Does the longer application of anodal-transcranial direct current stimulaton increase corticomotor excitability further? A pilot study

Shapour Jaberzadeh, Andisheh Bastani Jahromi, Dawson Kidgell

Research output: Contribution to journalArticleResearchpeer-review


Introduction: Anodal transcranial direct current stimulation (a-tDCS) of the primary motor cortex (M1) has been shown to be effective in increasing corticomotor excitability.
Methods: We investigated whether longer applications of a-tDCS coincide with greater increases in corticomotor excitability compared to shorter application of a-tDCS. Ten right-handed healthy participants received one session of a-tDCS (1mA current) with shorter (10 min) and longer (10+10 min) stimulation durations applied to the left M1 of extensor carpi radialis muscle (ECR). Corticomotor excitability following application of a-tDCS was assessed at rest with transcranial magnetic stimulation (TMS) elicited motor evoked potentials (MEP) and compared with baseline data for each participant.
Results: MEP amplitudes were increased following 10 min of a-tDCS by 67% (p = 0.001) with a further increase (32%) after the second 10 min of a-tDCS (p = 0.005). MEP amplitudes remained elevated at 15 min post stimulation compared to baseline values by 65% (p = 0.02).
Discussion: The results demonstrate that longer application of a-tDCS within the recommended safety limits, increases corticomotor excitability with after effects of up to 15 minutes post stimulation.
Original languageEnglish
Pages (from-to)28-35
Number of pages8
JournalBasic and Clinical Neuroscience
Issue number4
Publication statusPublished - 2012


  • transcranial Direct Current Stimulation (tDCS)
  • transcranial Magnetic Stimulation (TMS)
  • Corticomotor Excitability

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