Poster A126, Saturday, March 25, 5:00 – 7:00 pm, Pacific Concourse
Using ERPs to Dissociate the Neurocognitive Processes Underlying Knowledge Extension through Memory Integration in Adults
Nicole L. Varga1, Patricia J. Bauer1; 1Emory University
To build a general knowledge base, it is imperative that individuals acquire, integrate, and further extend knowledge across experiences. For instance, in one episode an individual may learn that George Washington was the first president. In a separate episode s/he may then learn that Washington was the commander of the Continental Army. Integration of the information in memory may then support self-derivation of the new knowledge that the leader of the Continental Army was also the first president. Despite a considerable amount of fMRI research aimed at further elucidating the neuroanatomical regions supporting this ability, a consensus has yet to be reached with regards to the precise neurocognitive processes involved. In the present research, we capitalized on the high temporal resolution of event-related potentials (ERPs) to isolate the distinct processes associated with successful integration and further extension of new factual knowledge. Adults read novel, related stem facts and were tested for self-derivation of novel integration facts while ERPs were recorded. Consistent with current theoretical models, three temporally-staged processes were implicated during integration of a second, related fact: (1) detection of a deviation between newly and previously learned information, (2) interpretation of the mismatch, and (3) binding of the relation in memory. During the test for self-derivation, a single ERP was elicited, which presumably reflected recombination of previously integrated knowledge. Together, the present research provides an understanding of the time-course of neural processing associated with the formation of a knowledge base, as well as insight into the cognitive functions involved.
Topic Area: LONG-TERM MEMORY: Semantic