Semantic priming in patients with Alzheimer and semantic dementia

Semantic priming for pairs of words having semantic relation (members of the same category) but not associative relation was tested in four patients with mild Alzheimer-type dementia (AD), three patients with semantic dementia (SD) and three normal controls. Priming effects were exhibited by all the AD patients and normal controls but by none of the SD patients. The facilitation did not differ depending on whether words were written in kanji or kana. The nature of semantic deficits in AD and SD is discussed.