Effects of Non-invasive Neurostimulation on Autism Spectrum Disorder: A Systematic Review

Area of Science:

• Neuroscience
• Psychiatry
• Neurology

Background:

• Autism spectrum disorder (ASD) is a neurodevelopmental condition marked by social communication impairments and repetitive behaviors.
• Noninvasive brain stimulation (NIBS) techniques, such as tDCS and TMS, are emerging as potential therapeutic interventions for neuropsychiatric disorders.

Purpose of the Study:

• To systematically review the therapeutic applications of tDCS and repetitive TMS (rTMS) in individuals with ASD.
• To evaluate the effects of NIBS on cognitive, behavioral, and biological dimensions in ASD patients.

Main Methods:

• A systematic literature search was conducted across major databases (Scopus, Web of Science, PubMed, Cochrane, Embase).
• 32 original articles on tDCS or rTMS for ASD treatment were screened and analyzed independently according to PRISMA guidelines.
• Studies included case reports, non-controlled trials, and controlled trials assessing NIBS effects.

Main Results:

• Existing evidence suggests NIBS may offer benefits for ASD symptoms, including repetitive behaviors, sociability, and executive functions.
• The review identified 8 tDCS reports, 23 rTMS reports, and 1 report combining both methods.
• Significant heterogeneity in data and potential publication bias were noted, necessitating cautious interpretation.

Conclusions:

• NIBS methods show promise as a therapeutic option for certain ASD dimensions.
• High-quality, randomized, double-blind, sham-controlled trials with adequate follow-up are crucial to establish the definitive efficacy of NIBS for ASD treatment.