Selective Modulation of Interhemispheric Functional Connectivity by HD-tACS Shapes Perception

• DOI: 10.1371/journal.pbio.1002031
• Publication Date: 2014-12-30T18:49:06Z
• Authors: Randolph F. Helfrich; Hannah Knepper; Guido Nolte; Daniel Strüber; Stefan Rach; Christoph S. Herr...; Till R. Schneider; Andreas K. Engel
• Keywords: Entrainment (biomusicology); Phase synchronization

Oscillatory neuronal synchronization between cortical areas has been suggested to constitute a flexible mechanism coordinate information flow in the human cerebral cortex. However, it remains unclear whether synchronized activity merely represents an epiphenomenon or is causally involved selective gating of information. Here, we combined bilateral high-density transcranial alternating current stimulation (HD-tACS) at 40 Hz with simultaneous electroencephalographic (EEG) recordings study immediate electrophysiological effects during entrainment oscillatory gamma-band signatures. We found that interhemispheric functional connectivity was modulated predictable, phase-specific way: In-phase enhanced synchronization, anti-phase impaired coupling. Perceptual correlates these changes were ambiguous motion task, which strongly support relevance long-range Additionally, our results revealed decrease alpha power response gamma band This finding provides causal evidence for antagonistic role and oscillations parieto-occipital cortex confirms observed modulations physiological nature. Our demonstrate network across several spatiotemporal scales essential conscious perception cognition.