Incidental learning enhances auditory signal detection

Poster Session B - Sunday, April 14, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Manda Fischer¹³ (mfisch5@uwo.ca), Morris Moscovitch¹², Claude Alain¹²; ¹University of Toronto, ²Rotman Research Institute at Baycrest Hospital, ³University of Western Ontario

Incidental memory can bias attention to enhance perception at retrieval. We tested the hypothesis that both the degree of neural instantiation at learning and explicit memory at retrieval facilitate signal detection. First, participants listened to everyday sounds (e.g., cityscape soundscape) either played alone (neutral-cue) or paired with a lateralized suprathreshold target tone (memory-cue). To track learning-related changes, we measured the acoustic change complex (ACC), using high-density electroencephalography (EEG). At test, every soundscape contained a lateralized tone that was very faint. Memory-cue trials were paired with a faint tone that appeared on the same side as it did during learning, while neutral-cue trials were paired with a tone that appeared on a pseudo-random side. Participants detected the faint tone as quickly as possible and indicated whether they had an explicit memory for each soundscape. Reaction time for detecting the target tone was faster for memory-trials compared to neutral ones. Detection accuracy for memory-cue trials was associated with greater ACC amplitudes, suggesting that greater sensitivity to acoustic changes at the level of the auditory cortex at learning may facilitate associative memory encoding for later use at test. Further, detection was related to explicit memory for the soundscape. Together, larger ACC amplitudes may enhance associative memory formation at encoding, while explicit memory for the soundscape may support general processing efficiency to aid target detection at retrieval. These results refine our model of memory-biased perception by demonstrating that incidental exposure to soundscapes can produce associative representations robust enough to enhance perception.

Topic Area: LONG-TERM MEMORY: Episodic