Transcranial direct current stimulation (tDCS) over right temporoparietal junction (rTPJ) for social cognition and social skills in adults with autism spectrum disorder (ASD).

Social deficits are core to autism spectrum disorder (ASD). Current treatments are extremely time- and labor-intensive. Transcranial direct current stimulation (tDCS) may be a promising treatment modality to safely enhance treatments targeting social cognition and social skills. This pilot study investigates the effectiveness of social skills treatment interventions paired with anodal tDCS for six adults 18-58 years with ASD. Differences were predicted on the verbal fluency (VF) test and a test of social skills (TASSK-M) for verum (2.0 mA) vs. sham tDCS, which was randomly assigned in a within-subjects, double-blinded design in adults with ASD with normal or higher cognitive functioning. The anode electrode was placed over right temporoparietal (CP6) and cathode over ipsilateral deltoid. Wilcoxon signed-rank tests for paired data indicated that participants received a significantly higher score on the VF test after receiving verum tDCS compared to sham tDCS, with no significant differences found on the TASSK-M. Post-hoc analysis showed that the emotion-word portion of the VF test, specifically, indicated significant differences when comparing verum to sham tDCS conditions. These findings provide optimism for the use of tDCS as delivered in the current study paired with social skills treatment interventions for ASD, particularly for improving skills of emotion verbal fluency.

Transcranial Direct Current Stimulation to the Right Temporoparietal Junction for Social Functioning in Autism Spectrum Disorder: A Case Report.

OBJECTIVES: While there is evidence of improved social functioning after applying transcranial direct current stimulation (tDCS) at the right temporoparietal junction (rTPJ) in individuals who are healthy, no current studies have investigated the use of tDCS at the rTPJ to improve social functioning in individuals with autism spectrum disorder (ASD). This case investigates the use of tDCS applied to the rTPJ to target social functioning in a high-functioning adult with ASD. METHODS: The authors present a case of an 18-year old patient with ASD treated successfully with tDCS; 1.5 mA of tDCS was applied once a day for 30 minutes for 8 consecutive days with the anode electrode over rTPJ (CP6 in the 10/10 electroencephalogram system) and the cathode electrode placed on the ipsilateral deltoid. Behavioral outcome was assessed using the Autism Treatment Evaluation Checklist prior to tDCS, after the final tDCS session, and at 2 months after tDCS. An additional, informal follow-up was also made 1 year after tDCS. RESULTS: Autism Treatment Evaluation Checklist showed substantial improvement in social functioning from baseline to post-tDCS, which was maintained at 2 months. The patient also reported lessened feelings of anger and frustration over social disappointments. Informal follow-up 1 year after stimulation indicates that the patient continues to maintain many improvements. CONCLUSIONS: Anodal tDCS to the rTPJ may represent an effective treatment for improving social functioning in ASD, with a larger clinical trial needed to validate this effect.