How Does Cerebellar tDCS Alter Intracortical Inhibition Over Time?

NCT06384495 | Terminated

• 1 other identifier: STUDY00021475
• Study Type: interventional
• Target: 3
• Locations: 1 country
• Sites: 1

Brief Summary

Combining cortical tDCS with behavioral interventions has been shown to have beneficial outcomes in individuals post-stroke. However, cerebellar tDCS is a fairly new approach for individuals with unilateral cortical stroke and there has not been reports of duration of effect of tDCS applied to the cerebellum in this population. Information gained from this study will serve to fill knowledge gaps on the duration of effect of cerebellar tDCS and the effects of polarity. The purpose of this study is to determine the duration of effect of ventro-lateral cerebellar transcranial direct current stimulation (tDCS) in healthy adults through cortical excitability (CE), cognitive, language and motor assessment measures. Primary aim: Compare baseline CE from left motor cortex of first dorsal interosseous (FDI) and orbicularis oris (OO) areas to CE post cerebellar tDCS at 15 minutes, 45 minutes and 75 minutes. Single-pulse and paired-pulse transcranial magnetic stimulation (TMS) will be used to measure and compare stimulus response curve (S/R curve), cortical silent period (CSP) and short-interval intracortical inhibition (SICI) in the hand area and facial area of the left primary motor cortex at each time point. Secondary aim: Compare baseline performance on cognition, motor learning and language tasks to performance at 15, 45 and 75 minutes after receiving tDCS. Digit Symbol Substitution Test (DSST), Serial Reaction Time Test (SRTT) and Lexical Decision tasks will be presented via a computer interface.

Conditions

Stroke

Outcome Measures

Primary Outcomes (3)

• stimulus/response curve (S/R Curve)

  change of motor evoked potential (MEP) as reflected in EMG from 1) hand (FDI muscle) and 2) mouth (orbicularis oris muscle).following single pulse transcranial magnetic stimulation (TMS) to the primary motor cortex of varying intensities.

  baseline, 15,45 and 75 minutes post-tDCS

• Cortical Silent Period (CSP)

  Change in silent period of a contracted muscle shown through EMG from 1) hand (FDI muscle) and 2) mouth (orbicularis oris muscle). following a single supra-threshold stimulus pulse to the primary motor cortex using TMS.

  baseline, 15,45 and 75 minutes post-tDCS

• Short-interval Intracortical Inhibition (SICI).

  Change in MEP as reflected in EMG from 1) hand (FDI muscle) and 2) mouth (orbicularis oris muscle). following a subthreshold conditioning pulse followed by a suprathreshold test pulse

  baseline, 15,45 and 75 minutes post-tDCS

Secondary Outcomes (3)

• Digit Symbol Substitution Test (DSST)

  baseline, 15, 45 and 75 minutes post stimulation

• Serial Reaction Time Test (SRTT)

  baseline, 15, 45 and 75 minutes post stimulation

• Lexical Decision Task

  baseline, 15, 45 and 75 minutes post stimulation

Study Arms (3)

Real anodal tDCS group (REAL-A)

EXPERIMENTAL

Participants randomized to REAL-A

Procedure: REAL-A

Real cathodal tDCS group (REAL-C)

EXPERIMENTAL

Participants randomized to REAL-C

Procedure: REAL-C

Sham group (SHAM)

SHAM COMPARATOR

Participants randomized to SHAM group

Procedure: SHAM

Interventions

REAL-A PROCEDURE

one session of 2mA for 20 minutes to the right ventro-lateral cerebellum

Real anodal tDCS group (REAL-A)

REAL-C PROCEDURE

one session of 2mA for 20 minutes to the right ventro-lateral cerebellum

Real cathodal tDCS group (REAL-C)

SHAM PROCEDURE

one session of sham tDCS for 20 minutes to the right ventro-lateral cerebellum.

Sham group (SHAM)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Eligible participants must be over the age of 18 years of age
• must be fluent in English
• have adequate vision to see a computer screen from 12-18 inches, fine motor skills to press a key on a computer keyboard and hearing to hear directions and questions provided by the researcher
• Individuals must also be able to read words and phrases

You may not qualify if:

• Pregnancy
• history of seizures
• neurologic injury including concussion/head injury or stroke or other neurologic conditions
• History of documented learning disabilities and/or ADHD
• Metal implants in the body (excluding dental fillings), psoriasis or eczema affecting the scalp.

Sponsors & Collaborators

• University of Minnesota: lead

Study Sites (1)

University of Minnesota

Minneapolis, Minnesota, 55414, United States

Location

MeSH Terms

Conditions

Stroke

Interventions

salicylhydroxamic acid

Condition Hierarchy (Ancestors)

Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases

Study Officials

• Sharyl Samargia-Grivette

  University of Minnesota

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 22, 2024
• First Posted: April 25, 2024
• Study Start: July 15, 2024
• Primary Completion: August 10, 2025
• Study Completion: August 10, 2025
• Last Updated: August 24, 2025

Record last verified: 2025-08

Locations

US (1)