Repetition of visually common objects was examined in relation to prior intentional learning and memory status using a delayed match-to-sample task in humans. Both response time and two temporally separate event-related potential (ERP) components indexed repetition. The early repetition effect (∼200-550 ms) evoked more ERP responses for repeated visual objects, and was diminished by prior intentional learning (old/new) or being maintained in working memory (targets/distracters). In contrast, the late repetition effect (after ∼550 ms) evoked reduced ERP activation for repeated items, and was not affected by prior learning or working memory status. Our source localization results indicate that the late and posterior repetition effect in visual cortex is consistent with repetition suppression results reported in monkey physiology and human fMRI studies. Meanwhile, the early and anterior repetition effect, in temporal pole and frontal cortices, is modulated by explicit memory mechanisms.
|Number of pages||13|
|State||Published - Nov 23 2007|
Bibliographical noteFunding Information:
The present study was supported by NIH grant AG00986, a pilot grant as part of NIH grant P50 AG05144-21 (Y.J.), Chinese Ministry of Education 20040028001, Beijing Key Laboratory PHR(IHLB), and National Natural Science Foundation of China 30170322 and 30570603 (C.G.). The authors thank Q. Zhang for assistance in data collection, and two anonymous reviewers for insightful suggestions.
- temporal pole
- working memory
ASJC Scopus subject areas
- Neuroscience (all)