Jacoby-Whitehouse illusion from taxonomic and thematic associations in Alzheimer disease

Alzheimer's disease patients (AD) show an impairment of recognition memory, mainly characterized by deficient recollection. The other process supporting recognition, familiarity, is relatively preserved. Familiarity is built on fluency cues (i.e., ease of processing due to repetition) and provides a sense of the strength of a memory trace. In a word recognition task, Jacoby & Whitehouse (1989) showed that false recognitions of unlearned words can be elicited by the prior masked presentation of the same word. Such false recognitions have been replicated using semantically related primes. The specific impairment of structural links in semantic memory in Alzheimer's disease follows a hierarchical order, taxonomic links (concepts within the same category, e.g. dog-cat) being more rapidly impaired than thematic links (concepts often encountered together, e.g. hair-brush). In this word recognition task, we preceded the test word by a 33-ms prime and manipulated the type of link, either perceptual (repetition) or semantic (taxonomic, thematic), and the prime-test word relationship (related or unrelated). The experimental group, composed of 17 early-stage AD patients was contrasted with an age-matched control group. Taxonomic impairment in AD starts with the alteration of the distinctive attributes between concepts, creating a taxonomic priming effect that should be close to repetition priming. AD group was affected by early taxonomic impairment, with more false alarms in the thematic and repetition conditions than in the taxonomic. But contrary to our expectations, the taxonomic impairment did not result in hyperpriming for that condition.

Keywords: Alzheimer, recognition memory, priming, perceptive, thematic, taxonomical
Reference
Jacoby, L. L., & Whitehouse, K. (1989). An illusion of memory: False recognition influenced by unconscious perception. Journal of Experimental Psychology: General, 118(2), 126.