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Dissociative disorders, as defined in the international classification of diseases (ICD-10) as belonging to the category of functional disorders, still remain a great enigma for medicine. We will focus here on the neurobiological correlates of motor dissociative disorders, as they can be investigated through new functional neuroimaging techniques. There have been surprisingly few of such studies compared to the studies conducted on disorders such as depression or schizophrenia, probably because of the fuzzier clinical picture at the interface between neurology and psychiatry. Current research seems to demonstrate, one century after Charcot and Freud, that motor dissociative disorders are indeed associated with a dynamic functional lesion of the central nervous system. These behaviors involve brain areas directly linked to the symptoms (the motor system for example), as well as the prefrontal, limbic, and ventromedial regions. The ventromedial prefrontal cortex, involved in self- representation, together with limbic structures like the amygdale appear to modulate the motor system. Such a model partly fits the Freudian concept of conversion.