Presentation
Search Abstracts | Symposia | Slide Sessions | Poster Sessions | Lightning Talks
That rings a bell! How semantic memory strength incrementally promotes a ‘feeling of knowing’ during spoken language processing
Poster B16 in Poster Session B, Tuesday, October 24, 3:30 - 5:15 pm CEST, Espace Vieux-Port
HAINING CUI1, XIAOMING JIANG1,2, MARC D. PELL1; 1McGill UNIVERSITY, 2SHANGHAI INTERNATIONAL STUDIES UNIVERSITY
In daily communication, we rely on semantic memory to access existing factual knowledge about the world, and to distinguish true information from false, in order to build mental representations of knowing and to form beliefs when judging another person's verbal statement. Neurophysiological studies have examined the neurocognitive mechanisms that allow listeners to achieve a feeling of knowing (FOK) based on various linguistic and socio-perceptual cues during language processing (e.g., Jiang & Pell, 2016; Paynter et al., 2009); however, few have considered how internal cues, such as the strength of long-term memory for factual knowledge, affect incremental processes for establishing a mental state of knowing or believing. In this study, we presented pre-recorded, validated statements of world knowledge produced in a neutral tone of voice which varied in truth value (true, false) and memory accessibility (strong, weak). Utterances were rated by 33 healthy English speakers who evaluated how much “the speaker knows what they are talking about” on a 5-pt scale while their EEG was recorded. Statements were: a) true general world facts with strong shared memory strength among listeners and speakers (e.g., a LAMB is a young | SHEEP…); b) false statements widely known to be incongruent with world knowledge (strong memory strength, e.g., a COLT is a young | SHEEP…); c) true but lowly known statements (weak memory strength) with the same critical word (HOGGET is meat from a | SHEEP…); and d) false lowly known facts with weak memory strength (VENISON is meat from a | SHEEP…). Event-related potentials time-locked to the critical word onset (“SHEEP”) revealed significant graded differences in the N400 time window (300-600ms) at central-parietal electrodes across all four conditions of truth value and memory strength: the N400 amplitude was greatest for false statements with weak memory strength, followed by true statements with weak memory strength, false statements with strong memory strength, and was most reduced for well-known true statements with strong memory strength. The interactive effect of memory accessibility and truth value on the N400 was followed by a broadly distributed late positive component (LPC, peaking at 867ms) which generally increased for statements with strong vs. weak memory strength. Graded differences observed in the N400 suggest that this component indexes both memory and contextual cue-based expectations and ease of semantic access mechanisms, which may be actively used by comprehenders as efficient semantic processing strategies depending on task demands. The selective impact of semantic accessibility on the LPC response could reflect an early stage of “feeling of knowing” elaboration, promoting a subjective feeling of high level of certainty and detailed memory recollection success. Taken together, our findings provide new details on how overall memory strength plays a key role in semantic memory access, recollection and feeling of knowing attributions during spoken language processing.
Topic Areas: Meaning: Discourse and Pragmatics, Meaning: Lexical Semantics