Comparative Efficacy of QEEG-Guided rTMS and Home-Based tDCS for Social Communication and Behavioral Outcomes in Autism Spectrum Disorder: A Parallel Cohort Analysis

Abstract

Background: Autism Spectrum Disorder (ASD) is increasingly targeted with non-invasive neuromodulation, yet comparative evidence for the two most accessible approaches quantitative EEG guided repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) remains scarce.

Objective: To synthesise and directly contrast clinical efficacy, neurophysiological change and real-world feasibility of intensive clinic based rTMS versus home supervised tDCS, each delivered to the dorsolateral prefrontal cortex (DLPFC) in paediatric ASD.

Methods: Individual level pre/post data from two prospectively registered observational cohorts were re analysed. The rTMS study enrolled 56 children/ adolescents (mean age 9 y) who received 40 QEEG tailored sessions (1 Hz right + 10 Hz left DLPFC) over 4 weeks. The tDCS study involved 265 participants (3–18 y) completing twenty 1.5–1.8 mA anodal left DLPFC sessions across 4 weeks, administered at home under remote monitoring. Shared outcome instruments (SRS 2, ADOS 2, ABC, RBS R) were harmonised, and Hedges g was computed. Qualitative caregiver feedback on feasibility and acceptability was thematically integrated.

Results: rTMS produced large improvements across all domains (g = 1.00–1.55), with mean SRS 2 T scores decreasing by 11.2 points and ABC totals by 12.3 points. tDCS yielded moderate but significant gains in verbal (g = 0.52) and nonverbal (g = 0.48) social communication, emotional regulation (g = 0.57) and executive functions (g = 0.45). Neither modality incurred serious adverse events; transient scalp discomfort (rTMS) and mild skin irritation (tDCS) were the most common side effects. Caregivers valued the stronger behavioural impact of rTMS but favoured the logistical ease and lower cost of home based tDCS.

Conclusions: Both neuromodulation paradigms significantly ameliorate core ASD symptoms, with rTMS conferring larger effect sizes and tDCS offering superior scalability. A stepped care model initiating with portable tDCS and escalating to intensive QEEG guided rTMS for partial responders merits prospective randomised evaluation.

Autism Spectrum Disorder (ASD) is a heterogeneous neurodevelopmental condition currently affecting roughly 1 in 36 children aged eight years in the United States, with a male-to-female ratio of nearly 4:1 (cdc.gov). The DSM-5-TR defines ASD by two obligatory domains, the first of which is persistent deficits in social communication and social interaction across multiple contexts.