Targeting Repetitive Behaviors in Autism Spectrum Disorder Via Transcranial Direct Current Stimulation

Active cathodal HD-tDCS over pre-SMA cortex will be delivered for 10 days (3 sessions per week). The 4 × 1 montage using small circular electrodes (diameter 1 cm) will be applied with the cathode placed centrally over Fz. The current intensity will be set at 0.5 mA for a total of 20 minutes (30 s ramp up/down).

Active cathodal HD-tDCS over left DLPFC cortex will be delivered for 10 days (3 sessions per week). The 4 × 1 montage using small circular electrodes (diameter 1 cm) will be applied with the cathode placed centrally over F3. The current intensity will be set at 0.5 mA for a total of 20 minutes (30 s ramp up/down).

Sham HD-tDCS will be delivered over pre-SMA or left-dlPFC cortex for 10 days (3 sessions per week). The same electrodes placement as well as the stimulation set-up will be used as in the active stimulation conditions, but the current will be applied for 30 s and will be ramped down (0 mA) during the rest of the session without the participants awareness. Each Sham session will last 20 minutes.