A former student of the Ecole Normale Supérieure, Paris, Prof. Lionel Naccache is a neurologist and holds a PhD in cognitive neurosciences from Paris VI University. His thesis, written under the supervision of Prof. Stanislas Dehaene, is entitled “The Subliminal Perception of Numbers : Psychological Properties and Functional Brain Imaging of Unconscious Cognitive Processes". He now works both as a neurologist in the unit for nervous system diseases at Pitié – Salpêtrière in Paris, and as a professor at Paris VI University. He is co-director of the "Neuropsychology & Neuroimaging" unit (INSERM, the French National Institute of Health and Medical Research) within the ICM (Institut du Cerveau et de la Moëlle épinière). He published two essays on neurosciences of consciousness and subjectivity. His primary interest is the cerebral basis of consciousness.