Abstract: The question of whether the age, age of onset, disease duration and severity of motor symptoms in idiopathic Parkinson’s disease(PD)is selated with the degree of intellectual deficits is still controversial. This issue was examined in a study of 31 consecutive patients with PD, utilizing quantitative clinical measures and standardized Wechsler Adult Intelligence Scale revised in China (WAIS-RC). Significant correlations were found between the severity of bradykinesia and the impaired performance on WAIS test However the degree of obvious tremor was inverselg correlated with the intellectual scores. The age, age of onset and severity of rigidity were not significantly correlated to intellectual impairments. These results suggest that the intellectual deficits may result from the same subcortical lesion that cause bradykinesia and that PD with predominant tremor could be an early symptom aor subt ypeof Parkinson’s disease with relatively intact intellectual function.

Key words: intellectual deficits, Parkinson's disease, dementia, bradykinesia, tre mor