FUNCTIONAL NEUROIMAGING STUDIES OF ENCODING, PRIMING, AND EXPLICIT MEMORY RETRIEVAL

Human functional neuroimaging techniques provide a powerful means of l inking neural level descriptions of brain function and cognition, The exploration of the functional anatomy underlying human memory comprise s a prime example, Three highly reliable findings linking memory-relat ed cognitive processes to brain activity are discussed, First, priming is accompanied by reductions in the amount of neural activation relat ive to naive or unprimed task performance, These reductions can be sho wn to be both anatomically and functionally specific and are found for both perceptual and conceptual task components, Second, verbal encodi ng, allowing subsequent conscious retrieval, is associated with activa tion of higher order brain regions including areas within the left inf erior and dorsal prefrontal cortex, These areas also are activated by working memory and effortful word generation tasks, suggesting that th ese tasks, often discussed as separable, might rely on interdependent processes, Finally, explicit (intentional) retrieval shares much of th e same functional anatomy as the encoding and word generation tasks bu t is associated with the recruitment of additional brain areas, includ ing the anterior prefrontal cortex (right > left), These findings illu strate how neuroimaging techniques can be used to study memory process es and can both complement and extend data derived through other means , More recently developed methods, such as event-related functional MR I, will continue this progress and may provide additional new directio ns for research.