Cerebellum and Autism: Regional Specialization for Social and Executive Functions

Not Applicable

Recruiting

• Conditions: Autism; Autism Spectrum Disorder
• Interventions: Device: Transcranial direct current stimulation

• Registration Number: NCT05396352
• Lead Sponsor: American University

Brief Summary

The goal of this study is to determine the impact of neuromodulation to the cerebellum on social and executive functions in neurotypical young adults and young adults with autism.

Detailed Description

Autism spectrum disorder is a prevalent neurodevelopmental condition characterized by deficits in social communication and the presence of repetitive and inflexible behaviors. There are currently few biologically-targeted treatment options for autism, in part because the underlying neurobiology is not well understood. One region of the brain that is consistently implicated in autism is the cerebellum. Specifically, two cerebellar subregions show structural and functional differences in autism: right cerebellar lobule VII (RVII) and the posterior cerebellar vermis. Based on the different anatomical connectivity of these regions, the investigators hypothesize that RVII and the posterior vermis regulate different core deficits in autism. In this study, the investigators combine cerebellar neuromodulation with functional neuroimaging to test the hypothesis that neuromodulation targeting RVII will selectively alter social learning and neural networks supporting social behavior, while neuromodulation targeting the posterior vermis will impact cognitive flexibility and neural networks involved in the allocation of attention. Neurotypical adults and adults with autism will complete social and cognitive flexibility tasks after excitatory, inhibitory, or sham neuromodulation in a within-subjects design. Some participants will receive neuromodulation targeting RVII and others will receive neuromodulation targeting the posterior vermis. The investigators will acquire functional brain imaging data during and after cerebellar neuromodulation, which will allow the team to better understand the mechanisms by which non-invasive neuromodulation might impact behavior in clinical disorders.

Study Timeline

• Study Start: 2022-01-01
• Study First Submitted: 2022-05-25
• Study First Submitted QC: 2022-05-25
• Study First Posted: 2022-05-31
• Status Verified: 2024-08
• Last Update Submitted: 2024-08-09
• Last Update Posted: 2024-08-12
• Primary Completion: 2024-12-31
• Study Completion: 2024-12-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 80

Inclusion Criteria

All participants

• Aged 18-35
• Able to provide written, informed consent
• NIH Toolbox age-adjusted Cognitive Function Composite standard score ≥ 85
• Native English speaker
• Right-handed
• Not pregnant
• Able to attend all study sessions
• Pass safety screening for MRI and neuromodulation (e.g. no metal in body, implanted devices, history of seizure, claustrophobia)

Additional INCLUSION criteria for adults with autism Either

• Prior research-reliable diagnosis of autism spectrum disorder (ASD) Or
• Meet DSM-5 criteria for ASD confirmed with ADOS-2 via research-reliable clinical assessment

Exclusion Criteria

Neurotypical adults

• Age <18 or >35
• NIH Toolbox age-adjusted Cognitive Function Composite standard score < 85
• Contraindications for MRI or neuromodulation with tDCS (e.g. metal in body, pacemaker or other implanted device, history of seizure, claustrophobia)
• Current or prior history of neurological or neurodevelopmental condition or brain injury
• Psychotropic medication
• Pregnancy

Adults with autism

• Age <18 or >35
• Participants with a legal authorized representative
• NIH Toolbox age-adjusted Cognitive Function Composite standard score < 85
• Contraindications for MRI or neuromodulation with tDCS (e.g. metal in body, pacemaker or other implanted device, history of seizure, claustrophobia)
• Pregnancy

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Right cerebellum	Transcranial direct current stimulation	Participants (neurotypical, autistic) in this arm will receive tDCS targeting the right posterolateral cerebellum (lobule VII). All participants will receive anodal, cathodal and sham tDCS.
Posterior vermis	Transcranial direct current stimulation	Participants (neurotypical, autistic) in this arm will receive tDCS targeting the posterior cerebellar vermis. All participants will receive anodal, cathodal and sham tDCS.

Primary Outcome Measures

Name	Time	Method
Cyberball social ball-playing task	Within 30min post-tDCS
Functional MRI data	Within 45min post-tDCS	Functional MRI task data and resting state functional connectivity data
Reading the Mind in the Eyes Test Adult Version	Within 30min post-tDCS
Flexible Item Selection Test	Within 30min post-tDCS

Trial Locations

Locations (1)

American University; 🇺🇸 Washington, District of Columbia, United States