Transcranial Alternating Current Stimulation (tACS) to Improve Motor Skill Acquisition in Stroke Patients

Not Applicable

Completed

• Conditions: Stroke
• Interventions: Device: Sham-tACS; Device: TGP-tACS

• Registration Number: NCT05576129
• Lead Sponsor: Universitätsklinikum Hamburg-Eppendorf

Brief Summary

Hand motor function is often severely affected in stroke patients and its recovery is one primary goal in stroke rehabilitative treatment programs. Recently, theta-gamma transcranial alternating current stimulation (tACS) has been shown to enhance motor skill acquisition in healthy individuals. The aim of the present study is to examine the effect of theta-gamma tACS on motor skill acquisition in chronic stroke patients.

Detailed Description

Hand motor function is often severely affected in stroke patients and recovery of function is a primary goal in stroke rehabilitative treatment programs. Recently, theta-gamma tACS has been shown to enhance motor skill acquisition in healthy individuals \[Akkad et al.2021\]. The aim of the present study is to examine the effect of theta-gamma tACS on motor skill acquisition in chronic stroke patients.

In a randomized, controlled, triple-blind trial, chronic stroke patients with an initially impaired hand motor function will receive either (i) theta-gamma peak stimulation (TGP) or (ii) sham stimulation. TGP stimulation significantly improved motor learning in the study by Akkad et al (2021) compared to sham stimulation. tACS will be delivered through a five-electrode montage centered over the sensorimotor cortex on the lesioned side of the brain for approximately 38 min. During stimulation patients will perform a motor skill acquisition task performed with the affected hand. The task consists of short repetitive trials in which participants alternately press two buttons with their thumb. It is designed in a way that participants can improve their performance, more precisely the speed of button presses, and are encouraged to do so. To reduce skin sensations beneath the stimulation electrodes and thereby improve blinding compared to sham stimulation, a local anesthetic consisting of lidocaine and prilocaine will be administered underneath the stimulation electrodes.

Based on the results of the study by Akkad et al. (2021) and on the assumption that theta-gamma phase amplitude coupling is a key mechanism for motor skill acquisition, the investigators hypothesize that motor skill acquisition will differ significantly between the TGP and sham group.

Study Timeline

• Study First Submitted: 2022-10-07
• Study First Submitted QC: 2022-10-07
• Study First Posted: 2022-10-12
• Study Start: 2022-11-14
• Primary Completion: 2023-08-25
• Study Completion: 2023-08-25
• Status Verified: 2024-12
• Last Update Submitted: 2024-12-16
• Last Update Posted: 2024-12-20

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

• German-speaking
• ability to perform a thumb movement task with the affected hand
• first-ever clinical ischemic stroke in the chronic phase
• persistent mild motor deficit of the upper extremity or motor deficit of the upper extremity in the acute phase over >24h

Exclusion Criteria

• pronounced cognitive deficits
• history of major neurological or psychiatric illness other than stroke
• epilepsy or epileptic seizure in the history
• any devices or implants in the head region (e.g. cochlear implant, aneurysm clips),
• implanted pacemaker or medical pumps
• intake of psychotropic medication
• allergy to any ingredient of the local anesthetic cream
• pregnancy

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Sham-tACS	Sham-tACS	Patients perform a motor skill acquisition task with the affected hand during sham-stimulation over the sensorimotor cortex on the lesioned side.
TGP-tACS	TGP-tACS	Patients perform a motor skill acquisition task with the affected hand during TGP-stimulation over the sensorimotor cortex on the lesioned side.

Primary Outcome Measures

Name	Time	Method
Motor Skill Acquisition	Over the course of the motor task with a duration of 38 minutes and 20 seconds.	Quotient of mean "Duration of Button Presses" of the best block and the baseline block. Best block is defined as the block with the lowest mean "Duration of Button Presses". "Duration of Button Press" is the Duration between the first and fourth button press of a valid trial.

Secondary Outcome Measures

Name	Time	Method
Duration of Button Presses	Baseline (consisting of 20 trials) and each of 6 blocks (consisting of 40 trials each)	Time span from first to last button press of a trial. Averaged for all trials of one block

Trial Locations

Locations (1)

Department of Neurology, University Medical Center Hamburg-Eppendorf; 🇩🇪 Hamburg, Germany