Cathodal Transcranial Direct Current Stimulation to Ameliorate the Frequency and Severity of Motor Tics: A Case Study of Tourette Syndrome

Dysregulated neuronal activity in Cortico-Striato-Thalamo-Cortical (CSTC) networks is primarily described as the pathophysiology of Tourette Syndrome (TS). New neuromodulation techniques including noninvasive transcranial Electrical Stimulation (tES) are increasingly considered among potential therapeutic options for TS. To test the therapy protocol with transcranial Direct Current Stimulation (tDCS) a 31 year-old male patient with TS was selected to be administered for 10 sessions over five days of bilateral cathodal tDCS (30 minutes, 2 mA) on C3 and FC5, while the anode electrodes were placed on FP2. Tic severity and frequency were subjectively reported by the subject following the treatment on weekly basis and treatment response was objectively assessed by two experts. The patient noted that he was able to control his unwanted movement after over one year follow-up. The current study results together with earlier reports support the therapeutic effects of cathodal tDCS on tics in patients with TS. Randomized sham-controlled studies are required to shed more light on such therapeutic impact and the optimized protocols.