Transcranial electrical stimulation of the occipital cortex during visual perception modifies the magnitude of BOLD activity: a combined tES-fMRI approach.

Neuroimage. 2015 Nov 19;

Authors: Alekseichuk I, Diers K, Paulus W, Antal A

Abstract
The aim of this study was to investigate if the blood-oxygenation-level-dependent (BOLD) changes in the visual cortex can be used as biomarkers reflecting the online and offline effects of transcranial electrical stimulation (tES). Anodal transcranial direct current stimulation (tDCS) and 10 Hz transcranial alternating current stimulation (tACS) were applied for 10 min duration over the occipital cortex of healthy adults during the presentation of different visual stimuli, using a crossover, double-blinded design. Control experiments were also performed, in which sham stimulation as well as another electrode-montage were used. Anodal tDCS over the visual cortex induced a small, but significant further increase in BOLD response evoked by a visual stimulus, however no after-effect was observed. 10 Hz tACS did not result in an online effect, but a widespread offline BOLD decrease over the occipital, temporal and frontal areas. These findings demonstrate that tES during visual perception affects the neuronal metabolism, which can be detected with functional magnetic resonance imaging (fMRI).

PMID: 26608246 [PubMed - as supplied by publisher]