NCT05576129

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

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

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 20 (actual)
• Sponsor: Universitätsklinikum Hamburg-Eppendorf · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

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.

Conditions

• Stroke

Interventions

Type	Name	Description
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 πcm² area.
DEVICE	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 πcm² area.

Timeline

• Start date: 2022-11-14
• Primary completion: 2023-08-25
• Completion: 2023-08-25
• First posted: 2022-10-12
• Last updated: 2024-12-20

Locations

1 site across 1 country: Germany