Comparative psychological test studies of the intellectual ability of Parkinson patients

Patients with Parkinson's disease (n=81) are compared with normal controls and three clinical groups, each representing a different level of cerebral impairment (TIA; Stroke; Alzheimer's disease (Ad) and multi-infarct dementia (MID). Psychometric measures of abstract reasoning, speed of information processing, verbal and visual memory, visuospatial perception and psychomotor functions are taken using a neuropsychological test battery with appropriate age-correction and normalized scaling