Non-Invasive Brain Stimulation for motor improvement of children with Autism Spectrum Disorder

INTERVENTION: A randomized, placebo‐controlled, double‐blind clinical trial. Randomization will be performed using a program capable of generating random numbers to assign participants to one of the three study interventions. Randomization will be carried out considering the stratification according to the severity of the autism spectrum disorder, according to the Childhood Autism Classification Scale (CARS‐BR). For each stratum (mild, moderate and severe) the randomization sequence will be generated with the distributions properly organized and sealed in sequentially numbered opaque envelopes. Experimental group 1: 10 children with autism spectrum disorder. Ten sessions of motor training (treadmill training and circuit balance training) and anodic transcranial direct current stimulation over the primary motor cortex. Experimental group 2: 10 children with autism spectrum disorder. Ten sessions of motor training (treadmill training and circuit balance training) and anodic transcranial direct current stimulation over the cerebellum. Control group: 10 children with autism spectrum disorder. Ten sessions of motor training (treadmill training and circuit balance training) and placebo transcranial direct current stimulation. E02.331.750 CONDITION: Autism Spectrum Disorder F03.625 PRIMARY OUTCOME: Gross and fine motor skills assessed by the Movement Assessment Battery for Children‐2 (percentile) applied one week before and one, four and eight weeks after the end of the intervention. It is expected to find an increase in the percentile of the assessment scale, demonstrating improvement in motor skills, with a greater effect size for groups receiving active transcranial direct current stimulation compared to placebo transcranial direct current stimulation. INCLUSION CRITERIA: Diagnosis of autism spectrum disorder; classified as levels I, II and III according to the Diagnostic and Statistical Manual of Mental Disorders (DSM‐V); age between three and eight years; comprehension of simple verbal commands; no medication changes at least si Xmonths before the beginning of the study and during its performance; statement of informed consent signed by a legal guardian and statement of informed assent signed by the participant SECONDARY OUTCOME: Adverse effects assessed using a standardized questionnaire that quantifies the perception and intensity of symptoms. Assessments performed before and after each of the ten intervention sessions. It is expected not to find moderate or severe adverse effects during the intervention period. Characteristics of autistic behavior evaluated by the Childhood Autism Rating Scale which is an observation scale that will be applied with the person responsible for the participant. The scale will be applied one week before and four and eight weeks after the end of the intervention. It is expected to find a reduction in the severity of autistic symptoms observed by those responsible for the child after the interventions. Functional balance assessed by the Pediatric Balance Scale (points) applied one week before and one, four and eight weeks after the end of the intervention. It is expected to find an increase in the total score of the scale, demonstrating an improvement in functional balance, with a greater effect size for groups receiving active transcranial direct current stimulation compared to placebo transcranial direct current stimulation. Mobility and functional balance assessed by the execution time of the timed up and go test (seconds) performed one week before and one, four and eight weeks after the end of the intervention. It is expected to find a decrease in the test execution time after the interventions. Motor evoked potential amplitude (microvolts) assessed by transcranial magnetic stimulation synchronized with the electromyograph. Assessments performed one week before and one, four and eight weeks after the end of the intervention. It is expected to find an increase in motor evoked potential amplitude only after the intervention with active transcranial direct current stimulation. Social behavior, communication and general actions evaluated by the Autism Diagnostic Observation Schedule which is a questionnaire that will be carried out with the professional responsible for the participant's treatment. The questionnaire will be carried out one week before and four and eight weeks after the end of the intervention. It is expected to find a reduction in autistic symptoms observed by professionals after interventions. Time and space parameters of gate evaluated by the walk test (m/s) performed one week before and one, four and eight weeks after the end of the intervention. It is expected to find an increase in gait speed to perform the test after the interventions.