Exploring the Influence of Left Dorsolateral Prefrontal Cortex Intermittent Theta-Burst Stimulation on Working Memory Load: An EEG Study in Healthy Participants

Abstract

Aims: Working memory (WM), a short-term cognitive process involving the prefrontal cortex, is critical for daily functioning. This study investigated the effects of iTBS on WM performance and its neural mechanisms in healthy adults. Methods: Thirty-one healthy adults completed 1-back and 2-back tasks while undergoing EEG recording. Each received both active and sham iTBS over the left dorsolateral prefrontal cortex separately. Behavioral performance, EEG power, and functional connectivity were analyzed. Results: Active iTBS significantly increased theta power in prefrontal cortices during the 1-back task. It also enhanced alpha band connectivity between the left prefrontal and right parietal cortices. In the 2-back task, iTBS increased beta band connectivity between the right prefrontal and right parietal cortices, and alpha band connectivity between the left and right parietal cortices. No significant behavioral differences were found. Conclusion: These findings suggest that iTBS effects on WM are primarily reflected in large-scale oscillatory network dynamics, rather than solely in localized cortical activity or behavioral performance.