Modulating Plasticity in the Motor Cortex Using Repetitive Transcranial Magnetic Stimulation to Improve Motor Function in Autism Spectrum Disorder
In the current project, investigators have two main goals: i) Testing whether an excessive plasticity, i.e. hyperplasticity in the motor cortex underlies motor function difficulties in autistic adults, and ii) Using repetitive Transcranial Magnetic Stimulation (rTMS) with autistic adults to examine whether resulting reduced hyperplasticity in the motor cortex will be associated with clinical improvements in the motor function.
⁃ ASD or control participants must meet all of the inclusion criteria to eligible for this study:
• Aged between 18 and 40 years old. 40 years is chosen as the cut-off because of the report of high rates of Parkinsonism in autistic adults \> 39years;
• Have IQ\>70;
• Are able to read, write and communicate effectively in English;
• Are able to provide informed consent. We will recruit only intellectually-able autistic adults. The intellectual ability will be determined using WASI-II. The ability to provide consent will be determined using clinical assessment.
• Have no prior history of seizure;
• Must sign and date the informed consent form;
• Stated willingness to comply with all study procedures;
• Agreement to adhere to Lifestyle Considerations, that is: refrain from consumption of alcohol, tobacco, marijuana, or caffeine on the day of study visits.
⁃ All ASD participants:
• Will have DSM-5 diagnosis of ASD without intellectual disability, confirmed by clinical assessment and the Autism Diagnostic Observation Schedule - 2 (ADOS-2);
• Will have significant motor function difficulties defined as a standard composite score \<40 (i.e., \>1 standard deviation below the mean) on either fine or gross motor composite scores of the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition or BOT-2;
• Are clinically stable as determined by clinical assessment, with no medication changes over the past 4 weeks. Given the high variability of handedness in ASD, we will include participants with left, right or mixed handedness.