Poster Session D, Monday, March 25, 8:00 – 10:00 am, Pacific Concourse
Behavioral and electrophysiological correlates of the memory search process during continuous recognition
John E. Scofield1, Mason H. Price2, Angelica Flores3, Edgar C. Merkle1, Jeffrey D. Johnson1; 1University of Missouri, 2University of Nebraska Medical Center, 3Universidad de las Américas Puebla
Studies employing either continuous recognition or judgments of recency have demonstrated that response times (RTs) increase sub-linearly with increasing cue-target lag, suggesting that memory search sometimes operates sequentially along a compressed timeline. Less is understood however about whether and how this thorough search process might be abandoned when memories increase in strength. Here, we tested such a situation by acquiring EEG during a continuous recognition task in which items were repeated up to three times and did so across a range of lags lasting from about five seconds to one minute. Analysis of the RTs and multivariate pattern analysis (MVPA) of the EEG data identified graded effects according to the repetition manipulation. Bayesian multilevel modeling also indicated that RTs increased in a logarithmic manner with increasing lag, supporting the notion of a backwards self-terminating search along a compressed representation of time. Moreover, modeling revealed interactions between lag and repetition for both the behavioral and neural measures. These results provide converging forms of evidence that the sequential search process can be rapidly abandoned, making way for alternative, and possibly threshold-based means of making recognition judgments. Together, the findings suggest that even simple tasks can reveal the rapid dynamics by which we switch between distinct forms of neurocognitive processes that support memory retrieval.
Topic Area: LONG-TERM MEMORY: Episodic