Effects of left ventrolateral prefrontal stimulation on forming and maintaining deep and shallow episodic traces

Peng, Nan; Wu, Wei; Della Sala, Sergio; Hoffman, Paul

Abstract

The levels-of-processing framework, proposing that deep encoding enhances retention, plays a crucial role in episodic memory research. Neuroimaging evidence highlights that increased activity of the left ventrolateral prefrontal cortex during deep encoding predicts subsequent memory success. However, cognitive mechanisms underlying this region's involvement in establishing and consolidating deep and shallow traces remain unclear. In this preregistered study, we investigated whether repetitive transcranial magnetic stimulation over the left ventrolateral prefrontal cortex versus the vertex differentially modulates the formation and maintenance of deep and shallow traces. Trains of 20 Hz online repetitive transcranial magnetic stimulation were delivered over the left ventrolateral prefrontal cortex or vertex during tasks involving pleasantness (deep) and alphabetical order (shallow) judgments of words. Following encoding, two recognition tests assessed immediate and 24-h delayed recognition of words. Compared to the vertex control, ventrolateral prefrontal stimulation selectively disrupted the formation of episodic memory under deep encoding conditions, evidenced by increased response time at encoding and reduced immediate recognition in the deep but not shallow condition. Notably, forgetting rates across the 24-h delay were similar for disrupted deep, intact deep, and shallow items, implying that the rate of trace decay is independent of the strength of trace formation. The constant trace decay indicates that distinct mechanisms are involved in establishing and maintaining episodic traces.

Citation

Peng, N., Wu, W., Della Sala, S., & Hoffman, P. (2024). Effects of left ventrolateral prefrontal stimulation on forming and maintaining deep and shallow episodic traces. Cerebral Cortex, 34(11), Article bhae437. https://doi.org/10.1093/cercor/bhae437

• Journal Article Type: Article
• Acceptance Date: Oct 17, 2024
• Online Publication Date: Nov 6, 2024
• Publication Date: Nov 1, 2024
• Deposit Date: Nov 6, 2024
• Publicly Available Date: Nov 7, 2024
• Print ISSN: 1047-3211
• Electronic ISSN: 1460-2199
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 34
• Issue: 11
• Article Number: bhae437
• DOI: https://doi.org/10.1093/cercor/bhae437
• Keywords: Recognition, rTMS, Episodic memory, prefrontal cortex, Levels Of Processing, Prefrontal Cortex, Humans, Reaction Time, Adolescent, Adult, Female, Male, Transcranial Magnetic Stimulation, Functional Laterality, Young Adult, Memory, Episodic, Recognition, P
• Public URL: https://durham-repository.worktribe.com/output/3083794
• PMID: 39503243