Cerebellum and Autism: Regional Specialization for Social and Executive Functions

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.

Study Overview

• Status: Recruiting
• Conditions: Autism Spectrum Disorder; Autism
• Intervention / Treatment: Device: Transcranial direct current stimulation

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 Type: Interventional
• Enrollment (Estimated): 80
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Catherine Stoodley, D.Phil.; Phone Number: 202-476-4799; Email: stoodley@american.edu
• Study Contact Backup: Name: Joe Dust, M.Sc.; Email: jd7958a@american.edu

Study Locations

• United States
  • District of Columbia
    • Washington D.C., District of Columbia, United States, 20016
      • Recruiting
      • American University
      • Contact: Catherine Stoodley, D.Phil.; Phone Number: 202-885-1785; Email: stoodley@american.edu
      • Principal Investigator: Catherine Stoodley

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 35 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Please note: This study takes place at American University and Georgetown University in Washington, DC. We do not have funds for travel and lodging available for this study, so participants should be local to the DC region.

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 Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Right cerebellum; 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.	Device: Transcranial direct current stimulation; TDCS involves applying small (1-2 mA) electric currents to the scalp in order to transiently modify local neuronal electrical potentials in the brain.; Other Names: tDCS
Experimental: Posterior vermis; Participants (neurotypical, autistic) in this arm will receive tDCS targeting the posterior cerebellar vermis. All participants will receive anodal, cathodal and sham tDCS.	Device: Transcranial direct current stimulation; TDCS involves applying small (1-2 mA) electric currents to the scalp in order to transiently modify local neuronal electrical potentials in the brain.; Other Names: tDCS

What is the study measuring?

Primary Outcome Measures

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

Collaborators and Investigators

• Sponsor: American University
• Collaborators: National Institute of Mental Health (NIMH); National Institutes of Health (NIH)
• Investigators: Principal Investigator: Kathleen Gunthert, Ph.D., American University

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2022
• Primary Completion (Estimated): December 31, 2025
• Study Completion (Estimated): December 31, 2025

Study Registration Dates

• First Submitted: May 25, 2022
• First Submitted That Met QC Criteria: May 25, 2022
• First Posted (Actual): May 31, 2022

Study Record Updates

• Last Update Posted (Estimated): October 2, 2025
• Last Update Submitted That Met QC Criteria: September 29, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Neurodevelopmental Disorders; Child Development Disorders, Pervasive; Autism Spectrum Disorder; Autistic Disorder; Therapeutics; Behavioral Disciplines and Activities; Electric Stimulation Therapy; Convulsive Therapy; Psychiatric Somatic Therapies; Electroshock; Psychological Techniques; Transcranial Direct Current Stimulation
• Other Study ID Numbers: R15MH126404 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified data, including scores of behavioral tests and skull-stripped brain images, may be shared upon personal request after initial manuscripts based on this work have been published. Individuals wishing to use these data must agree not to attempt to identify participants or redistribute the data, to destroy the data after analyses are completed, and to acknowledge the data resource in any presentations or publications. For participants that consent to having their de-identified data shared with the National Database for Autism Research (NDAR), we will submit data to NDAR in accordance with the NIH guidelines (http://ndar.nih.gov/contribute.html).
• IPD Sharing Time Frame: Data uploaded to NDAR will be released following study completion
• IPD Sharing Access Criteria: Access to NDAR; Individuals wishing to use these data must agree not to attempt to identify participants or redistribute the data, to destroy the data after analyses are completed, and to acknowledge the data resource in any presentations or publications.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No