Adjunctive cerebellar anodal transcranial direct current stimulation for tardive dyskinesia in patients with...

Tardive dyskinesia (TD) remain a significant therapeutic challenge due to limited effective treatment options. Current framework implicates dysfunction of the cerebellar-basal ganglia-cortical network in hyperkinetic movement disorders. Cerebellar anodal transcranial direct current stimulation (a-tDCS) has shown promise in modulating motor circuits in movement disorders, but evidence in TD remains sparse.

This open-label pilot study included twelve adults with schizophrenia receiving stable antipsychotic treatment and clinically significant TD (Abnormal Involuntary Movements Scale [AIMS] score ≥5). Participants received five consecutive daily sessions of cerebellar a-tDCS (2 mA, 20 min/session), with the anode placed over the cerebellum (Iz) and the cathode over the right supraorbital region (Fp2). AIMS assessments were conducted at baseline (Day 1), post-intervention (Day 5) and follow-up (Day 30). Changes in AIMS scores were analysed using the Friedman test with post-hoc Durbin-Conover pairwise comparisons.

There was a significant reduction in total AIMS scores across time points (χ² = 17.4, df = 2, p < 0.001). Significant improvements were observed from baseline to Day 5 and baseline to Day 30 (both p < 0.001), with no significant difference between Day 5 and Day 30. Domain-wise analysis indicated the greatest improvement in orofacial dyskinesia. The intervention was well tolerated, with only mild, transient scalp sensations reported.

Adjunctive cerebellar a-tDCS was associated with a sustained reduction in TD and demonstrated good tolerability.