Effect of anodal transcranial direct current stimulation on balance in children with autism spectrum disorder

Abstract Background Autism spectrum disorder (ASD) is a neurodevelopmental delay condition. Although behavioural abnormalities are the primary indicators of the disorder, still a significant number of children with ASD present with motor abnormalities. Research has also identified deficiencies in their postural stability, and their gait patterns, which impaired their motor coordination. Transcranial direct current stimulation (tDCS) is a safe, accessible brain stimulation method, the impact of tDCS on the primary motor cortex during motor training, which demonstrated improvements in balance and motor skills in ASD children had been investigated. The present study seeks to examine the effect of anodal tDCS over the primary motor cortex on balance in patients with ASD. Results Both groups showed significant difference in MABC-2 balance subscale and QNST when baseline was compared to post-intervention and to the follow-up parameters. Both the post-intervention and follow-up balance subscale of MABC-2 and QNST were significantly higher in group I (who received tDCS sessions and neuro- rehabilitation programme) compared to group II (who received rehabilitation programme only). Similarly, the percentage of change from baseline to post-intervention and to 2-month follow-up of both MBC-2 balance subscale and QNST was significantly higher in group I in comparison to group II. In group I, there was a positive correlation between the Quick Neurological Screening Test (QNST) and both childhood autism rating scale (CARS) scores and Vineland scores. In group II, there was a negative correlation between the Movement Assessment Battery for Children-2 (MABC2) and CARS scores and a positive correlation between the MABC2 and Vineland. In both groups, there was a negative correlation between MABC2 SD and BMI. Conclusions tDCS is a non-invasive new adjuvant therapeutic approach in ASD. The current study revealed that severe autistic symptoms are associated with greater motor deficits. Immediately after applying tDCS sessions alongside neurorebilitation programme, balance subscales and neurological deficits improved significantly more than applying neurorebilitation programme alone and this effect continued in the follow- up.