Neuromodulation Therapy Integrating Prefrontal rTMS and Neurofeedback for the Treatment of Autism
Objectives: The overall aim of the study was to investigate behavioral responses, ERP indices of information processing, and coherence of induced gamma oscillations in children with autism enrolled either in 18 weekly sessions of combined rTMS -NFB training group or in the wait-list group. The goal of our study was to investigate whether behavioral, EER and EEG indices, and behavioral evaluation outcomes will show positive changes in the treatment group (N=20) as compared to wait-list group (N=22).
Methods: We used 18 weekly sessions of 0.5 Hz rTMS bilaterally over dorsolateral prefrontal cortex followed by prefrontal neurofeedback in 20 children with autism (14.9 yrs). Another group of children with autism (N=22, 15.6 yrs) was tested twice within 4 months. Baseline and post-treatment assessments used selective attention tests with EEG/ERP recording and behavioral evaluations (Aberrant Behavior Checklist [ABC] and Repetitive Behavior Checklist [RBS-R]).
Results: Post-TMS-NFB evaluations showed decreased irritability and hyperactivity on ABC, and decreased stereotypic and total repetitive behaviors scores on RBS. The TMS-NFB group showed decrease of error rate (F=5.62, p=0.02). Magnitude of the frontal N100 decreased, while amplitude of the P200 to target stimuli increased post-TMS-NFB. Similar effects were expressed as well in the parietal P3b. The treatment group showed increase coherence of induced gamma to targets between frontal and temporal sites (e.g., F3-T7, F=6.67, p=0.014). NFB sessions resulted in linear regression of the theta-to-beta ratio and increase of gamma power over 18 sessions of integrated treatment.
Conclusions: Improved clinical behavioral evaluation outcomes along with functional EEG/ERP measures post-TMS-NFB are indicative of more efficient information processing post-treatment. The study represents a pilot translational clinical research exploration where rTMS and neurofeedback were combined, and treatment effects were compared with a wait-list group using clinical, behavioral and cognitive outcome measures. Preliminary results are very encouraging and warrant further more rigorous randomized controlled clinical trials.
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Sokhadze, E. M. et al. (2014) rTMS neuromodulation improves electrocortical functional measures of information processing and behavior in autism. Frontiers Systems Neuroscience. 8:134
Wang, Y., et al (2014) Prefrontal neurofeedback training approaches in autism. NeuroRegulation 1:275-277.