Effects of Prefrontal tDCS on Brain Metabolites in the DLPFC of Healthy Subjects - a Double-Blind Placebo-controlled MRS Study

Abstract Background: Transcranial direct current stimulation (tDCS) is a non-invasive brain technique to change cortical excitability by transferring weak through the scalp. The clinical impact of prefrontal tDCS has been demonstrated in initial pilot studies, but underlying mechanism still not fully understood. Studies investigating neuronal excitation and inhibition dorsolateral cortex (DLPFC) using magnetic resonance spectroscopy (MRS) metabolites such as glutamate gamma-aminobutyric acid (GABA) have shown heterogeneous results. aim this double-blind, placebo-controlled study was investigate effects on glutamate, glutamine/glutamate (Glx), N-Acetylaspartate (NAA), GABA left DLPFC combined tDCS/MRS healthy participants. Thus, extends previous approach other target regions. Methods: Forty-one participants were recruited. Bifrontal, sham-controlled applied (anode: F3) right (cathode: F4) inside an MRI Siemens Prisma scanner neuroConn DC-Stimulator MR device. Active consisted 2mA electrical delivered for duration 20 minutes, while sham condition only ramp-up/ramp-down sequence induce tactile sensations. Three MEGA-PRESS sequences recorded before, during, after stimulation, well fMRI at baseline post-stimulation resting state condition. open-source software Gannet 3.1 used calculate tissue- alpha-corrected Glx concentrations. Glutamate NAA concentrations calculated via LCModel. Results: An analysis revealed no significant differences between active tDCS, however, results will be presented further discussed together with correction neurotransmitter concentration grey matter tissue MRS calculations. Research Category Technology Methods Basic Research: 9. Direct Current Stimulation Keywords: Magnetic Resonance (MRS), transcranial (tDCS),