No Effects of Anodal tDCS on Local GABA and Glx Levels in the Left Posterior Superior Temporal Gyrus

Frontiers in Neurology

Jörg Assmus¹  Lars Ersland³  Renate Grüner⁴  Kenneth Hugdahl⁵  Kristiina Kompus⁷  Gerard E. Dwyer⁷  Alexander R. Craven⁷  Marco Hirnstein⁷ 

[1] Centre for Clinical Research, Haukeland University Hospital, Bergen, Norway;Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway;Department of Clinical Engineering, Haukeland University Hospital, Bergen, Norway;Department of Physics and Technology, University of Bergen, Bergen, Norway;Department of Radiology, Haukeland University Hospital, Bergen, Norway;Division of Psychiatry, Department of Clinical Medicine, Haukeland University Hospital, Bergen, Norway;NORMENT Centre of Excellence, Haukeland University Hospital, Bergen, Norway;

关键词: tDCS;    GABA;    Glultamate;    magnetic resonance spectroscopy;    MRS;   

DOI  :  10.3389/fneur.2018.01145

来源: DOAJ

【 摘 要 】

A number of studies investigating the biological effects of transcranial direct current stimulation (tDCS) using magnetic resonance spectroscopy (MRS) have found that it may affect local levels of γ-aminobutyric acid (GABA), glutamate and glutamine (commonly measured together as “Glx” in spectroscopy), and N-acetyl aspartate (NAA), however, these effects depend largely on the stimulation parameters used and the cortical area targeted. Given that different cortical areas may respond to stimulation in different ways, the purpose of this experiment was to assess the as yet unexplored biological effects of tDCS in the posterior superior temporal gyrus (pSTG), an area that has attracted some attention as a potential target for the treatment of auditory verbal hallucinations in schizophrenia patients. Biochemical changes were monitored using continuous, online MRS at a field strength of 3 Tesla. Performing intrascanner stimulation, with continuous spectroscopy before, during and after stimulation, permitted the assessment of acute effects of tDCS that would otherwise be lost when simply comparing pre- and post-stimulation differences. Twenty healthy participants underwent a repeated-measures experiment in which they received both active anodal and sham intrascanner stimulation in a stratified, randomized, double-blind experiment. No significant changes in GABA, Glx, or NAA levels were observed as a result of anodal stimulation, or between active and sham stimulation, suggesting that a single session of anodal tDCS to the pSTG may be less effective than in other cortical areas that have been similarly investigated.

【 授权许可】

Unknown