A pilot study of alternative transcranial direct current stimulation electrode montages for the treatment of major depression

J Affect Disord. 2014;167:251-8. doi: 10.1016/j.jad.2014.06.022. Epub 2014 Jun 18.

Abstract

Background: Typically, transcranial direct current stimulation (tDCS) treatments for depression have used bifrontal montages with anodal (excitatory) stimulation targeting the left dorsolateral prefrontal cortex (DLPFC). There is limited research examining the effects of alternative electrode montages.

Objective/hypothesis: This pilot study aimed to examine the feasibility, tolerability and safety of two alternative electrode montages and provide preliminary data on efficacy. The montages, Fronto-Occipital (F-O) and Fronto-Cerebellar (F-C), were designed respectively to target midline brain structures and the cerebellum.

Methods: The anode was placed over the left supraorbital region and the cathode over the occipital and cerebellar region for the F-O and F-C montages respectively. Computational modelling was used to determine the electric fields produced in the brain regions of interest compared to a standard bifrontal montage. The two montages were evaluated in an open label study of depressed participants (N=14). Mood and neuropsychological functioning were assessed at baseline and after four weeks of tDCS.

Results: Computational modelling revealed that the novel montages resulted in greater activation in the anterior cingulate cortices and cerebellum than the bifrontal montage, while activation of the DLPFCs was higher for the bifrontal montage. After four weeks of tDCS, overall mood improvement rates of 43.8% and 15.9% were observed under the F-O and F-C conditions, respectively. No significant neuropsychological changes were found.

Limitations: The clinical pilot was open-label, without a control condition and computational modelling was based on one healthy participant.

Conclusions: Results found both montages safe and feasible. The F-O montage showed promising antidepressant potential.

Keywords: Computer simulation; Depression; Direct current; Stimulation; Therapy.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Affect
  • Antidepressive Agents / therapeutic use
  • Cerebellum*
  • Computer Simulation
  • Depressive Disorder, Major / diagnosis*
  • Depressive Disorder, Major / psychology
  • Depressive Disorder, Major / therapy*
  • Electrodes, Implanted* / adverse effects
  • Feasibility Studies
  • Female
  • Humans
  • Male
  • Middle Aged
  • Neuropsychological Tests
  • Occipital Lobe*
  • Pilot Projects
  • Prefrontal Cortex*
  • Transcranial Direct Current Stimulation* / instrumentation
  • Transcranial Direct Current Stimulation* / methods
  • Treatment Outcome

Substances

  • Antidepressive Agents