Poster A36, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C
Smoothing over the differences in working memory performance by tACS
Yuri G. Pavlov1,2, Nadezhda V. Pavlova1,2; 1University of Tuebingen, 2Ural Federal University
Despite the growing interest to the working memory (WM) in the last decades all existing neuroimaging studies have at least one limitation for investigation of individual differences in WM performance. In order to overcome these limitations, 156 subject were participating in solving highly demanding WM tasks which gave us the opportunity to distinguish EEG activity of individuals with different levels of WM performance. Additionally, using two types of tasks, which required either only retention of stimulus set or manipulation of content, we revealed EEG correlates of temporary storage and central executive components of WM and assessed their contribution to individual differences. The study showed striking individual differences in dynamics of frontal midline theta activity especially in the manipulation condition. Based on these results the second experiment was conducted. Twenty-two healthy adults participated in two testing sessions (after sham and transcranial alternating current stimulation (tACS)). tACS was applied for 20 min over Fpz and CPz at 6 Hz, 1 mA. No after-effects of tACS were observed in the stimulation sessions as compared to sham. The data suggest that tACS delivered before the WM task is not able to produce any observable changes in WM performance. Future studies could apply simultaneous stimulation and EEG recording during maintenance of information in WM for better understanding of the theta tACS effects.
Topic Area: EXECUTIVE PROCESSES: Working memory