Effects of Theta Transcranial Alternating Current Stimulation Over the Frontal Cortex on Reversal Learning

Brain Stimul. Sep-Oct 2016;9(5):705-711. doi: 10.1016/j.brs.2016.04.011. Epub 2016 Apr 14.


Background: Theta oscillations in the electroencephalogram (EEG) are associated with learning and behavioral adaptation.

Objective: To investigate the effects of theta transcranial alternating current stimulation (tACS) applied to the frontal cortex on reversal learning.

Methods: Healthy volunteers participated in a sham-controlled between subjects design. TACS at 1 mA peak-to-peak was administered during a reward-punishment reversal learning task. Resting state EEG was measured before and after tACS and the task.

Results: Active tACS improved learning ability, but at the same time interfered with applying the rule to optimize behavior. Furthermore, a significant decrease in frontal theta-beta EEG ratios was observed following active tACS.

Conclusions: Results provide behavioral and electrophysiological evidence for influencing reversal learning with exogenous oscillatory electric field potentials applied to the frontal cortex.

Keywords: Electroencephalogram; Reversal learning; Theta activity; Theta–beta ratio; Transcranial alternating current stimulation.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Adult
  • Double-Blind Method
  • Electroencephalography
  • Female
  • Frontal Lobe / physiology*
  • Humans
  • Male
  • Reversal Learning / physiology*
  • Theta Rhythm / physiology*
  • Transcranial Direct Current Stimulation*
  • Young Adult