Preserved verb generation priming in global amnesia.

In the verb generation task, participants are presented with nouns and generate for each one an appropriate verb. Raichle et al. (Cerebral Cortex, 1994, 4, 8-26) found that when participants generated verbs to repeated nouns, generation latencies were reduced and different patterns of brain activation were present. In order to examine whether verb generation priming is dependent or independent of declarative memory, verb generation priming was compared between 13 amnesic (seven with alcoholic Korsakoff's syndrome, six with other etiologies) and 19 control participants (10 with a history of alcoholism). Both amnesic and control participants became faster across blocks on repeated nouns and slowed when novel nouns were introduced. Priming was verb specific for both groups: it was equivalent whether generated to a repeated or a novel noun. Verb generation priming, therefore, can occur independently of declarative memory.

Evidence for multiple mechanisms of conceptual priming on implicit memory tests.

The authors examined effects of encoding manipulations on 4 conceptual-implicit memory tasks: word-cued association, category-cued association, category verification, and abstract/concrete classification. Study-phase conceptual elaboration enhanced priming for word-cued association with weakly associated words (Experiment 3), and for category-cued association with high- and low-dominance exemplars (Experiments 4 and 5), but did not enhance priming for word-cued association with strongly associated words (Experiments 1 and 2), for category verification with high- and low-dominance exemplars (Experiment 5), or for abstract/concrete classification (Experiment 7). Forms of priming that were unaffected by conceptual elaboration were not mediated by perceptual processes because they were unaffected by study-test modality changes (Experiments 6 and 8). The dissociative effects of conceptual elaboration on conceptual-implicit tasks suggest that at least 2 dissociable mechanisms mediate conceptual priming.