NCT07089069

Intensity-Dependent Effects of 4-week Transcranial Direct Current Stimulation on Motor Learning in Healthy Young Adults

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 44 (estimated)
• Sponsor: Beijing Sport University · Academic / Other
• Sex: All
• Age: 18 Years – 25 Years
• Healthy volunteers: Accepted

Summary

The goal of this clinical trial is to investigate the effects of different intensities of transcranial direct current stimulationover primary motor cortex on motor learning in healthy adults. The main question it aims to answer is: Which intensity of tDCS can best improve motor learning? Researchers will compare 1 mA, 2 mA, and 3 mA tDCS to sham tDCS to see which intensity of tDCS is most effective in improving the ability of motor learning. Participants will be randomly divided into four groups and receive 4 different intensities of tDCS(1 mA, 2 mA, 3 mA and sham tDCS),and will be blinded to the type of tDCS they received. We hypothesized that anodal tDCS at 2 mA would produce the most substantial improvement in motor learning.

Detailed description

The present study aimed to investigate the effects of different intensities of tDCS-specifically 1 mA, 2 mA, and 3 mA-on motor learning in healthy adults. Both the acute effects following a single tDCS session and the cumulative effects after a 4-week intervention (10 sessions) were evaluated. Additionally, the study aimed to determine whether improvements in motor learning induced by 4 weeks of repeated tDCS would be sustained one week after completion of the intervention. We hypothesized that anodal tDCS at 2 mA would produce the most substantial improvement in motor sequence learning, both following a single session and after a 4-week intervention, compared to 1 mA, 3 mA, and sham stimulation. Furthermore, we expected that the motor learning gains observed in the 2 mA group would be sustained one week post-intervention, indicating the persistence of tDCS-induced effects. In contrast, we anticipated minimal improvement in the 1 mA group due to insufficient stimulation intensity, and no additional or even reduced benefits in the 3 mA group compared to the 2 mA group.

Conditions

• Transcranial Direct Current Stimulation (tDCS)

Interventions

Type	Name	Description
DEVICE	3 mA transcranial direct current stimulation	The intervention will be conducted using a battery-powered stimulator (TCS-E2000, Shenzhen Yingchi Technology Co., Ltd) through a pair of saline-soaked sponge electrodes (5 cm × 7 cm).The stimulation intensity will be set at 3 mA. The stimulation will last for 20 minutes each time, with a 10 s fade-in period at the start and a 10-s fade-out period at the end of stimulation. The participants will receive intervention lasting for four weeks(10 sessions).The anodal electrode will be placed over the primary motor cortex (M1), and the reference electrode will be positioned at the center of the forehead.
DEVICE	2 mA transcranial direct current stimulation	The intervention will be conducted using a battery-powered stimulator (TCS-E2000, Shenzhen Yingchi Technology Co., Ltd) through a pair of saline-soaked sponge electrodes (5 cm × 7 cm).The stimulation intensity will be set at 2 mA. The stimulation will last for 20 minutes each time, with a 10 s fade-in period at the start and a 10-s fade-out period at the end of stimulation. The participants will receive intervention lasting for four weeks(10 sessions).The anodal electrode will be placed over the primary motor cortex (M1), and the reference electrode will be positioned at the center of the forehead.
DEVICE	1 mA transcranial direct current stimulation	The intervention will be conducted using a battery-powered stimulator (TCS-E2000, Shenzhen Yingchi Technology Co., Ltd) through a pair of saline-soaked sponge electrodes (5 cm × 7 cm).The stimulation intensity will be set at 1 mA. The stimulation will last for 20 minutes each time, with a 10 s fade-in period at the start and a 10-s fade-out period at the end of stimulation. The participants will receive intervention lasting for four weeks(10 sessions).The anodal electrode will be placed over the primary motor cortex (M1), and the reference electrode will be positioned at the center of the forehead.
DEVICE	sham transcranial direct current stimulation	The intervention will be conducted using a battery-powered stimulator (TCS-E2000, Shenzhen Yingchi Technology Co., Ltd) through a pair of saline-soaked sponge electrodes (5 cm × 7 cm).The intervention will last for 20 minutes each time, with a 10 s fade-in period at the start and a 10-s fade-out period at the end of stimulation，but there is not current in between. The participants will receive intervention lasting for four weeks(10 sessions).The anodal electrode will be placed over the primary motor cortex (M1), and the reference electrode will be positioned at the center of the forehead.

Timeline

• Start date: 2025-07-20
• Primary completion: 2025-09-15
• Completion: 2025-10-01
• First posted: 2025-07-28
• Last updated: 2025-07-28