LANGUAGE, READING AND NEURAL RECYCLING (Laurent COHEN)
Our research activity revolves around the study of higher cognitive functions, particularly language and reading. A main focus of the lab has been the understanding of the Visual Word Form Area (VWFA), a region in the ventral visual cortex subtending the recognition of letters and words that can only specialize over the course of reading acquisition. One question under investigation is the cause for such a reproducible specialization for words, which may be found in its optimal wiring with language areas. Another interesting scenario is the development of this area in the congenitally blind with a sensory deprived brain that had never received visual input.
SPATIAL ATTENTION AND HEMISPATIAL NEFLECT (Paolo BARTOLOMEO)
Our research interests mainly focus on the cognitive neuroscience of visuospatial attention and high-level visual processing.
We recently showed that:
- Attention is required to produce the predictive corrections of location that are required for our accurate interactions with an ever-changing environment.
- An early, abrupt spontaneous sensory attenuation in the normal brain can determine a prolonged and dramatic consciousness state such as mind wandering.
- Left occipito-temporal areas and the callosal splenium are essential to connect color perception with mechanisms important for color categorization/naming.
- We are now investigating the neural dynamics of attention with depth electrodes implanted in the brain of patients with drug-resistant epilepsy.
CONSCIOUSNESS AND ITS DISORDERS (Lionel NACCACHE)
Our team explores consciousness level and cognitive residual abilities in patients suffering from both acute and chronic disorder of consciousness after brain injuries. We use several exploration approaches: Clinical neurology (dedicated scales), electrophysiology (EEG, Evoked Potentials), Neuro-imagery (PET-scan, MRI, functional MRI) and have begun therapeutic interventions (eg tDCS, pharmacology).
In parallel, our team also explores consciousness in healthy subjects and is particularly interested in understanding the extent to which unconscious information can influence our cognitive processes. For example, we are curently assessing wether subliminal information can have long lasting effects on attentional processes; but also whether we process regularities and irregularities of our environment at an unconscious level. Recently, we have extended our research on the perception of irregularities to the conscious level. Within this scope, and using several neuroimaging techniques (such as fMRI and sEEG), we are investigating the various mechanisms that allow us to deal with our internal inconsistencies.
- Bouhali F, Thiebaut de Schotten M, Pinel P, Poupon C, Mangin JF, Dehaene S, Cohen L. Anatomical connections of the visual word form area. J Neurosci. 2014 Nov 12;34(46):15402-14. doi: 10.1523/JNEUROSCI.4918-13.2014.
- Sitt J.D. et al. Large scale screening of neural signatures of consciousness in patients in a vegetative or minimally conscious state, Brain. 2014 Aug;137(Pt 8):2258-70
- King JR, Gramfort A, Schurger A, Naccache L, Dehaene S. Two distinct dynamic modes subtend the detection of unexpected sounds. PLoS One. 2014 Jan 27;9(1):e85791. doi: 10.1371/journal.pone.0085791. eCollection 2014.
- King JR, Sitt JD, Faugeras F, Rohaut B, El Karoui I, Cohen L,Naccache L, Dehaene S. Information sharing in the brain indexes consciousness in noncommunicative patients. Curr Biol. 2013 Oct 7;23(19):1914-9. doi: 10.1016/j.cub.2013.07.075
- Strauss M, Sitt JD, King JR, Elbaz M, Azizi L, Buiatti M, Naccache L, van Wassenhove V, Dehaene S. Disruption of hierarchical predictive coding during sleep. Proc Natl Acad Sci U S A. 2015 Mar 17;112(11):E1353-62. doi: 10.1073/pnas.1501026112
- El Karoui I, King JR, Sitt J, Meyniel F, Van Gaal S, Hasboun D, Adam C, Navarro V, Baulac M, Dehaene S, Cohen L, Naccache L. Event-Related Potential, Time-frequency, and Functional Connectivity Facets of Local and Global Auditory Novelty Processing: An Intracranial Study in Humans. Cereb Cortex. 2014 Jun 26. pii: bhu14
van Gaal S, Naccache L, Meuwese JD, van Loon AM, Leighton AH, Cohen L, Dehaene
- S. Can the meaning of multiple words be integrated unconsciously? Philos Trans R Soc Lond B Biol Sci. 2014 Mar 17;369(1641):20130212. doi: 10.1098/rstb.2013.0212.