The Extrapyramidal Disorder of Alzheimer’s Disease

65 unselected patients, referred to a neurological unit of a general hospital with organic dementia, were investigated to assess the motor disorder in this group of diseases. Extrapyramidal features of type were found in 40 of the 65 patients. The main features, akinesia, a mild dyspraxia Parkinsonism of movements of the arms and of gait, and primitive reflexes, were found in the majority of patients. Amyotrophy of the small hand muscles was found in six subjects. Assessment of associated features provided no evidence that cerebral vascular disease might be the cause of the combination of dementia with extrapyramidal features. The aetiology is discussed, and the conept of a supranuclear type of extrapyramidal disorder is postulated in these patients; it may account for certain anomalies in treatment of Parkinson’s Disease with Levodopa.