Poster Session E, Monday, March 25, 2:30 – 4:30 pm, Pacific Concourse
Fronto-Visual Dynamic Functional Connectivity during a Selective Attention Task is Modulated by Prefrontal High-Definition Transcranial Direct Current Stimulation
Rachel Spooner1, Michael Rezich1, Boman Groff1, Tony Wilson1; 1University of Nebraska Medical Center
Studies of visual attention have implicated theta, alpha, and gamma activity in the temporal recognition, protection, and organization of attended representations in visual cortices. In addition, studies have shown that higher-order regions such as the prefrontal cortex are critical to attentional processing, but far less is understood regarding laterality differences in attentional processing in the prefrontal cortices. To this end, we examined the impact of applying high-definition transcranial direct-current stimulation (HD-tDCS) to the left or right dorsolateral prefrontal cortex (DLPFC) on subsequent attentional processing. We predicted that HD-tDCS of the left versus right prefrontal cortex would differentially modulate performance on a visual selective attention task, and alter the oscillatory activity serving such cognitive processes. Our repeated-measures design included 25 healthy adults that underwent three separate sessions of HD-tDCS (sham, active left-, and active right-DLPFC) for 20 minutes. Following HD-tDCS, participants completed an attention paradigm during magnetoencephalography (MEG). The resulting oscillatory responses were imaged in the time-frequency domain using beamforming, and peak task-related neural activity was subjected to dynamic functional connectivity analyses to evaluate the impact of stimulation site (i.e., left and right DLPFC) on neural interactions. Our results indicated that HD-tDCS over the right DLPFC differentially modulated fronto-visual functional connectivity within distinct oscillatory rhythms compared to HD-tDCS of the left DLPFC and sham. Further, these tDCS-induced alterations in fronto-visual connectivity were uniquely related to behavioral performance on the Flanker task. These findings provide insight into the effects of HD-tDCS on the complex oscillatory mechanisms serving visual selective attention.
Topic Area: ATTENTION: Other