Transcranial Direct Current Stimulation Modulates Working Memory Maintenance Processes in Healthy Individuals

Stevan Nikolin*, Donel Martin, Colleen K Loo, Tjeerd W. Boonstra

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

113 Downloads (Pure)

Abstract

BACKGROUND: The effects of transcranial direct current stimulation (tDCS) at the pFC are often investigated using cognitive paradigms, particularly working memory tasks. However, the neural basis for the neuromodulatory cognitive effects of tDCS, including which subprocesses are affected by stimulation, is not completely understood.

AIMS: We investigated the effects of tDCS on working memory task-related spectral activity during and after tDCS to gain better insights into the neurophysiological changes associated with stimulation.

METHODS: We reanalyzed data from 100 healthy participants grouped by allocation to receive either sham (0 mA, 0.016 mA, and 0.034 mA) or active (1 mA or 2 mA) stimulation during a 3-back task. EEG data were used to analyze event-related spectral power in frequency bands associated with working memory performance.

RESULTS: Frontal theta event-related synchronization (ERS) was significantly reduced post-tDCS in the active group. Participants receiving active tDCS had slower RTs following tDCS compared with sham, suggesting interference with practice effects associated with task repetition. Theta ERS was not significantly correlated with RTs or accuracy.

CONCLUSIONS: tDCS reduced frontal theta ERS poststimulation, suggesting a selective disruption to working memory cognitive control and maintenance processes. These findings suggest that tDCS selectively affects specific subprocesses during working memory, which may explain heterogenous behavioral effects.

Original languageEnglish
Pages (from-to)468-484
Number of pages17
JournalJournal of Cognitive Neuroscience
Volume35
Early online date28 Dec 2022
DOIs
Publication statusPublished - 1 Mar 2023

Cite this