Disturbances of rhythm formation in patients with hemispheric lesion.

A total of 191 patients with hemispheric lesion mainly due to CVD were examined by the finger-tapping test, and their disturbances of rhythm formation, 'hastening phenomenon' (HP), were compared with those of Parkinson's disease. HP was observed in 56% of the right and 49% of the left hemiplegic patients. HP in the intact hand of the patient was highly correlated with that of the affected hand. CT scans were examined in 86 of 191 patients, and HP was specifically correlated with unilateral striatal lesions. Thus, the disturbances of rhythm formation in hemiplegia, together with those in Parkinson's disease, Huntington's chorea, SND and OPCA, were attributed either to organic or functional deficits in the striatum.