[Show abstract][Hide abstract] ABSTRACT: Background
False memory often involves retrieving events from the distant past that did not actually happen. However, recent evidence obtained using the Deese/Roediger-McDermott (DRM) paradigm for eliciting false memory experiences suggests that individuals can falsely believe that events occurred mere seconds in the past when they in fact did not. Subjects in these experiments endorsed unstudied critical lure words as having been studied, despite the fact that word lists were studied just moments before. We identified event-related brain potential (ERP) correlates of this experience, and included a repetition priming manipulation to better assess the functional significance of these ERPs.
Behavioral and ERP data were collected from 21 Capital Normal University students using a short-term DRM task.
Two categories of effects were identified that distinguished true from false short-term memory: (1) early semantic priming effects from 300 to 500 ms and (2) later retrieval and retrieval-monitoring effects after 500 ms. The repetition priming manipulation had distinct influences on these effects, consistent with their differential associations with semantic priming versus episodic retrieval.
Characterization of ERPs related to semantic priming and episodic retrieval provides important information regarding the mechanisms of short-term false memory. In contrast, most studies examining false memory in standard long-delay DRM paradigms identify ERP effects related only to retrieval monitoring. These findings highlight the neural processing involved in illusions of memory after very brief delays and highlight the role of semantic processing in short-term false memory.
[Show abstract][Hide abstract] ABSTRACT: An event-related potential study was conducted to make clear that how picture-word delayed matching encoding affects upon episodic retrieval, and to further investigate the relationship between encoding and episodic retrieval by ERP source analysis using the LORATA method (low resolution electromagnetic tomography, via Curry V6.0). The experiment used learning and recognition paradigm. The results showed that the identical matching encoding facilitated episodic retrieval, and there was extra activation of Lingual gyrus in the identical match old condition in ERP source analysis, whereas the categorical matching and non-match conditions showed similar mechanisms. Casting back to the encoding processing, it was shown that in the identical match condition an early P300 component from 350 to 450ms was evoked. Our results suggest that the early P300 component evoked by the picture-word identical matching is the critical factor affecting episodic retrieval.