The clinical, neuropsychological and computer-aided tomography data were compared in elderly and senile patients suffering from trembling and akinetic rigid forms of parkinsonism. 12 patients with trembling and 21 with akinetic rigid parkinsonism were examined. The groups did not differ in age or sex. The results of computer-aided tomography of the brain were evaluated using linear, volumetric and densitometric parameters. The akinetic rigid pattern was found to be associated with a more diverse clinical and neuropsychological symptomatology, by more manifest cerebral atrophy. The gravity of the status of patients with trembling parkinsonism is largely determined by the intensity of the hyperkinetic syndrome, that of patients with akinetic rigid parkinsonism not only by amyostatic disturbances but also by the presence and severity of incoordination , pseudobulbar and mnemonic intellectual disorders. The disorders identified in patients with akinetic rigid parkinsonism often attest to dysfunction of the frontal parts of the brain. The nosological heterogeneity of both patterns of parkinsonism is assumed.