Semantic memory in DAT, MID and parkinsonism.

Previous studies found the semantic system particularly affected in Dementia of Alzheimer's Type (DAT), which would have important implications for the clinical diagnosis of this disease. We compared 14 non-demented parkinsonian patients and 14 controls on one hand and demented patients suffering from multi-infarct dementia (n = 17), DAT (n = 18) and Parkinsonism + dementia (n = 7) on the other. Demented groups were well matched regarding severity of dementia. Two tasks of semantic memory (naming, word fluency) did not differentiate within demented groups, but were correlated with severity of dementia.