Longitudinal Neurofunctional Stabilization Following Prolonged Neuromodulation in a Child With Autism Spectrum Disorder: A Single-Case Observational Study

This preprint reports a longitudinal single-case observational study describing neurofunctional changes temporally associated with prolonged neuromodulation in a child diagnosed with Autism Spectrum Disorder (ASD). The subject, a 9-year-old child with a history of early developmental adversity and limited functional progress despite years of conventional educational and behavioral interventions, was followed over an extended period during which neuromodulation was introduced as a complementary approach. Observations were collected longitudinally while the educational and therapeutic context remained stable. The report focuses on changes in neurofunctional domains including sensory regulation, behavioral stability, attentional availability, emotional regulation, and social engagement. Language outcomes were intentionally excluded. The manuscript documents a cumulative volume of neuromodulation exposure that, to our knowledge, has not previously been reported in the pediatric ASD literature. This work does not claim causality or therapeutic efficacy. Rather, it provides a detailed descriptive account of a single developmental trajectory, highlighting the potential relevance of cumulative exposure and timing in neuromodulation-based approaches. The findings are intended to support further systematic investigation and controlled studies in this area. This manuscript is a preprint and has not yet undergone peer review.