Poster D71, Monday, March 26, 8:00-10:00 am, Exhibit Hall C
Late positive event-related potential tracks outcome of cumulative memory judgments
Haopei Yang1,4, Ken McRae1,4, Stefan Köhler1,2,4,3; 1The Brain and Mind Institute, 2Rotman Institute of Philosophy, 3Rotman Research Institute, Baycrest Centre, 4Western University
Numerous studies have shown that the Late Positive Complex in event-related potentials (ERPs) tracks perceived item status in recognition-memory judgments. Recent findings suggest that it may reflect evidence accumulation relevant to the memory decision at hand. Extant research has primarily probed this ERP component with tasks that require judging whether an item was presented in a recent study phase. It is currently unclear whether the LPC also tracks response outcome in other types of memory judgments. Behavioral findings suggest that humans can accurately judge frequency of recent laboratory exposure and their cumulative lifetime experience with object concepts. The latter types of judgment display considerable consistency in a given culture, and are also known to have some external validity. In the current study, we asked whether the LPC tracks judgements about cumulative prior experience in a task-relevant manner. Participants were asked to perform cumulative memory judgements on concrete concepts selected from a normative database in two different memory tasks. One task required frequency judgements of exposure in an experimental study phase. The other task involved judgements of cumulative lifetime experience with object concepts. The LPC amplitude tracked judgement outcome in both tasks. By contrast, it was not sensitive to frequency of exposure in the study phase when no memory judgements were required. Moreover, it did not track normative ratings of lifetime exposure during frequency judgements of presentations at study. These findings suggest that the LPC tracks signals relevant to the outcome of the memory judgment at hand, beyond classic old-new responses.
Topic Area: LONG-TERM MEMORY: Episodic