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Abstract:
There is evidence indicating that Alzheimer's patients
possess a category -specific deficit, demonstrating greater
difficulty processing natural kinds (e.g., cat) than artifacts
(e.g., table). Appearance and function features are thought to
contribute in varying proportions to object concepts, and a
selective impairment of these features has been hypothesized to
play a major role in explanations of category-specific deficits. It
has been assumed that this contrast between appearance and function
features is honored in the intact brain, but there is little
evidence to support this assumption. In this study, we examined
whether non-demented subjects would show a processing distinction
between appearance and function features. To this end, we tested 30
senior subjects on a feature repetition priming paradigm in which
subjects were presented with a probe item followed by a pair of
brief phrases whose truth value had to be verified (e.g., "tiger":
"does it have stripes?", "does it fly?"). Results revealed that
subjects selectively primed for successive appearance and function
features, respectively. That is, if the first item concerned
appearance, subjects were faster verifying the second item when it
also concerned appearance, and vice versa when the first item
concerned function. These results will be discussed in relation to
the category-specific deficit observed in Alzheimer's
disease.
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