Cerebral Cortex Advance Access published online on December 1, 2007
Cerebral Cortex, doi:10.1093/cercor/bhm200
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Familiarity and Conceptual Priming Engage Distinct Cortical Networks
1 Interdepartmental Neuroscience Program, 2 Department of Psychology, 3 Cognitive Neurology and Alzheimer's Disease Center, 4 Department of Neurology, 5 Department of Psychiatry, 6 Department of Radiology, Northwestern University, Evanston, IL 60208-2710, USA
Address correspondence to Joel L. Voss, PhD, Department of Psychology, 2029 Sheridan Road, Northwestern University, Evanston, IL 60208-2710, USA. Email: joel-voss{at}northwestern.edu.
Familiarity refers to an explicit recognition experience without any necessary retrieval of specific detail related to the episode during which initial learning transpired. Prior experience can also implicitly influence subsequent processing through a memory phenomenon termed conceptual priming, which occurs without explicit awareness of recognition. Resolving current theoretical controversy on relationships between familiarity and conceptual priming requires a clarification of their neural substrates. Accordingly, we obtained functional magnetic resonance images in a novel paradigm for separately assessing neural correlates of familiarity and conceptual priming using famous and nonfamous faces. Conceptual priming, as shown by more accurate behavioral responses to strongly conceptually primed than to weakly conceptually primed faces, was associated with activity reductions in left prefrontal cortex, whereas familiarity was associated with activity enhancements in right parietal cortex for more-familiar compared with less-familiar faces. This neuroimaging evidence implicates separate neurocognitive processes operative in explicit stimulus recognition versus implicit conceptual priming.
Key Words: explicit memory • fMRI • functional magnetic resonance imaging • implicit memory • memory systems • neuroimaging