neuroimage.2007.03.047} } @ARTICLE{Kleinschmidt2007, author = {Andreas Kleinschmidt}, title = {Incidental neuroimaging findings: lessons from brain research in volunteers.}, journal = {Curr Opin Neurol}, year = {2007}, volume = {20}, pages = {387--389}, number = {4}, month = {Aug}, doi = {10.1097/WCO.0b013e3282294810}, pdf = {http://www.unicog.org/publications/Kleinschmidt_con_comment_2007.pdf}, keywords = {Bioethics; Brain; Human Experimentation; Humans; Incidental Findings; Research Subjects}, owner = {chrplr}, pii = {00019052-200708000-00003}, pmid = {17620871}, timestamp = {2008.04.10}, url = {http://dx.doi.org/10.1097/WCO.0b013e3282294810} } @ARTICLE{Kouider2007, author = {Sid Kouider and Stanislas Dehaene}, title = {Levels of processing during non-conscious perception: a critical review of visual masking.}, journal = {Philos Trans R Soc Lond B Biol Sci}, year = {2007}, volume = {362}, pages = {857--875}, number = {1481}, month = {May}, abstract = {Understanding the extent and limits of non-conscious processing is an important step on the road to a thorough understanding of the cognitive and cerebral correlates of conscious perception. In this article, we present a critical review of research on subliminal perception during masking and other related experimental conditions. Although initially controversial, the possibility that a broad variety of processes can be activated by a non-reportable stimulus is now well established. Behavioural findings of subliminal priming indicate that a masked word or digit can have an influence on perceptual, lexical and semantic levels, while neuroimaging directly visualizes the brain activation that it evokes in several cortical areas. This activation is often attenuated under subliminal presentation conditions compared to consciously reportable conditions, but there are sufficiently many exceptions, in paradigms such as the attentional blink, to indicate that high activation, per se, is not a sufficient condition for conscious access to occur. We conclude by arguing that for a stimulus to reach consciousness, two factors are jointly needed: (i) the input stimulus must have enough strength (which can be prevented by masking) and (ii) it must receive top-down attention (which can be prevented by drawing attention to another stimulus or task). This view leads to a distinction between two types of non-conscious processes, which we call subliminal and preconscious. According to us, maintaining this distinction is essential in order to make sense of the growing neuroimaging data on the neural correlates of consciousness.}, doi = {10.1098/rstb.2007.2093}, pdf = {http://www.unicog.org/publications/KouiderDehaene_ReviewSubliminalProcessing_ProcRoySoc2007.pdf}, keywords = {Attention; Brain; Consciousness; Humans; Neuropsychology; Perception; Perceptual Masking; Semantics; Unconscious (Psychology)}, owner = {chrplr}, pii = {Q8G05208M6626H04}, pmid = {17403642}, timestamp = {2007.06.27}, url = {http://dx.doi.org/10.1098/rstb.2007.2093} } @ARTICLE{McCrink2007, author = {Koleen McCrink and Stanislas Dehaene and Ghislaine Dehaene-Lambertz}, title = {Moving along the number line: operational momentum in nonsymbolic arithmetic.}, journal = {Percept Psychophys}, year = {2007}, volume = {69}, pages = {1324--1333}, number = {8}, month = {Nov}, abstract = {Can human adults perform arithmetic operations with large approximate numbers, and what effect, if any, does an internal spatial-numerical representation of numerical magnitude have on their responses? We conducted a psychophysical study in which subjects viewed several hundred short videos of sets of objects being added or subtracted from one another and judged whether the final numerosity was correct or incorrect. Over a wide range of possible outcomes, the subjects' responses peaked at the approximate location of the true numerical outcome and gradually tapered off as a function of the ratio of the true and proposed outcomes (Weber's law). Furthermore, an operational momentum effect was observed, whereby addition problems were overestimated and subtraction problems were underestimated. The results show that approximate arithmetic operates according to precise quantitative rules, perhaps analogous to those characterizing movement on an internal continuum.}, pdf = {http://www.unicog.org/publications/McCrinkDehaeneDehaeneLambertz_OperationalMomentum_PP2007.pdf}, institution = {Department of Psychology, Harvard University, Cambridge, Massachusetts 02138, USA. mccrink@wjh.harvard.edu}, owner = {sd983141}, pmid = {18078224}, timestamp = {2008.01.03} } @ARTICLE{Mueller2007, author = {Notger G Müller and Andreas Kleinschmidt}, title = {Temporal dynamics of the attentional spotlight: neuronal correlates of attentional capture and inhibition of return in early visual cortex.}, journal = {J Cogn Neurosci}, year = {2007}, volume = {19}, pages = {587--593}, number = {4}, month = {Apr}, abstract = {A stimulus that suddenly appears in the corner of the eye inevitably captures our attention, and this in turn leads to faster detection of a second stimulus presented at the same position shortly thereafter. After about 250 msec, however, this effect reverses and the second stimulus is detected faster when it appears far away from the first. Here, we report a potential physiological correlate of this time-dependent attentional facilitation and inhibition. We measured the activity in visual cortex representations of the second (target) stimulus' location depending on the stimulus onset asynchrony (SOA) and spatial distance that separated the target from the preceding cue stimulus. At an SOA of 100 msec, the target yielded larger responses when it was presented near to than far away from the cue. At an SOA of 850 msec, however, the response to the target was more pronounced when it appeared far away from the cue. Our data show how the neural substrate of visual orienting is guided by immediately preceding sensory experience and how a fast-reacting brain system modulates sensory processing by briefly increasing and subsequently decreasing responsiveness in parts of the visual cortex. We propose these activity modulations as the neural correlate of the sequence of perceptual facilitation and inhibition after attentional capture.}, doi = {10.1162/jocn.2007.19.4.587}, pdf = {http://www.unicog.org/publications/Muller.Kleinschmidt.jocn.2007.pdf}, owner = {chrplr}, pmid = {17381250}, timestamp = {2007.03.29}, url = {http://dx.doi.org/10.1162/jocn.2007.19.4.587} } @ARTICLE{Piazza2007, author = {Manuela Piazza and Philippe Pinel and Denis Le Bihan and Stanislas Dehaene}, title = {A Magnitude Code Common to Numerosities and Number Symbols in Human Intraparietal Cortex.}, journal = {Neuron}, year = {2007}, volume = {53}, pages = {293--305}, number = {2}, month = {Jan}, abstract = {Activation of the horizontal segment of the intraparietal sulcus (hIPS) has been observed in various number-processing tasks, whether numbers were conveyed by symbolic numerals (digits, number words) or by nonsymbolic displays (dot patterns). This suggests an abstract coding of numerical magnitude. Here, we critically tested this hypothesis using fMRI adaptation to demonstrate notation-independent coding of numerical quantity in the hIPS. Once subjects were adapted either to dot patterns or to Arabic digits, activation in the hIPS and in frontal regions recovered in a distance-dependent fashion whenever a new number was presented, irrespective of notation changes. This remained unchanged when analyzing the hIPS peaks from an independent localizer scan of mental calculation. These results suggest an abstract coding of approximate number common to dots, digits, and number words. They support the idea that symbols acquire meaning by linking neural populations coding symbol shapes to those holding nonsymbolic representations of quantities.}, doi = {10.1016/j.neuron.2006.11.022}, pdf = {http://www.unicog.org/publications/PiazzaDehaene_AbstractNumericalAdaptation_neuron2006.pdf}, owner = {chrplr}, pii = {S0896-6273(06)00989-5}, pmid = {17224409}, timestamp = {2007.01.23}, url = {http://dx.doi.org/10.1016/j.neuron.2006.11.022} } @ARTICLE{Reuter2007, author = {Françoise Reuter and Del Cul, Antoine and Bertrand Audoin and Irina Malikova and Lionel Naccache and Jean Philippe Ranjeva and Olivier Lyon-Caen and André Ali Chérif and Laurent Cohen and Stanislas Dehaene and Jean Pelletier}, title = {Intact subliminal processing and delayed conscious access in multiple sclerosis.}, journal = {Neuropsychologia}, year = {2007}, month = {Apr}, abstract = {Periventricular white matter damage affecting large bundles connecting distant cortical areas may constitute the main neuronal mechanism for the deficit of controlled information processing observed in patients with early multiple sclerosis (MS). Visual backward masking has been demonstrated to affect late stages of conscious perception involving long-range interactions between visual perceptual areas and higher level integrative cortices while leaving intact early feed-forward visual processing and even complex processing such as object recognition or semantic processing. We therefore hypothesized that patients with early MS would have an elevated masking threshold, because of an impairment of conscious perception whereas subliminal processing of masked stimuli would be preserved. Twenty-two patients with early MS and 22 normal controls performed two backward-masking experiments. We used Arabic digits as stimuli and varied quasi-continuously the temporal interval with a subsequent mask, thus allowing us to progressively "unmask" the stimuli. We finely quantified the visibility of the masked stimuli using both objective and subjective measures, thus obtaining accurate estimates of the threshold duration for access to consciousness. We also studied the priming effect caused by the variably masked numbers on a comparison task performed on a subsequently presented and highly visible target number. The threshold for access to consciousness of masked stimuli was elevated in MS patients compared to controls, whereas non-conscious processing of these stimuli, as measured by priming, was preserved. These findings suggest that conscious access to masked stimuli depends on the integrity of large-scale cortical integrative processes, which involve long-distance white matter projections, and are impaired due to diffuse demyelinating injury in patients with early MS.}, doi = {10.1016/j.neuropsychologia.2007.04.010}, pdf = {http://www.unicog.org/publications/Reuter_MultipleSclerosisPriming_Neuropsychologia2007.pdf}, owner = {chrplr}, pii = {S0028-3932(07)00149-2}, pmid = {17517425}, timestamp = {2007.06.27}, url = {http://dx.doi.org/10.1016/j.neuropsychologia.2007.04.010} } @ARTICLE{Rodrigo2007, author = {S. Rodrigo and Catherine Oppenheim and F. Chassoux and Narly Golestani and Yann Cointepas and Cyrille Poupon and Franck Semah and Jean-Fran{\c{c}}ois Mangin and Denis Le Bihan and J-F. Meder}, title = {Uncinate fasciculus fiber tracking in mesial temporal lobe epilepsy. Initial findings.}, journal = {Eur Radiol}, year = {2007}, month = {Jan}, abstract = {In temporal lobe epilepsy (TLE) due to hippocampal sclerosis (HS), ictal discharge spread to the frontal and insulo-perisylvian cortex is commonly observed. The implication of white matter pathways in this propagation has not been investigated. We compared diffusion tensor imaging (DTI) measurements along the uncinate fasciculus (UF), a major tract connecting the frontal and temporal lobes, in patients and controls. Ten right-handed patients referred for intractable TLE due to a right HS were investigated on a 1.5-T MR scanner including a DTI sequence. All patients had interictal fluorodeoxyglucose PET showing an ipsilateral temporal hypometabolism associated with insular and frontal or perisylvian hypometabolism. The controls consisted of ten right-handed healthy subjects. UF fiber tracking was performed, and its fractional anisotropy (FA) values were compared between patients and controls, separately for the right and left UF. The left-minus-right FA UF asymmetry index was computed to test for intergroup differences. Asymmetries were found in the control group with right-greater-than-left FA. This asymmetrical pattern was lost in the patient group. Right FA values were lower in patients with right HS versus controls. Although preliminary, these findings may be related to the preferential pathway of seizure spread from the mesial temporal lobe to frontal and insulo-perisylvian areas.}, doi = {10.1007/s00330-006-0558-x}, owner = {chrplr}, pmid = {17219141}, timestamp = {2007.03.22}, url = {http://dx.doi.org/10.1007/s00330-006-0558-x} } @ARTICLE{Sigman2007, author = {M. Sigman and A. Jobert and D. Lebihan and S. Dehaene}, title = {Parsing a sequence of brain activations at psychological times using fMRI.}, journal = {Neuroimage}, year = {2007}, volume = {35}, pages = {655--668}, number = {2}, month = {Apr}, abstract = {Identifying the sequence of computations which constitute a cognitive task is a fundamental problem in neuroscience. Here we show, using functional magnetic resonance imaging (fMRI), that we can parse, at the time scale of about 100 ms, the different stages of brain activations which compose a complex sequential task. To identify timing information from the slow blood oxygen level-dependent (BOLD) signal response, we use a simple analytic method, based on periodic stimulation and an analysis of covariation of the spectral parameters (phase and power spectrum at the stimulation frequency) with the different experimental conditions. We implement this strategy in a sequential task, where the onset and duration of different stages are under experimental control. We are able to detect changes in onset latency and in the duration of the response, in an invariant fashion across different brain regions, and reconstruct the stream of activations consistent with five distinct stages of processing of the task. Sensory and motor clusters activate in the expected order and for the expected duration. The timing of sensory activations is more precise than the timing of motor activation. We also parse in time the reading-verbal network: visual extrastriate and phonological access regions (supramarginal gyrus) activate at the time of word presentation, while the inferior frontal gyrus, the anterior cingulate and the supplementary motor area are activated during the rehearsal period.}, doi = {10.1016/j.neuroimage.2006.05.064}, pdf = {http://www.unicog.org/publications/SigmanDehaene_TemporalParsingInfMRI_Neuroimage2007.pdf}, keywords = {Adult; Brain; Cognition; Humans; Magnetic Resonance Imaging; Task Performance and Analysis; Time Factors}, owner = {chrplr}, pii = {S1053-8119(06)00646-X}, pmid = {17275341}, timestamp = {2007.06.27}, url = {http://dx.doi.org/10.1016/j.neuroimage.2006.05.064} } @ARTICLE{Sterzer2007, author = {Philipp Sterzer and Andreas Kleinschmidt}, title = {A neural basis for inference in perceptual ambiguity.}, journal = {Proc Natl Acad Sci U S A}, year = {2007}, volume = {104}, pages = {323--328}, number = {1}, month = {Jan}, abstract = {When looking at ambiguous visual stimuli, the observer experiences frequent spontaneous transitions between two competing percepts while physical stimulation remains unchanged. Despite recent advances in understanding the neural processes underlying such perceptual rivalry, a key question has remained unresolved: Does perceptual rivalry result merely from local bistability of neural activity patterns in sensory stimulus representations, or do higher-order areas play a causal role by shifting inference and, thus, initiating perceptual changes? We used functional MRI to measure brain activity while human observers reported successive spontaneous changes in perceived direction for an ambiguous apparent motion stimulus. In a control condition, the individual sequences of spontaneous perceptual switches during bistability were replayed by using a disambiguated version of the stimulus. Greater activations during spontaneous compared with stimulus-driven switches were observed in inferior frontal cortex bilaterally. Subsequent chronometric analyses of event-related signal time courses showed that, relative to activations in motion-sensitive extrastriate visual cortex, right inferior frontal cortex activation occurred earlier during spontaneous than during stimulus-driven perceptual changes. The temporal precedence of right inferior frontal activations suggests that this region participates in initiating spontaneous switches in perception during constant physical stimulation. Our findings can thus be seen as a signature of when and where the brain "makes up its mind" about competing perceptual interpretations of a given sensory input pattern.}, doi = {10.1073/pnas.0609006104}, pdf = {http://www.unicog.org/publications/sterzer_kleinschmidt_pnas_2006.pdf}, owner = {chrplr}, pii = {0609006104}, pmid = {17190824}, timestamp = {2007.02.06}, url = {http://dx.doi.org/10.1073/pnas.0609006104} } @ARTICLE{Sterzer2007a, author = {Philipp Sterzer and Christina Stadler and Fritz Poustka and Andreas Kleinschmidt}, title = {A structural neural deficit in adolescents with conduct disorder and its association with lack of empathy.}, journal = {Neuroimage}, year = {2007}, volume = {37}, pages = {335--342}, number = {1}, month = {Aug}, abstract = {The goal of this study was to determine whether brain regions implicated in emotion processing show structural alterations in adolescents with conduct disorder (CD). Using an optimized voxel-based morphometry protocol, we compared grey matter volume in 12 patients with CD and 12 age-, sex-, and intelligence-matched control subjects. Grey matter volume in bilateral anterior insular cortex and the left amygdala was significantly reduced in CD patients compared to healthy control subjects. The insular grey matter abnormalities could be attributed to aggressive behaviour. Moreover, bilateral anterior insular grey matter volume in CD patients correlated significantly with empathy scores. These novel findings point at a joint neuroanatomical substrate underpinning aggressive behaviour and impaired capacity of empathy and suggest a critical role for the anterior insula in regulating social behaviour.}, doi = {10.1016/j.neuroimage.2007.04.043}, pdf = {http://www.unicog.org/publications/Sterzer_ni_aggress_2007.pdf}, institution = {Department of Neurology, Johann Wolfgang Goethe University, Frankfurt am Main, Germany. philipp.sterzer@charite.de}, keywords = {Adolescent; Aggression; Amygdala; Attention Deficit Disorder with Hyperactivity; Cerebral Cortex; Conduct Disorder; Dominance, Cerebral; Emotions; Empathy; Frontal Lobe; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Personality Assessment; Reference Values; Social Behavior; Statistics as Topic}, owner = {chrplr}, pii = {S1053-8119(07)00321-7}, pmid = {17553706}, timestamp = {2008.04.10}, url = {http://dx.doi.org/10.1016/j.neuroimage.2007.04.043} } @ARTICLE{Thirion2007, author = {Bertrand Thirion and Philippe Pinel and Sébastien Mériaux and Alexis Roche and Stanislas Dehaene and Jean-Baptiste Poline}, title = {Analysis of a large fMRI cohort: Statistical and methodological issues for group analyses.}, journal = {Neuroimage}, year = {2007}, volume = {35}, pages = {105--120}, number = {1}, month = {Mar}, abstract = {The aim of group fMRI studies is to relate contrasts of tasks or stimuli to regional brain activity increases. These studies typically involve 10 to 16 subjects. The average regional activity statistical significance is assessed using the subject to subject variability of the effect (random effects analyses). Because of the relatively small number of subjects included, the sensitivity and reliability of these analyses is questionable and hard to investigate. In this work, we use a very large number of subject (more than 80) to investigate this issue. We take advantage of this large cohort to study the statistical properties of the inter-subject activity and focus on the notion of reproducibility by bootstrapping. We asked simple but important methodological questions: Is there, from the point of view of reliability, an optimal statistical threshold for activity maps? How many subjects should be included in group studies? What method should be preferred for inference? Our results suggest that i) optimal thresholds can indeed be found, and are rather lower than usual corrected for multiple comparison thresholds, ii) 20 subjects or more should be included in functional neuroimaging studies in order to have sufficient reliability, iii) non-parametric significance assessment should be preferred to parametric methods, iv) cluster-level thresholding is more reliable than voxel-based thresholding, and v) mixed effects tests are much more reliable than random effects tests. Moreover, our study shows that inter-subject variability plays a prominent role in the relatively low sensitivity and reliability of group studies.}, doi = {10.1016/j.neuroimage.2006.11.054}, pdf = {http://www.unicog.org/publications/ThirionPinelDehaenePoline_LargefMRIcohortGroupAnalyses_Neuroimage2007.pdf}, keywords = {Algorithms; Brain Mapping; Cluster Analysis; Cohort Studies; Databases, Factual; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Models, Neurological; Models, Statistical; Reproducibility of Results; Sample Size}, owner = {chrplr}, pii = {S1053-8119(06)01168-2}, pmid = {17239619}, timestamp = {2007.06.05}, url = {http://dx.doi.org/10.1016/j.neuroimage.2006.11.054} } @ARTICLE{Vinckier2007, author = {Fabien Vinckier and Stanislas Dehaene and Antoinette Jobert and Jean Philippe Dubus and Mariano Sigman and Laurent Cohen}, title = {Hierarchical coding of letter strings in the ventral stream: dissecting the inner organization of the visual word-form system.}, journal = {Neuron}, year = {2007}, volume = {55}, pages = {143--156}, number = {1}, month = {Jul}, abstract = {Visual word recognition has been proposed to rely on a hierarchy of increasingly complex neuronal detectors, from individual letters to bigrams and morphemes. We used fMRI to test whether such a hierarchy is present in the left occipitotemporal cortex, at the site of the visual word-form area, and with an anterior-to-posterior progression. We exposed adult readers to (1) false-font strings; (2) strings of infrequent letters; (3) strings of frequent letters but rare bigrams; (4) strings with frequent bigrams but rare quadrigrams; (5) strings with frequent quadrigrams; (6) real words. A gradient of selectivity was observed through the entire span of the occipitotemporal cortex, with activation becoming more selective for higher-level stimuli toward the anterior fusiform region. A similar gradient was also seen in left inferior frontoinsular cortex. Those gradients were asymmetrical in favor of the left hemisphere. We conclude that the left occipitotemporal visual word-form area, far from being a homogeneous structure, presents a high degree of functional and spatial hierarchical organization which must result from a tuning process during reading acquisition.}, doi = {10.1016/j.neuron.2007.05.031}, pdf = {http://www.unicog.org/publications/VinckierCohenDehaene_VisualWordFormHierarchy_Neuron2007.pdf}, owner = {chrplr}, pii = {S0896-6273(07)00450-3}, pmid = {17610823}, timestamp = {2007.07.07}, url = {http://dx.doi.org/10.1016/j.neuron.2007.05.031} } @PHDTHESIS{Izard2006, author = {Véronique Izard}, title = {Interactions entre les représentations numériques verbales et non-verbales: étude théorique et expérimentale}, school = {Université Paris 6}, year = {2006}, type = {Thesis/Dissertation}, note = {supervised by Stanislas Dehaene}, abstract = {L'homme manipule les nombres en utilisant les mots de sa langue. De plus, tout un ensemble de données convergent pour indiquer qu'il dispose aussi d'un système non-verbal pour représenter la numérosité des ensembles, système hérité du monde animal. Nous avons abordé la question des interactions entre représentations numériques verbales et non-verbales, en étudiant trois populations différentes : des adultes occidentaux, des bébés de trois mois, ainsi que des Indiens d'Amazonie, les Mundu! rucus, peuple dont la langue possède un lexique numérique très restreint. Nos recherches s'articulent autour des trois axes suivants : 1. Tout d'abord nous avons cherché à donner une caractérisation fine des représentations non-verbales de la numérosité, à l'aide d'un modèle mathématique, qui postule que les numérosités sont représentées sur un continuum interne, la ligne numérique interne. Les prédictions! du modèle s'accordent avec un ensemble de mesures expérimentales, sur des tâches de comparaison, d'addition et de soustraction de numérosités. Enfin, en confrontant les prédictions du modèle aux résultats d'une tâche d'estimation de numérosité que nous avons développée, nous avons pu conclure que la ligne numérique interne est compressive. 2. Par ailleurs, nos travaux sur l'estimation abordent la question des liens entre les représentations de numérosités et les numéraux de la langue. De manière spontanée, les sujets ont une tendance marquée à sous-estimer la numérosité des stimuli, mais la donnée d'un indice suffit à modifier radicalement la manière dont ils sont calibrés. De plus, le processus de calibration agit de manière globale sur toute la ligne numérique. 3. Enfin, que se passe-t-il en l'absence de représentations verbales pour les nombres ? A l'aide de la technique des potentiels évoqués (ERPs), nous avons montré que les bébés âgés de trois mois sont déjà sensibles à la numérosité. Par ailleurs, nos expériences chez les Indiens Mundurucus montrent qu'en l'absence d'un lexique pour les grands nombres, ceux-ci déploient les mêmes compétences que des occidentaux dans des tâches d'arithmétique sur la numérosité, tant qu'on n'exige qu'une réponse approximative. De plus, les Mundurucus possèdent un concept d'égalité exacte, transcendant leurs représentations non-verbales approximatives de numérosité, mais se trouvent limités dans la plupart des tâches d'arithmétique exacte, de fait qu'il leur manque un outil cognitif (analogue à notre procédure de comptage) pour évaluer! la numérosité exacte d'un ensemble. Ces résultats nous éclairent sur les influences respectives de notre bagage biologique et de la culture dans le développement de la cognition numérique.}, pdf = {http://www.unicog.org/publications/Izard_thesis_2006.pdf}, owner = {chrplr}, timestamp = {2006.04.25} } @INCOLLECTION{pallier06_neurophysio, author = {Christophe Pallier}, title = {Imagerie cérébrale du cerveau bilingue}, booktitle = {Neurophysiologie du langage}, publisher = {Elsevier}, year = {2006}, editor = {Catherine Liégeois-Chauvel and Bernard Guéguen and Patrick Chauvel and Philippe Kahane}, owner = {chrplr}, timestamp = {2007.03.02} } @ARTICLE{Alario2006, author = {F-Xavier Alario and Hanna Chainay and Stéphane Lehericy and Laurent Cohen}, title = {The role of the supplementary motor area {SMA} in word production.}, journal = {Brain Res}, year = {2006}, volume = {1076}, pages = {129--143}, number = {1}, month = {Mar}, abstract = {The supplementary motor area (SMA) is a key structure for behavioral planning and execution. Recent research on motor control conducted with monkeys and humans has put to light an anatomical and functional distinction between pre-SMA and SMA-proper. According to this view, the pre-SMA would be involved in higher level processes while the SMA-proper would be more closely tied to motor output. We extended this general framework to the verbal domain, in order to investigate the role of the SMA in speech production. We conducted two speech production experiments with fMRI where we manipulated parameters such as familiarity, complexity or constraints on word selection. The results reveal a parcellation of the SMA into three distinct regions, according to their involvement in different aspects of word production. More specifically, following a rostrocaudal gradient, we observed differential activations related to lexical selection, linear sequence encoding and control of motor output. A parallel organization was observed in the dorsolateral frontal cortex. By refining its anatomical and functional parcellation, these results clarify the roles of the SMA in speech production.}, doi = {10.1016/j.brainres.2005.11.104}, pdf = {http://www.unicog.org/publications/alario_SMA_BRES_2006.pdf}, keywords = {Adult; Brain Mapping; Choice Behavior; Female; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Motor Cortex; Oxygen; Photic Stimulation; Reading; Time Factors; Verbal Behavior}, owner = {chrplr}, pii = {S0006-8993(05)01653-7}, pmid = {16480694}, timestamp = {2007.01.24}, url = {http://dx.doi.org/10.1016/j.brainres.2005.11.104} } @ARTICLE{Andoh2006, author = {Jamila Andoh and Eric Artiges and Christophe Pallier and Denis Rivière and Jean-François Mangin and Arnaud Cachia and Marion Plaze and Maris-Laure Paillère-Martinot and Jean-Luc Martinot}, title = {Modulation of language areas with functional {MR} image-guided magnetic stimulation.}, journal = {Neuroimage}, year = {2006}, volume = {29}, pages = {619--627}, number = {2}, month = {Jan}, abstract = {Repetitive transcranial magnetic stimulation (rTMS) can interfere with linguistic performance when delivered over language areas. At low frequency (1 Hz), rTMS is assumed to decrease cortical excitability; however, the degree of TMS effect on cortical language areas may depend on the localization of the stimulation coil with respect to the inter-individual anatomo-functional variations. Hence, we aimed at investigating individual brain areas involved in semantic and phonological auditory processes. We hypothesized that active rTMS targeted over Wernicke's area might modify the performance during a language-fragment-detection task. Sentences in native or foreign languages were presented to 12 right-handed male healthy volunteers during functional magnetic resonance imaging (fMRI). 3D-functional maps localized the posterior temporal activation (Wernicke) in each subject and MRI anatomical cortical landmarks were used to define Broca's pars opercularis (F3Op). A frameless stereotaxy system was used to guide the TMS coil position over Wernicke's and F3Op areas in each subject. Active and placebo randomized rTMS sessions were applied at 1 Hz, 110\% of motor threshold, during the same language-fragment-detection task. Accuracy and response time (RT) were recorded. RT was significantly decreased by active rTMS compared to placebo over Wernicke's area, and was more decreased for native than for foreign languages. No significant RT change was observed for F3Op area. rTMS conditions did not impair participants' accuracy. Thus, low-frequency rTMS over Wernicke's area can speed-up the response to a task tapping on native language perception in healthy volunteers. This individually-guided stimulation study confirms that facilitatory effects are not confined to high-frequency rTMS.}, doi = {10.1016/j.neuroimage.2005.07.029}, pdf = {http://www.pallier.org/papers/Andoh.tms.Neuroimage.2006}, owner = {chrplr}, pii = {S1053-8119(05)00550-1}, pmid = {16168674}, timestamp = {2006.02.02}, url = {http://dx.doi.org/10.1016/j.neuroimage.2005.07.029} } @ARTICLE{Artiges2006, author = {Eric Artiges and Catherine Martelli and Lionel Naccache and David Bartrés-Faz and Jean-Bernard Leprovost and Armelle Viard and Marie-Laure Paillère-Martinot and Stanislas Dehaene and Jean-Luc Martinot}, title = {{P}aracingulate sulcus morphology and f{MRI} activation detection in schizophrenia patients.}, journal = {Schizophr Res}, year = {2006}, volume = {82}, pages = {143--151}, number = {2-3}, month = {Feb}, abstract = {OBJECTIVE: Altered anterior cingulate cortex activity has been consistently detected by functional imaging in schizophrenia patients. In the present study, we hypothesized that the detection of such local hypoactivity varies when the subjects' local gyrification is monitored. Using a group-statistical approach, we investigated whether the presence or absence of a paracingulate sulcus (PCS) does influence the detection of the activation patterns in the cognitive division of the anterior cingulate cortex (ACcd). METHOD: fMRI data were acquired using an event-related paradigm during a task involving both priming and interference between stimuli. In the fMRI dataset collected from 13 schizophrenia patients and 16 healthy subjects, subgroups were defined according to the presence or absence of a PCS. Regional activations during interference between stimuli were examined in the ACcd of each hemisphere, using for each region of interest both voxel-based random-effects and non-parametric analyses. RESULTS: ACcd activation was left-sided in healthy subjects with a PCS, and right-sided in healthy subjects devoid of a PCS. ACcd activations were detected bilaterally in schizophrenia patients with a PCS, whereas left ACcd was deactivated in patients without a PCS. Subgroup comparisons revealed no difference between healthy subjects with a PCS and patients with a PCS, whereas in the subgroups devoid of PCS, the patients exhibited a bilateral ACcd hypoactivation relative to healthy subjects. CONCLUSIONS: PCS presence or absence influences the detection of ACcd activations in group-analysis of schizophrenia patients.}, doi = {10.1016/j.schres.2005.10.022}, pdf = {http://www.unicog.org/publications/Artiges_SchizoPCS_SchizoResearch2005.pdf}, keywords = {16387476}, owner = {dehaene}, pii = {S0920-9964(05)00480-9}, pmid = {16387476}, timestamp = {2006.03.02}, url = {http://dx.doi.org/10.1016/j.schres.2005.10.022} } @ARTICLE{Baier2006, author = {Bernhard Baier and Andreas Kleinschmidt and Notger G Müller}, title = {Cross-modal processing in early visual and auditory cortices depends on expected statistical relationship of multisensory information.}, journal = {J Neurosci}, year = {2006}, volume = {26}, pages = {12260--12265}, number = {47}, month = {Nov}, note = {IMPORTANT Correction: In Figure 2B of the article, the colors for the associated and non-associated conditions were switched by mistake.}, abstract = {Previous studies have shown that processing information in one sensory modality can either be enhanced or attenuated by concurrent stimulation of another modality. Here, we reconcile these apparently contradictory results by showing that the sign of cross-modal interactions depends on whether the content of two modalities is associated or not. When concurrently presented auditory and visual stimuli are paired by chance, cue-induced preparatory neural activity is strongly enhanced in the task-relevant sensory system and suppressed in the irrelevant system. Conversely, when information in the two modalities is reliably associated, activity is enhanced in both systems regardless of which modality is task relevant. Our findings illustrate an ecologically optimal flexibility of the neural mechanisms that govern multisensory processing: facilitation occurs when integration is expected, and suppression occurs when distraction is expected. Because thalamic structures were more active when the senses needed to operate separately, we propose them to serve gatekeeper functions in early cross-modal interactions.}, doi = {10.1523/JNEUROSCI.1457-06.2006}, pdf = {http://www.unicog.org/publications/baier_jneurosci.pdf}, keywords = {Acoustic Stimulation; Adult; Afferent Pathways; Auditory Cortex; Brain Mapping; Cues; Female; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Oxygen; Photic Stimulation; Reaction Time; Thalamus; Visual Cortex}, owner = {chrplr}, pii = {26/47/12260}, pmid = {17122051}, timestamp = {2007.02.06}, url = {http://dx.doi.org/10.1523/JNEUROSCI.1457-06.2006} } @ARTICLE{Birdsong2006, author = {David Birdsong}, title = {Age and Second Language Acquisition and Processing: A Selective Overview}, journal = {Language Learning}, year = {2006}, volume = {56}, pages = {9--49}, abstract = {This article provides a selective overview of theoretical issues and empirical findings relating to the question of age and second language acquisition (L2A). Both behavioral and brain-based data are discussed in the contexts of neurocognitive aging and cognitive neurofunction in the mature individual. Moving beyond the classical notion of "deficient" L2 processing and acquisition, we consider the complementary question of learner potential in postadolescent L2A.}, pdf = {Birdsong.critical.period.selective.overview.language.learning.2006.pdf}, owner = {chrplr}, timestamp = {2007.02.12} } @ARTICLE{Dehaene2006a, author = {Stanislas Dehaene and Jean-Pierre Changeux and Lionel Naccache and Jérôme Sackur and Claire Sergent}, title = {{C}onscious, preconscious, and subliminal processing: a testable taxonomy.}, journal = {Trends Cogn Sci}, year = {2006}, month = {Apr}, abstract = {Of the many brain events evoked by a visual stimulus, which are specifically associated with conscious perception, and which merely reflect non-conscious processing? Several recent neuroimaging studies have contrasted conscious and non-conscious visual processing, but their results appear inconsistent. Some support a correlation of conscious perception with early occipital events, others with late parieto-frontal activity. Here we attempt to make sense of these dissenting results. On the basis of the global neuronal workspace hypothesis, we propose a taxonomy that distinguishes between vigilance and access to conscious report, as well as between subliminal, preconscious and conscious processing. We suggest that these distinctions map onto different neural mechanisms, and that conscious perception is systematically associated with surges of parieto-frontal activity causing top-down amplification.}, doi = {10.1016/j.tics.2006.03.007}, pdf = {http://www.unicog.org/publications/DehaeneChangeuxNaccacheSackurSergent_TaxonomyPreconscious_TICS2006.pdf}, keywords = {16603406}, owner = {dehaene}, pii = {S1364-6613(06)00079-9}, pmid = {16603406}, timestamp = {2006.05.10}, url = {http://dx.doi.org/10.1016/j.tics.2006.03.007} } @ARTICLE{Dehaene2006, author = {Stanislas Dehaene and Véronique Izard and Pierre Pica and Elizabeth Spelke}, title = {{C}ore knowledge of geometry in an {A}mazonian indigene group.}, journal = {Science}, year = {2006}, volume = {311}, pages = {381--384}, number = {5759}, month = {Jan}, abstract = {Does geometry constitute a core set of intuitions present in all humans, regardless of their language or schooling? We used two nonverbal tests to probe the conceptual primitives of geometry in the Mundurukú, an isolated Amazonian indigene group. Mundurukú children and adults spontaneously made use of basic geometric concepts such as points, lines, parallelism, or right angles to detect intruders in simple pictures, and they used distance, angle, and sense relationships in geometrical maps to locate hidden objects. Our results provide evidence for geometrical intuitions in the absence of schooling, experience with graphic symbols or maps, or a rich language of geometrical terms.}, doi = {10.1126/science.1121739}, pdf = {http://www.unicog.org/publications/DehaeneIzardPicaSpelke_CoreKnowledgeGeometryMunduruku_Science2006.pdf}, keywords = {80 and over, Adolescent, Adult, Aged, Analysis of Variance, Brazil, Child, Comprehension, Culture, Extramural, Female, Humans, Indians, Knowledge, Language, Male, Maps, Mathematics, Middle Aged, N.I.H., Non-U.S. Gov't, Preschool, Research Support, South American, 16424304}, owner = {dehaene}, pii = {311/5759/381}, pmid = {16424304}, timestamp = {2006.03.02}, url = {http://dx.doi.org/10.1126/science.1121739} } @ARTICLE{Dehaene2006b, author = {Stanislas Dehaene and Lionel Naccache}, title = {Can one suppress subliminal words?}, journal = {Neuron}, year = {2006}, volume = {52}, pages = {397--399}, number = {3}, month = {Nov}, abstract = {Subliminal words cause behavioral priming, yet the depth of their processing remains debated. Using transcranial magnetic stimulation (TMS), Nakamura et al. demonstrate in this issue of Neuron that this subliminal priming effect can be selectively disrupted. Distinct TMS sites disrupt priming in lexical decision and pronunciation tasks, suggesting that task set influences subliminal processing.}, doi = {10.1016/j.neuron.2006.10.018}, keywords = {Brain; Brain Mapping; Discrimination (Psychology); Humans; Linguistics; Reaction Time; Subliminal Stimulation; Transcranial Magnetic Stimulation}, owner = {chrplr}, pii = {S0896-6273(06)00817-8}, pmid = {17088205}, timestamp = {2007.01.23}, url = {http://dx.doi.org/10.1016/j.neuron.2006.10.018} } @ARTICLE{Lambertz2006, author = {Dehaene-Lambertz, Ghislaine and Stanislas Dehaene and Jean-Luc Anton and Aurelie Campagne and Philippe Ciuciu and Guillaume P Dehaene and Isabelle Denghien and Antoinette Jobert and Denis Lebihan and Mariano Sigman and Christophe Pallier and Jean-Baptiste Poline}, title = {{F}unctional segregation of cortical language areas by sentence repetition}, journal = {Hum Brain Mapp}, year = {2006}, volume = {27}, pages = {360--371}, number = {5}, month = {May}, abstract = {The functional organization of the perisylvian language network was examined using a functional MRI (fMRI) adaptation paradigm with spoken sentences. In Experiment 1, a given sentence was presented every 14.4 s and repeated two, three, or four times in a row. The study of the temporal properties of the BOLD response revealed a temporal gradient along the dorsal-ventral and rostral-caudal directions: From Heschl's gyrus, where the fastest responses were recorded, responses became increasingly slower toward the posterior part of the superior temporal gyrus and toward the temporal poles and the left inferior frontal gyrus, where the slowest responses were observed. Repetition induced a decrease in amplitude and a speeding up of the BOLD response in the superior temporal sulcus (STS), while the most superior temporal regions were not affected. In Experiment 2, small blocks of six sentences were presented in which either the speaker voice or the linguistic content of the sentence, or both, were repeated. Data analyses revealed a clear asymmetry: While two clusters in the left superior temporal sulcus showed identical repetition suppression whether the sentences were produced by the same speaker or different speakers, the homologous right regions were sensitive to sentence repetition only when the speaker voice remained constant. Thus, hemispheric left regions encode linguistic content while homologous right regions encode more details about extralinguistic features like speaker voice. The results demonstrate the feasibility of using sentence-level adaptation to probe the functional organization of cortical language areas. Hum Brain Mapp, 2006. (c) 2006 Wiley-Liss, Inc.}, doi = {10.1002/hbm.20250}, pdf = {http://www.unicog.org/publications/Dehaene-Lambertz&al_FIAC_HBM2006.pdf}, owner = {dehaene}, pmid = {16565949}, timestamp = {2006.05.10}, url = {http://dx.doi.org/10.1002/hbm.20250} } @ARTICLE{Dehaene-Lambertz2006a, author = {Dehaene-Lambertz, G. and Hertz-Pannier, L. and Dubois, J. and Mériaux, S. and Roche, A. and Sigman, M. and Dehaene, S.}, title = {Functional organization of perisylvian activation during presentation of sentences in preverbal infants}, journal = pnas, year = {2006}, volume = {103}, pages = {14240-14245}, pdf = {http://www.unicog.org/publications/DehaeneLambertz_HertzPannier_al_Phrases_PNAS2006.pdf}, owner = {chrplr}, timestamp = {2007.02.13} } @ARTICLE{Dehaene-Lambertz2006, author = {Dehaene-Lambertz, G. and Hertz-Pannier, L. and Dubois, J.}, title = {Nature and nurture in language acquisition: Anatomical and functional brain-imaging studies in infants}, journal = {Trends in Neuroscience}, year = {2006}, volume = {29}, pages = {367--373}, number = {7}, pdf = {http://www.unicog.org/publications/DelaeneLambertz-HertzPannier-Dubois_NatureNurture_TINS2006.pdf}, owner = {chrplr}, timestamp = {2007.02.13} } @ARTICLE{DelCul2006, author = {Del Cul, Antoine and Stanislas Dehaene and Marion Leboyer}, title = {Preserved subliminal processing and impaired conscious access in schizophrenia.}, journal = {Arch Gen Psychiatry}, year = {2006}, volume = {63}, pages = {1313--1323}, number = {12}, month = {Dec}, abstract = {BACKGROUND: Studies of visual backward masking have frequently revealed an elevated masking threshold in schizophrenia. This finding has frequently been interpreted as indicating a low-level visual deficit. However, more recent models suggest that masking may also involve late and higher-level integrative processes, while leaving intact early bottom-up visual processing. OBJECTIVE: To test the hypothesis that the backward-masking deficit in schizophrenia corresponds to a deficit in the late stages of conscious perception, whereas the subliminal processing of masked stimuli is fully preserved. DESIGN: Twenty-eight patients with schizophrenia and 28 normal control subjects performed 2 backward-masking experiments. We used Arabic digits as stimuli and varied quasi-continuously the interval with a subsequent mask, thus allowing us to progressively unmask the stimuli. We finely quantified their degree of visibility using objective and subjective measures to evaluate the threshold duration for access to consciousness. We also studied the priming effect caused by the variably masked numbers in a comparison task performed on a subsequently presented and highly visible target number. RESULTS: The threshold delay between the digit and mask necessary for the conscious perception of the masked stimulus was longer in patients compared with controls. This higher consciousness threshold in patients was confirmed by an objective and a subjective measure, and both measures were highly correlated for the patients and controls. However, subliminal priming of masked numbers was effective and identical in patients and controls. CONCLUSIONS: Access to conscious report of masked stimuli is impaired in schizophrenia, whereas fast bottom-up processing of the same stimuli, as assessed by subliminal priming, is preserved. These findings suggest a high-level origin of the masking deficit in schizophrenia, although they leave open for further research its exact relation to previously identified bottom-up visual processing abnormalities.}, doi = {10.1001/archpsyc.63.12.1313}, pdf = {http://www.unicog.org/publications/DelculDehaeneLeboyer_ImpairedConsciousAccessSchizophrenia_AGP2006.pdf}, keywords = {Adolescent; Adult; Comorbidity; Consciousness Disorders; Female; Form Perception; Humans; Male; Middle Aged; Neuropsychological Tests; Perceptual Masking; Psychomotor Performance; Schizophrenia; Schizophrenic Psychology; Sensory Thresholds; Subliminal Stimulation}, owner = {chrplr}, pii = {63/12/1313}, pmid = {17146006}, timestamp = {2007.01.23}, url = {http://dx.doi.org/10.1001/archpsyc.63.12.1313} } @ARTICLE{JDubois2006, author = {J. Dubois and L. Hertz-Pannier and G. Dehaene-Lambertz and Y. Cointepas and D. Le Bihan}, title = {{A}ssessment of the early organization and maturation of infants' cerebral white matter fiber bundles: a feasibility study using quantitative diffusion tensor imaging and tractography.}, journal = {Neuroimage}, year = {2006}, volume = {30}, pages = {1121--1132}, number = {4}, month = {May}, abstract = {The human infant is particularly immature at birth and brain maturation, with the myelination of white matter fibers, is protracted until adulthood. Diffusion tensor imaging offers the possibility to describe non invasively the fascicles spatial organization at an early stage and to follow the cerebral maturation with quantitative parameters that might be correlated with behavioral development. Here, we assessed the feasibility to study the organization and maturation of major white matter bundles in eighteen 1- to 4-month-old healthy infants, using a specific acquisition protocol customized to the immature brain (with 15 orientations of the diffusion gradients and a 700 s mm(-2)b factor). We were able to track most of the main fascicles described at later ages despite the low anisotropy of the infant white matter, using the FACT algorithm. This mapping allows us to propose a new method of quantification based on reconstructed tracts, split between specific regions, which should be more sensitive to specific changes in a bundle than the conventional approach, based on regions-of-interest. We observed variations in fractional anisotropy and mean diffusivity over the considered developmental period in most bundles (corpus callosum, cerebellar peduncles, cortico-spinal tract, spino-thalamic tract, capsules, radiations, longitudinal and uncinate fascicles, cingulum). The results are in good agreement with the known stages of white matter maturation and myelination, and the proposed approach might provide important insights on brain development.}, doi = {10.1016/j.neuroimage.2005.11.022}, pdf = {http://www.unicog.org/publications/DuboisHertzPannierDehaene-Lambertz_TrackingBB_NeuroImg2OO6.pdf}, keywords = {16413790}, owner = {gdehaene}, pii = {S1053-8119(05)02453-5}, pmid = {16413790}, timestamp = {2006.06.27}, url = {http://dx.doi.org/10.1016/j.neuroimage.2005.11.022} } @ARTICLE{Gaillard2006a, author = {Raphaël Gaillard and Del Cul, Antoine and Lionel Naccache and Fabien Vinckier and Laurent Cohen and Stanislas Dehaene}, title = {{N}onconscious semantic processing of emotional words modulates conscious access.}, journal = {Proc Natl Acad Sci U S A}, year = {2006}, month = {Apr}, abstract = {Whether masked words can be processed at a semantic level remains a controversial issue in cognitive psychology. Although recent behavioral studies have demonstrated masked semantic priming for number words, attempts to generalize this finding to other categories of words have failed. Here, as an alternative to subliminal priming, we introduce a sensitive behavioral method to detect nonconscious semantic processing of words. The logic of this method consists of presenting words close to the threshold for conscious perception and examining whether their semantic content modulates performance in objective and subjective tasks. Our results disclose two independent sources of modulation of the threshold for access to consciousness. First, prior conscious perception of words increases the detection rate of the same words when they are subsequently presented with stronger masking. Second, the threshold for conscious access is lower for emotional words than for neutral ones, even for words that have not been previously consciously perceived, thus implying that written words can receive nonconscious semantic processing.}, doi = {10.1073/pnas.0600584103}, pdf = {http://www.unicog.org/publications/GaillardDehaene_NonconsciousEmotionalWordsThresholdModulation_PNAS2006.pdf}, keywords = {16648261}, owner = {dehaene}, pii = {0600584103}, pmid = {16648261}, timestamp = {2006.05.10}, url = {http://dx.doi.org/10.1073/pnas.0600584103} } @ARTICLE{Gaillard2006, author = {Raphaël Gaillard and Lionel Naccache and Philippe Pinel and Stéphane Clémenceau and Emmanuelle Volle and Dominique Hasboun and Sophie Dupont and Michel Baulac and Stanislas Dehaene and Claude Adam and Laurent Cohen}, title = {{D}irect intracranial, {FMRI}, and lesion evidence for the causal role of left inferotemporal cortex in reading.}, journal = {Neuron}, year = {2006}, volume = {50}, pages = {191--204}, number = {2}, month = {Apr}, abstract = {Models of the "visual word form system" postulate that a left occipitotemporal region implements the automatic visual word recognition required for efficient reading. This theory was assessed in a patient in whom reading was explored with behavioral measures, fMRI, and intracranial local field potentials. Prior to surgery, when reading was normal, fMRI revealed a normal mosaic of ventral visual selectivity for words, faces, houses, and tools. Intracranial recordings demonstrated that the left occipitotemporal cortex responded with a short latency to conscious but also to subliminal words. Surgery removed a small portion of word-responsive occipitotemporal cortex overlapping with the word-specific fMRI activation. The patient developed a marked reading deficit, while recognition of other visual categories remained intact. Furthermore, in the post-surgery fMRI map of visual cortex, only word-specific activations disappeared. Altogether, these results provide direct evidence for the causal role of the left occipitotemporal cortex in the recognition of visual words.}, doi = {10.1016/j.neuron.2006.03.031}, pdf = {http://www.unicog.org/publications/GaillardCohen_IntracranialfMRIreadingAlexia_Neuron2006.pdf}, keywords = {16630832}, owner = {dehaene}, pii = {S0896-6273(06)00228-5}, pmid = {16630832}, timestamp = {2006.05.10}, url = {http://dx.doi.org/10.1016/j.neuron.2006.03.031} } @ARTICLE{Gliga2006, author = {Teodora Gliga and Ghislaine Dehaene-Lambertz}, title = {{D}evelopment of a view-invariant representation of the human head.}, journal = {Cognition}, year = {2006}, month = {Feb}, abstract = {Do infants perceive visual cues as diverse as frontal-view faces, profiles or bodies as being different aspects of the same object, a fellow human? If that is the case, visual exposure to one such cue should facilitate the subsequent processing of the others. To verify this hypothesis, we recorded event-related responses in 4-month-old infants and in adults. Pictures of eyes were interleaved amongst images belonging to three human contexts (frontal-view faces, profiles or bodies) or non-human contexts (houses, cars or pliers). In adults, both profile and frontal-face contexts elicited suppression of the N170 response to eye pictures, indicating an access to a view-invariant representation of faces. In infants, a response suppression of the N290 component was recorded only in the context of frontal faces, while profile context induces a different effect (i.e., a P400 enhancement) on eye processing. This dissociation suggests that the view-invariant representation of faces is learned, as it is for other 3-D objects and needs more than 4 months of exposure to be established. In a follow-up study, where infants were exposed to a short movie showing people rotating their heads, the profile-induced P400 effect was speeded up, indicating that exposure to successive views of the same object is probably a way to build up adult-like face representations.}, doi = {10.1016/j.cognition.2006.01.004}, pdf = {http://www.unicog.org/publications/GligaDehaene_PrimingFaces_Cognition2006.pdf}, keywords = {16488406}, owner = {gdehaene}, pii = {S0010-0277(06)00018-7}, pmid = {16488406}, timestamp = {2006.06.27}, url = {http://dx.doi.org/10.1016/j.cognition.2006.01.004} } @ARTICLE{Golestani2006, author = {Narly Golestani and F-Xavier Alario and Sébastien Meriaux and Denis Le Bihan and Stanislas Dehaene and Christophe Pallier}, title = {{S}yntax production in bilinguals.}, journal = {Neuropsychologia}, year = {2006}, volume = {44}, pages = {1029--1040}, number = {7}, abstract = {We used fMRI to examine the functional correlates of syntactical processing in the first (L1) and second (L2) languages of non-proficient, late bilinguals. Subjects either covertly read words or produced sentences from them. Syntactical production during sentence production activated regions including left inferior frontal (LIFG) gyrus and the supplementary motor area in both languages. Analyses performed on the LIFG activation identified on a subject-by-subject basis revealed greater activation in L2 compared to L1 during sentence production and during word reading, consistent with previous work suggesting that greater cognitive effort may be subserved by less well-tuned neural representations that require greater neuronal activity. Remarkably, there was a greater separation in the LIFG activations in L1 versus L2 in less compared to more proficient bilinguals during syntax production, suggesting a functional reorganisation of regions involved in syntactical production as a function of syntactical proficiency.}, doi = {10.1016/j.neuropsychologia.2005.11.009}, pdf = {http://www.pallier.org/papers/GolestaniPallier.syntax.bilinguals.neuropsychologia.pdf}, owner = {chrplr}, pii = {S0028-3932(05)00358-1}, pmid = {16427099}, timestamp = {2006.05.31}, url = {http://dx.doi.org/10.1016/j.neuropsychologia.2005.11.009} } @ARTICLE{Gutkin2006, author = {Boris S Gutkin and Stanislas Dehaene and Jean-Pierre Changeux}, title = {{A} neurocomputational hypothesis for nicotine addiction.}, journal = {Proc Natl Acad Sci U S A}, year = {2006}, volume = {103}, pages = {1106--1111}, number = {4}, month = {Jan}, abstract = {We present a hypothetical neurocomputational model that combines a set of neural circuits at the molecular, cellular, and system levels and accounts for several neurobiological and behavioral processes leading to nicotine addiction. We propose that combining changes in the nicotinic receptor response, expressed by mesolimbic dopaminergic neurons, with dopamine-gated learning in action-selection circuits, suffices to capture the acquisition of nicotine addiction. We show that an opponent process enhanced by persistent nicotine-taking renders self-administration rigid and habitual by inhibiting the learning process, resulting in long-term impairments in the absence of the drug. The model implies distinct thresholds on the dosage and duration for the acquisition and persistence of nicotine addiction. Our hypothesis unites a number of prevalent ideas on nicotine action into a coherent formal network for further understanding of compulsive drug addiction.}, doi = {10.1073/pnas.0510220103}, pdf = {http://www.unicog.org/publications/GutkinDehaeneChangeux_NeuronalModelNicotinicAddiction_Pnas2006.pdf}, keywords = {16415156}, owner = {dehaene}, pii = {0510220103}, pmid = {16415156}, timestamp = {2006.03.02}, url = {http://dx.doi.org/10.1073/pnas.0510220103} } @ARTICLE{Kleinschmidt2006a, author = {Andreas Kleinschmidt}, title = {Cognitive control signals in visual cortex: flashes meet spotlights.}, journal = {Neuron}, year = {2006}, volume = {51}, pages = {9--11}, number = {1}, month = {Jul}, abstract = {At the intersection of two intensely belabored fields, primary visual cortex (V1) function and neural mechanisms of cognitive control, Jack et al. (in this issue of Neuron) report a neural signal that is neither related to stimulus representation nor spatial attention. Instead, this endogenous signal correlates with task structure and raises new questions.}, doi = {10.1016/j.neuron.2006.06.010}, pdf = {http://www.unicog.org/publications/Kleinschmidt.neuron.2006.pdf}, keywords = {Afferent Pathways; Animals; Attention; Cognition; Humans; Neurons; Photic Stimulation; Psychomotor Performance; Synaptic Transmission; Thalamus; Visual Cortex; Visual Perception}, owner = {chrplr}, pii = {-6}, pmid = {16815327}, timestamp = {2007.01.23}, url = {http://dx.doi.org/10.1016/j.neuron.2006.06.010} } @ARTICLE{Kleinschmidt2006, author = {Andreas Kleinschmidt and Laurent Cohen}, title = {The neural bases of prosopagnosia and pure alexia: recent insights from functional neuroimaging.}, journal = {Curr Opin Neurol}, year = {2006}, volume = {19}, pages = {386--391}, number = {4}, month = {Aug}, abstract = {PURPOSE OF REVIEW: To discuss whether recent functional neuroimaging results can account for clinical phenomenology in visual associative agnosias. RECENT FINDINGS: Functional neuroimaging studies in healthy human subjects have identified only two regions of ventral occipitotemporal cortex that invariantly respond to individual faces and visual words, respectively. The signature of face identity coding in the fusiform neural response was shown to be missing in a patient with prosopagnosia. Another case study established that a surgical lesion close to the region sensitive to visual words can result in pure alexia. SUMMARY: Evidence is increasing that functional specialization for processing face identity and visual word forms is restricted to two specialized sensory modules in the occipitotemporal cortex. A structural or functional lesion to face-sensitive and word-sensitive regions in the ventral occipitotemporal cortex can provide the most parsimonious account for the clinical syndromes of prosopagnosia and agnosic alexia. This review suggests that functional specialization should be considered in terms of whether exclusively one brain region (instead of many) underpins a defined function and not as whether this brain region underpins exclusively one cognitive function. Such functional specialization seems to exist for at least two higher-order visual perceptual functions, face and word identification.}, doi = {10.1097/01.wco.0000236619.89710.ee}, pdf = {http://www.unicog.org/publications/kleinschmidt_cohen_curropinneurol2006.pdf}, keywords = {Dyslexia; Humans; Magnetic Resonance Imaging; Prosopagnosia; Reading; Recognition (Psychology)}, owner = {chrplr}, pii = {00019052-200608000-00010}, pmid = {16914978}, timestamp = {2007.01.23}, url = {http://dx.doi.org/10.1097/01.wco.0000236619.89710.ee} } @ARTICLE{Kouider2006, author = {Sid Kouider and Stanislas Dehaene and Antoinette Jobert and Denis Le Bihan}, title = {Cerebral Bases of Subliminal and Supraliminal Priming during Reading.}, journal = {Cereb Cortex}, year = {2006}, month = {Nov}, abstract = {Several studies have investigated the neural correlates of conscious perception by contrasting functional magnetic resonance imaging (fMRI) activation to conscious and nonconscious visual stimuli. The results often reveal an amplification of posterior occipito-temporal activation and its extension into a parieto-frontal network. However, some of these effects might be due to a greater deployment of attentional or strategical processes in the conscious condition. Here, we examined the brain activity evoked by visible and invisible stimuli, both of which were irrelevant to the task. We collected fMRI data in a masking paradigm in which subliminal versus supraliminal letter strings were presented as primes while subjects focused attention on another subsequent, highly visible target word. Under those conditions, prime visibility was associated with greater activity confined to bilateral posterior occipito-temporal cortices, without extension into frontal and parietal cortices. However, supraliminal primes, compared with subliminal primes, evoked more extensive repetition suppression in a widely distributed set of parieto-frontal areas. Furthermore, only supraliminal primes caused phonological repetition enhancement in left inferior frontal and anterior insular cortex. Those results suggest a 2-stage view of conscious access: Relative to masked stimuli, unmasked stimuli elicit increased occipito-temporal activity, thus allowing them to compete for global conscious access and to induce priming in multiple distant areas. In the absence of attention, however, their access to a second stage of distributed parieto-frontal processing may remain blocked.}, doi = {10.1093/cercor/bhl110}, pdf = {http://www.unicog.org/publications/KouiderDehaene_SubliminalSupraliminalPriming_CerebralCortex2007.pdf}, owner = {chrplr}, pii = {bhl110}, pmid = {17101688}, timestamp = {2007.06.27}, url = {http://dx.doi.org/10.1093/cercor/bhl110} } @ARTICLE{Landmann2006, author = {Claire Landmann and Stanislas Dehaene and Sabina Pappata and Antoinette Jobert and Michel Bottlaender and Dimitri Roumenov and Denis Le Bihan}, title = {Dynamics of Prefrontal and Cingulate Activity during a Reward-Based Logical Deduction Task.}, journal = {Cereb Cortex}, year = {2006}, month = {May}, abstract = {We used behavioral and functional magnetic resonance imaging (fMRI) methods to probe the cerebral organization of a simple logical deduction process. Subjects were engaged in a motor trial-and-error learning task, in which they had to infer the identity of an unknown 4-key code. The design of the task allowed subjects to base their inferences not only on the feedback they received but also on the internal deductions that it afforded (autoevaluation). fMRI analysis revealed a large bilateral parietal, prefrontal, cingulate, and striatal network that activated suddenly during search periods and collapsed during ensuing periods of sequence repetition. Fine-grained analyses of the temporal dynamics of this search network indicated that it operates according to near-optimal rules that include 1) computation of the difference between expected and obtained rewards and 2) anticipatory deductions that predate the actual reception of positive reward. In summary, the dynamics of effortful mental deduction can be tracked with fMRI and relate to a distributed network engaging prefrontal cortex and its interconnected cortical and subcortical regions.}, doi = {10.1093/cercor/bhk028}, pdf = {http://www.unicog.org/publications/LandmannDehaene_SearchRoutinefMRI_CerebCortex2006.pdf}, owner = {chrplr}, pii = {bhk028}, pmid = {16707739}, timestamp = {2007.01.23}, url = {http://dx.doi.org/10.1093/cercor/bhk028} } @ARTICLE{Laufs2006, author = {H. Laufs and John L Holt and Robert Elfont and Michael Krams and Joseph S Paul and K. Krakow and A. Kleinschmidt}, title = {Where the BOLD signal goes when alpha EEG leaves.}, journal = {Neuroimage}, year = {2006}, volume = {31}, pages = {1408--1418}, number = {4}, month = {Jul}, abstract = {Previous studies using simultaneous EEG and fMRI recordings have yielded discrepant results regarding the topography of brain activity in relation to spontaneous power fluctuations in the alpha band of the EEG during eyes-closed rest. Here, we explore several possible explanations for this discrepancy by re-analyzing in detail our previously reported data. Using single subject analyses as a starting point, we found that alpha power decreases are associated with fMRI signal increases that mostly follow two distinct patterns: either 'visual' areas in the occipital lobe or 'attentional' areas in the frontal and parietal lobe. On examination of the EEG spectra corresponding to these two fMRI patterns, we found greater relative theta power in sessions yielding the 'visual' fMRI pattern during alpha desynchronization and greater relative beta power in sessions yielding the 'attentional' fMRI pattern. The few sessions that fell into neither pattern featured the overall lowest theta and highest beta power. We conclude that the pattern of brain activation observed during spontaneous power reduction in the alpha band depends on the general level of brain activity as indexed over a broader spectral range in the EEG. Finally, we relate these findings to the concepts of 'resting state' and 'default mode' and discuss how - as for sleep - EEG-based criteria might be used for staging brain activity during wakefulness.}, doi = {10.1016/j.neuroimage.2006.02.002}, pdf = {http://www.unicog.org/publications/Laufs.Neuroimage.2006.pdf}, keywords = {Alpha Rhythm; Arousal; Brain Mapping; Data In; Electroencephalography; Frontal Lobe; Hemodynamic Processes; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Oxygen; Principal Component Analysis; Regression Analysis; terpretation, Statistical}, owner = {chrplr}, pii = {S1053-8119(06)00098-X}, pmid = {16537111}, timestamp = {2007.02.08}, url = {http://dx.doi.org/10.1016/j.neuroimage.2006.02.002} } @ARTICLE{Meriaux2006, author = {Sébastien Mériaux and Alexis Roche and Ghislaine Dehaene-Lambertz and Bertrand Thirion and Jean-Baptiste Poline}, title = {{C}ombined permutation test and mixed-effect model for group average analysis in f{MRI}.}, journal = {Hum Brain Mapp}, year = {2006}, volume = {27}, pages = {402--410}, number = {5}, month = {May}, abstract = {In group average analyses, we generalize the classical one-sample t test to account for heterogeneous within-subject uncertainties associated with the estimated effects. Our test statistic is defined as the maximum likelihood ratio corresponding to a Gaussian mixed-effect model. The test's significance level is calibrated using the same sign permutation framework as in Holmes et al., allowing for exact specificity control under a mild symmetry assumption about the subjects' distribution. Because our likelihood ratio test does not rely on homoscedasticity, it is potentially more sensitive than both the standard t test and its permutation-based version. We present results from the Functional Imaging Analysis Contest 2005 dataset to support this claim. Hum Brain Mapp 27:402-410, 2006. (c) 2006 Wiley-Liss, Inc.}, doi = {10.1002/hbm.20251}, pdf = {http://www.unicog.org/publications/MeriauxRoche&al_StatFiac_HBM2006.pdf}, keywords = {16596617}, owner = {dehaene}, pmid = {16596617}, timestamp = {2006.05.10}, url = {http://dx.doi.org/10.1002/hbm.20251} } @ARTICLE{New2006, author = {Boris New and Ludovic Ferrand and Christophe Pallier and Marc Brysbaert}, title = {{R}eexamining the word length effect in visual word recognition: new evidence from the {E}nglish {L}exicon {P}roject.}, journal = {Psychon Bull Rev}, year = {2006}, volume = {13}, pages = {45--52}, number = {1}, month = {Feb}, abstract = {In the present study, we reexamined the effect of word length (number of letters in a word) on lexical decision. Using the English Lexicon Project, which is based on a large data set of over 40,481 words (Balota et al., 2002), we performed simultaneous multiple regression analyses on a selection of 33,006 English words (ranging from 3 to 13 letters in length). Our analyses revealed an unexpected pattern of results taking the form of a U-shaped curve. The effect of number of letters was facilitatory for words of 3-5 letters, null for words of 5-8 letters, and inhibitory for words of 8-13 letters. We also showed that printed frequency, number of syllables, and number of orthographic neighbors all made independent contributions. The length effects were replicated in a new analysis of a subset of 3,833 monomorphemic nouns (ranging from 3 to 10 letters), and also in another analysis based on 12,987 bisyllabic items (ranging from 3 to 9 letters). These effects were independent of printed frequency, number of syllables, and number of orthographic neighbors. Furthermore, we also observed robust linear inhibitory effects of number of syllables. Implications for models of visual word recognition are discussed.}, pdf = {http://www.pallier.org/papers/New.PBR-2006.pdf}, owner = {chrplr}, pmid = {16724767}, timestamp = {2006.05.31} } @ARTICLE{Piazza2006a, author = {Manuela Piazza and Andrea Mechelli and Cathy J Price and Brian Butterworth}, title = {Exact and approximate judgements of visual and auditory numerosity: an fMRI study.}, journal = {Brain Res}, year = {2006}, volume = {1106}, pages = {177--188}, number = {1}, month = {Aug}, abstract = {Human adults can assess the number of objects in a set (numerosity) by approximate estimation or by exact counting. There is evidence suggesting that numerosity estimation depends on a dedicated mechanism that is a-modal and non-verbal. By contrast, counting requires the coordination between the pre-existing numerosity estimation abilities with language and one-to-one correspondence principles. In this paper we investigate with fMRI the neural correlates of numerosity estimation and counting in human adults, using both visual and auditory stimuli. Results show that attending to approximate numerosity correlates with increased activity of a right lateralized fronto-parietal cortical network, and that this activity is independent of the stimuli presentation's modality. Counting activates additional left prefrontal, parietal, and bilateral premotor areas, again independently from stimulus modality. These results dissociate two neuronal systems that underlie different numerosity judgements.}, doi = {10.1016/j.brainres.2006.05.104}, keywords = {Acoustic Stimulation; Adult; Auditory Perception; Brain Mapping; Cerebral Cortex; Female; Frontal Lobe; Functional Laterality; Humans; Judgment; Magnetic Resonance Imaging; Male; Mathematics; Nerve Net; Neural Pathways; Neuropsychological Tests; Parietal Lobe; Photic Stimulation; Visual Perception}, owner = {chrplr}, pii = {S0006-8993(06)01585-X}, pmid = {16828717}, timestamp = {2007.01.23}, url = {http://dx.doi.org/10.1016/j.brainres.2006.05.104} } @ARTICLE{Piazza2006, author = {Manuela Piazza and Philippe Pinel and Stanislas Dehaene}, title = {Objective correlates of an unusual subjective experience: A single-case study of number?form synaesthesia}, journal = {Cognitive Neuropsychology}, year = {2006}, volume = {23}, pages = {1162--1173}, number = {8}, abstract = {There is a universal and often unconscious tendency to mentally associate the number sequence with a spatial continuum (the mental number line). Here we study one individual who reports a strong and vivid sense of space when processing numbers. For him, the number sequence has a precise spatial form: a curvilinear right-to-left oriented line. We used various tasks to demonstrate that this numerical - spatial association is not a mere figment of his imagination, but a constrained experiential phenomenon consistent across sessions and automatically triggered by the visual presentation of numbers. We also show that this idiosyncratic representation can coexist with another implicit association, the SNARC effect (Spatial?Numerical Association of Response Codes, where small numbers are associated with the left side of space). This effect is present in individuals without explicit number forms and is not affected in the present subject in spite of his reversed subjective representation.}, pdf = {http://www.unicog.org/publications/Piazza_NumberFormCognNeuropsych2006.pdf}, owner = {chrplr}, timestamp = {2007.01.23} } @ARTICLE{Plaze2006, author = {Marion Plaze and David Bartrés-Faz and Jean-Luc Martinot and Dominique Januel and Franck Bellivier and Renaud De Beaurepaire and Sandra Chanraud and Jamila Andoh and Jean-Pascal Lefaucheur and Eric Artiges and Christophe Pallier and Marie-Laure Paillère-Martinot}, title = {{L}eft superior temporal gyrus activation during sentence perception negatively correlates with auditory hallucination severity in schizophrenia patients.}, journal = {Schizophr Res}, year = {2006}, month = {Jul}, abstract = {The left superior temporal cortex, which supports linguistic functions, has consistently been reported to activate during auditory-verbal hallucinations in schizophrenia patients. It has been suggested that auditory hallucinations and the processing of normal external speech compete for common neurophysiological resources. We tested the hypothesis of a negative relationship between the clinical severity of hallucinations and local brain activity in posterior linguistic regions while patients were listening to external speech. Fifteen right-handed patients with schizophrenia and daily auditory hallucinations for at least 3 months were studied with event-related fMRI while listening to sentences in French or to silence. Severity of hallucinations, assessed using the auditory hallucination subscales of the Psychotic Symptom Rating Scales (PSYRATS) and of the Scale for the Assessment of Positive Symptoms (SAPS-AH), negatively correlated with activation in the left temporal superior region in the French minus silence condition. This finding supports the hypothesis that auditory hallucinations compete with normal external speech for processing sites within the temporal cortex in schizophrenia.}, doi = {5.005}, pdf = {http://www.pallier.org/papers/Plaze.schizo.2006.pdf}, owner = {chrplr}, pii = {S0920-9964(06)00231-3}, pmid = {16828542}, timestamp = {2006.07.13}, url = {http://dx.doi.org/5.005} } @ARTICLE{Poline2006, author = {Jean-Baptiste Poline and Stephen C Strother and Ghislaine Dehaene-Lambertz and Gary F Egan and Jack L Lancaster}, title = {{M}otivation and synthesis of the {FIAC} experiment: {R}eproducibility of f{MRI} results across expert analyses.}, journal = {Hum Brain Mapp}, year = {2006}, volume = {27}, pages = {351--359}, number = {5}, month = {May}, abstract = {The Functional Imaging Analysis Contest (FIAC) culminated in the FIAC Workshop held at the 11th Annual Meeting of the Organization for Human Brain Mapping in Toronto in 2005. This special issue summarizes various analyses used by contestants with a single functional magnetic resonance imaging (fMRI) study, a cortical-language study using sentence repetition. The results from the cognitive neuroscientists who developed the test-base language study, and report their data analysis, are complemented by expert analyses of the same test-base data by most of the major groups actively developing fMRI software packages. Analyses include many variants of the general linear model (GLM), cutting-edge spatial- and temporal-wavelets, permutation-based, and ICA approaches. A number of authors also include surface-based approaches. Several articles describe the important emerging areas of diagnostics for GLM analysis, multivariate predictive modeling, and functional connectivity analysis. While the FIAC did not achieve all of its goals, it helped identify new activation regions in the test-base data, and more important, through this special issue it illustrates the significant methods-driven variability that potentially exists in the literature. Variable results from different methods reported here should provide a cautionary note and motivate the Human Brain Mapping community to explore more thoroughly the methodologies they use for analyzing fMRI data. Hum Brain Mapp 27:351-359, 2006. (c) 2006 Wiley-Liss, Inc.}, doi = {10.1002/hbm.20268}, keywords = {16583364}, owner = {dehaene}, pmid = {16583364}, timestamp = {2006.05.10}, url = {http://dx.doi.org/10.1002/hbm.20268} } @ARTICLE{Thirion2006, author = {Bertrand Thirion and Edouard Duchesnay and Edward Hubbard and Jessica Dubois and Jean-Baptiste Poline and Denis Lebihan and Stanislas Dehaene}, title = {Inverse retinotopy: inferring the visual content of images from brain activation patterns.}, journal = {Neuroimage}, year = {2006}, volume = {33}, pages = {1104--1116}, number = {4}, month = {Dec}, abstract = {Traditional inference in neuroimaging consists in describing brain activations elicited and modulated by different kinds of stimuli. Recently, however, paradigms have been studied in which the converse operation is performed, thus inferring behavioral or mental states associated with activation images. Here, we use the well-known retinotopy of the visual cortex to infer the visual content of real or imaginary scenes from the brain activation patterns that they elicit. We present two decoding algorithms: an explicit technique, based on the current knowledge of the retinotopic structure of the visual areas, and an implicit technique, based on supervised classifiers. Both algorithms predicted the stimulus identity with significant accuracy. Furthermore, we extend this principle to mental imagery data: in five data sets, our algorithms could reconstruct and predict with significant accuracy a pattern imagined by the subjects.}, doi = {10.1016/j.neuroimage.2006.06.062}, pdf = {http://www.unicog.org/publications/ThirionDehaene_InverseRetinotopy_Neuroimage2006.pdf}, keywords = {Humans; Imagination; Magnetic Resonance Imaging; Models, Theoretical; Retina; Visual Cortex; Visual Perception}, owner = {chrplr}, pii = {S1053-8119(06)00737-3}, pmid = {17029988}, timestamp = {2007.06.27}, url = {http://dx.doi.org/10.1016/j.neuroimage.2006.06.062} } @ARTICLE{Vinckier2006, author = {Fabien Vinckier and Lionel Naccache and Caroline Papeix and Joaquim Forget and Valerie Hahn-Barma and Stanislas Dehaene and Laurent Cohen}, title = {"What" and "where" in word reading: ventral coding of written words revealed by parietal atrophy.}, journal = {J Cogn Neurosci}, year = {2006}, volume = {18}, pages = {1998--2012}, number = {12}, month = {Dec}, abstract = {The visual system of literate adults develops a remarkable perceptual expertise for printed words. To delineate the aspects of this competence intrinsic to the occipitotemporal "what" pathway, we studied a patient with bilateral lesions of the occipitoparietal "where" pathway. Depending on critical geometric features of the display (rotation angle, letter spacing, mirror reversal, etc.), she switched from a good performance, when her intact ventral pathway was sufficient to encode words, to severely impaired reading, when her parietal lesions prevented the use of alternative reading strategies as a result of spatial and attentional impairments. In particular, reading was disrupted (a) by rotating word by more than 50 degrees , providing an approximation of the invariance range for words encoding in the ventral pathway; (b) by separating letters with double spaces, revealing the limits of letter grouping into perceptual wholes; (c) by mirror-reversing words, showing that words escape the default mirror-invariant representation of visual objects in the ventral pathway. Moreover, because of her parietal lesions, she was unable to discriminate mirror images of common objects, although she was excellent with reversible pseudowords, confirming that the breaking of mirror symmetry was intrinsic to the occipitotemporal cortex. Thus, charting the display conditions associated with preserved or impaired performance allowed us to infer properties of word coding in the normal ventral pathway and to delineate the roles of the parietal lobes in single-word recognition.}, doi = {10.1162/jocn.2006.18.12.1998}, pdf = {http://www.unicog.org/publications/vinckier_cohen_what-and-where-in-reading_JOCN2006.pdf}, owner = {chrplr}, pmid = {17129187}, timestamp = {2007.01.23}, url = {http://dx.doi.org/10.1162/jocn.2006.18.12.1998} } @ARTICLE{Wilson2006a, author = {Anna Juliet Wilson and Stanislas Dehaene and Philippe Pinel and Susannah Revkin and Laurent Cohen and David Cohen}, title = {Principles underlying the design of "The Number Race", an adaptive computer game for remediation of dyscalculia}, journal = {Behav Brain Funct}, year = {2006}, volume = {2}, pages = {19}, number = {1}, abstract = {ABSTRACT: BACKGROUND: Adaptive game software has been successful in remediation of dyslexia. Here we describe the cognitive and algorithmic principles underlying the development of similar software for dyscalculia. Our software is based on current understanding of the cerebral representation of number and the hypotheses that dyscalculia is due to a "core deficit" in number sense or in the link between number sense and symbolic number representations. METHODS: "The Number Race" software trains children on an entertaining numerical comparison task, by presenting problems adapted to the performance level of the individual child. We report full mathematical specifications of the algorithm used, which relies on an internal model of the child's knowledge in a multidimensional "learning space" consisting of three difficulty dimensions: numerical distance, response deadline, and conceptual complexity (from non-symbolic numerosity processing to increasingly complex symbolic operations). RESULTS: The performance of the software was evaluated both by mathematical simulations and by five weeks of use by nine children with mathematical learning difficulties. The results indicate that the software adapts well to varying levels of initial knowledge and learning speeds. Feedback from children, parents and teachers was positive. A companion article 1 describes the evolution of number sense and arithmetic scores before and after training. CONCLUSION: The software, open-source and freely available online, is designed for learning disabled children aged 5-8, and may also be useful for general instruction of normal preschool children. The learning algorithm reported is highly general, and may be applied in other domains.}, doi = {10.1186/1744-9081-2-19}, pdf = {http://www.unicog.org/publications/wilson_NumberRace_bbf_2_2006.pdf}, owner = {chrplr}, pii = {1744-9081-2-19}, pmid = {16734905}, timestamp = {2007.01.24}, url = {http://dx.doi.org/10.1186/1744-9081-2-19} } @ARTICLE{Wilson2006, author = {Anna Juliet Wilson and Susannah Revkin and David Cohen and Laurent Cohen and Stanislas Dehaene}, title = {An open trial assessment of "{T}he {N}umber {R}ace", an adaptive computer game for remediation of dyscalculia}, journal = {Behav Brain Funct}, year = {2006}, volume = {2}, pages = {20}, number = {1}, abstract = {ABSTRACT: BACKGROUND: In a companion article 1, we described the development and evaluation of software designed to remediate dyscalculia. This software is based on the hypothesis that dyscalculia is due to a "core deficit" in number sense or in its access via symbolic information. Here we review the evidence for this hypothesis, and present results from an initial open-trial test of the software in a sample of nine 7-9 year old children with mathematical difficulties. METHODS: Children completed adaptive training on numerical comparison for half an hour a day, four days a week over a period of five-weeks. They were tested before and after intervention on their performance in core numerical tasks: counting, transcoding, base-10 comprehension, enumeration, addition, subtraction, and symbolic and non-symbolic numerical comparison. RESULTS: Children showed specific increases in performance on core number sense tasks. Speed of subitizing and numerical comparison increased by several hundred msec. Subtraction accuracy increased by an average of 23\%. Performance on addition and base-10 comprehension tasks did not improve over the period of the study. CONCLUSION: Initial open-trial testing showed promising results, and suggested that the software was successful in increasing number sense over the short period of the study. However these results need to be followed up with larger, controlled studies. The issues of transfer to higher-level tasks, and of the best developmental time window for intervention also need to be addressed.}, doi = {10.1186/1744-9081-2-20}, pdf = {http://www.unicog.org/publications/wilson_NumberRace_bbf_1_2006.pdf}, owner = {chrplr}, pii = {1744-9081-2-20}, pmid = {16734906}, timestamp = {2007.01.24}, url = {http://dx.doi.org/10.1186/1744-9081-2-20} } @INPROCEEDINGS{pallier_jep2006, author = {Christophe Pallier}, title = {Imagerie cérébrale du bilinguisme et de l'apprentissage des langues}, booktitle = {Actes des {XXVI}e journées d'études sur la parole (JEP)}, year = {2006}, editor = {Frédéric Bimbot}, pages = {555--556}, note = {Dinard}, pdf = {http://www.pallier.org/papers/pallier_jep2006.pdf}, owner = {chrplr}, timestamp = {2007.03.02} } @BOOK{Dehaene2005c, title = {From Monkey Brain to Human Brain. A Fyssen Foundation Symposium.}, publisher = {MIT Press}, year = {2005}, author = {Dehaene, Stanislas and Duhamel, Jean-René and Hauser, Marc D. and Rizzolatti, Giacomo}, pdf = {http://www.unicog.org/publications/DehaeneFyssenChapterPreemption2004b.pdf}, owner = {dehaene}, timestamp = {2005.09.20} } @PHDTHESIS{Sergent2005a, author = {Claire Sergent}, title = {Dynamique de l'accès à la conscience : caractérisation comportementale et bases neurales de l'accès à la conscience lors du clignement attentionnel ("attentional blink")}, school = {Université Paris XI}, year = {2005}, type = {Thesis/Dissertation}, note = {supervised by Stanislas Dehaene}, keywords = {vision; conscience; accès à la conscience; attention; dynamique; clignement attentionnel; psychologie expérimentale; électro-encéphalographie}, owner = {chrplr}, timestamp = {2007.01.24} } @PHDTHESIS{Ventureyra2005, author = {Val{\'e}rie Ventureyra}, title = {{\`A} la recherche de la langue perdue: {\'e}tude psycholinguistique de l'attrition de la premi{\`e}re langue chez des cor{'e}ens adopt{\'e}s en {F}rance}, school = {{\'E}cole des hautes {\'e}tudes en sciences sociales}, year = {2005}, type = {Thesis/Dissertation}, address = {Paris}, month = {Jan}, note = {supervised by Christophe Pallier}, abstract = {L'exposition à une langue pendant l'enfance laisse-t-elle des traces indélébiles dans le cerveau ? Est-ce possible qu'une seconde langue (L2) "remplace" une première langue (L1), dans des circonstances particulières ? L'hypothèse de la période critique pour l'acquisition du langage prédit que les aires langagières du cerveau perdent la plasticité avec l'âge. Une conséquence de cette hypothèse est donc que l'exposition à une langue donnée pendant les premières années de vie laissera des traces permanentes dans le cerveau. Ceci implique que la perte complète d'une langue maternelle ne pourrait avoir lieu. L'autre conséquence de la perte de plasticité est la difficulté croissante en fonction de l'âge de l'apprenant. Des études de l'acquisition d'une deuxième langue et des cas de personnes privées de langage pendant les premières années de vie (les "enfants-loups" et parfois les sourds nés dans des familles d' entendants) portent des preuves en faveur de la perte de plasticité. Dans cette thèse nous explorons les traces éventuelles de la L1 apprise et `perdue'pendant l'enfance, et la compétence dans la L2 apprise plus tard dans l'enfance. Nous avons choisi d'étudier des adoptés d'origine étrangère pour examiner ces questions. Notre étude concerne des adultes d'origine coréenne adoptés par des familles francophones entre l'âge de 3 et 10 ans et ayant été complètement isolés de leur langue et culture d'origine depuis leur arrivé en France il y a 15 à 30 ans. Cette thèse comporte trois parties : 1.) la recherche de traces de mémoire linguistique et autres (reconnaissance de séries numériques, de mots, de séries de jours de la semaine, de morphologie faciale) ; 2.) la recherche de traces éventuelles de la phonologie du coréen (discrimination de phonèmes, entraînement aux sons du coréen) et 3.) l'évaluation de certains aspects du français (genre grammatical , phonotactique). Nous avons comparé les résultats des adoptés à ceux de francophones sans connaissances du coréen dans chaque expérience, et à ceux de Coréens natifs résidant en France pour certaines expériences. Les expériences de mémoire ont révélé l'existence de très peu de traces du coréen et d'autres types de souvenirs. De la même façon, les expériences de phonologie du coréen ont montré un comportement similaire à celui des francophones, et ceci indépendamment de la réexposition de certains adoptés à la langue coréenne lors de séjours de courte durée en Corée. Ces résultats nous suggèrent soit une perte du coréen, soit une inaccessibilité importante à cette langue par les adoptés. Les performances des adoptés sur les tests de français sont également semblables à celles des francophones et diffèrent de celle des Coréens natifs, indiquant une bonne maîtrise des aspects du français difficiles pour des Coréens. L'ensemble des données montre que les adoptés coréens sont devenus comme des francophones natifs dans leur traitement langagier. L'important rôle joué par la plasticité du système langagier chez les adoptés est corroboré par nos résultats, qui suggèrent qu'une langue maternelle peut être facilement remplacée par une autre langue pendant l'enfance. Il y a une convergence entre nos résultats et ceux d'études de cas d'attrition langagière chez des jeunes enfants adoptés montrant que la L1 est rapidement oubliée (Nicoladis \& Grabois, 2002 ; Isurin, 2000), alors que la L2 est vite assimilée.}, pdf = {http://www.pallier.org/papers/Ventureyra.thesefinal.pdf}, owner = {chrplr}, timestamp = {2007.01.24} } @INCOLLECTION{Dehaene2005, author = {Dehaene, Stanislas}, title = {Evolution of human cortical circuits for reading and arithmetic: The "neuronal recycling" hypothesis.}, booktitle = {From Monkey Brain to Human Brain. A Fyssen Foundation Symposium.}, publisher = {MIT Press}, year = {2005}, editor = {Dehaene, Stanislas and Duhamel, Jean-René and Hauser, Marc D. and Rizzolatti, Giacomo}, chapter = {8}, pages = {133-157}, pdf = {http://www.unicog.org/publications/DehaeneFyssenChapterPreemption2004b.pdf}, owner = {dehaene}, timestamp = {2005.09.20} } @ARTICLE{Barth2005, author = {Hilary Barth and Kristen La Mont and Jennifer Lipton and Stanislas Dehaene and Nancy Kanwisher and Elizabeth Spelke}, title = {Non-symbolic arithmetic in adults and young children.}, jour