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

Stroke Clinical Trial

Official title:

Theta-gamma Transcranial Alternating Current Stimulation (tACS) to Modulate Activity in Sensorimotor Cortex for Improvement of Motor Skill Acquisition in Stroke Patients

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05576129
• Other study ID #: CFC_tACS_Stroke
• Status: Completed
• Phase: N/A
• Start date: November 14, 2022
• Est. completion date: August 25, 2023

Study information

• Verified date: October 2023
• Source: Universitätsklinikum Hamburg-Eppendorf
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 20
• Est. completion date: August 25, 2023
• Est. primary completion date: August 25, 2023
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

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

Related Conditions & MeSH terms

• Stroke

Intervention

Device:
• TGP-tACS
38 min and 20s of 4mA peak-to-peak theta-gamma stimulation with 75 Hz-gamma coupled to the peak of 6Hz-theta waves. 3s ramp-up at the beginning of stimulation and 3s ramp-down at the end of stimulation. Administered using a Starstim® device and 5 gel electrodes with a pcm² area.
• Sham-tACS
38 min and 20s of alternation between 10s of 4mA peak-to-peak TGP- tACS and a 6 min 30s stimulation-free interval. Each stimulation consists of 3s ramp-up, 4s TGP stimulation and 3s ramp-down. Administered using a Starstim® device and 5 gel electrodes with a pcm² area.

Locations

Country	Name	City	State
Germany	Department of Neurology, University Medical Center Hamburg-Eppendorf	Hamburg

Sponsors (3)

Lead Sponsor	Collaborator
Universitätsklinikum Hamburg-Eppendorf	Technical University of Twente, University of Oxford

Country where clinical trial is conducted

Germany, 

References & Publications (1)

Akkad H, Dupont-Hadwen J, Kane E, Evans C, Barrett L, Frese A, Tetkovic I, Bestmann S, Stagg CJ. Increasing human motor skill acquisition by driving theta-gamma coupling. Elife. 2021 Nov 23;10:e67355. doi: 10.7554/eLife.67355. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	"Thumb Speed" and "Thumb Acceleration"	An accelerometer will be fixed to the medial distal phalanx of the thumb. It measures the thumb acceleration in all three dimensions of space. We will use the accelerometer data for post-hoc explorative analysis.	Over the course of the motor task with a duration of 38 minutes and 20 seconds.
Primary	Motor Skill Acquisition	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.	Over the course of the motor task with a duration of 38 minutes and 20 seconds.
Secondary	Duration of Button Presses	Time span from first to last button press of a trial. Averaged for all trials of one block	Baseline (consisting of 20 trials) and each of 6 blocks (consisting of 40 trials each)