Our subject was an adult male who developed cerebral thrombosis and had porencephaly at the age of two months. Although he still has mild left hemiplegia, he has matured normally. When he entered his twenties, he experienced three episodes: the first episode was that of mental confusion, the second was of stupor, and the third was of psychogenic fugue. In each case, the patient completely returned to his original state after a short period of time. We report this case in order to discuss the vulnerability of the brain as an organ in the context of atypical psychosis. Atypical psychosis is believed to be related to the pathology of consciousness and also to the vulnerability of the diencephalon, both of which were prominent in this patient.
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