Behavioral symptoms after pallido-nigral lesions: a clinico-pathological case.

A 59-year-old patient presented with compulsive behaviors and lasting apathy after carbon monoxide intoxication. The apathy could be overcome by external stimulation (self-activation deficit). There was severe neuronal loss bilaterally in the anterior part of the pallidum and in the substantia nigra, pars reticulata. This first clinico-pathological case of a self-activation deficit illustrates the dissociation between motor and behavioral symptoms in lesions of the pallido-nigral complex, with the behavioral symptoms being related to lesions of the substantia nigra, pars reticulata and of the anterior part of the pallidum.