Enhancing Anger Perception With Transcranial Alternating Current Stimulation Induced Gamma Oscillations

Background: In recent years a variety of neuroimaging studies have highlighted a role of neural oscillations in perception and cognition. However, surprisingly little is known about oscillatory activity underlying facial emotion perception. The limited number of studies that have addressed this question indicate that gamma oscillations are one mechanism underlying this process. Objective: The present study aimed to further elucidate the role of neural oscillations within the gamma range in facial emotion perception in healthy adults by using transcranial alternating current stimulation (tACS). Methods: To that effect we carried out three experiments with separate groups of participants using tACS to modulate occipital oscillations while participants completed facial anger and facial identity tasks. Results: The results of these experiments indicated that modulating occipital gamma with 40 Hz tACS enhances facial anger perception. Conclusion: This finding implicates an important role of occipital gamma oscillations in facial emotion perception. (C) 2015 Elsevier Inc. All rights reserved.