Repetitive Transcranial Magnetic Stimulation Primed Self-controlled Practice on Motor Learning

Summary

This study aims to investigate the additive effects of combining self-controlled practice with repetitive transcranial magnetic stimulation (rTMS) pretreatment on motivation enhancement and motor learning performance in healthy young adults. According to the "Optimizing Performance Through Intrinsic Motivation and Attention for Learning" (OPTIMAL) theory, numerous studies have demonstrated that providing learners with autonomy during practice can facilitate intrinsic motivation and motor learning. However, self-controlled practice alone may have limited effects, and further interventions may be required to amplify learning outcomes.

In recent years, non-invasive brain stimulation techniques-particularly high-frequency (facilitatory) rTMS applied to the dorsolateral prefrontal cortex (DLPFC)-have been shown to enhance motivational drive and explicit learning performance by strengthening the connectivity of the DLPFC-midbrain dopamine pathway. For example, 10 Hz high-frequency stimulation can significantly improve learners' accuracy and motivation. Interestingly, several sequence learning studies have found that low-frequency (inhibitory) rTMS, when used as a priming intervention, can instead enhance implicit procedural learning. This effect may occur because inhibiting the lateral prefrontal cortex reduces its top-down suppression of implicit learning systems, thereby releasing procedural learning potential.

Based on the theory of metaplasticity, applying facilitatory or inhibitory stimulation beforehand can alter the threshold of synaptic plasticity, thus influencing subsequent learning outcomes. Therefore, this study designed two DLPFC pretreatments-facilitatory and inhibitory-and combined them with self-controlled practice to systematically examine the interaction between different stimulation protocols on motivation and motor learning.

This cross-sectional experiment plans to recruit 72 healthy participants aged 20 or older, randomly assigned to one of six groups: (1) facilitatory rTMS + self-controlled practice, (2) facilitatory rTMS + yoked control, (3) inhibitory rTMS + self-controlled practice, (4) inhibitory rTMS + yoked control, (5) sham rTMS + self-controlled practice, and (6) sham rTMS + yoked control.

The experiment will last for seven days. On Day 1, participants will complete baseline testing, followed by facilitatory rTMS, inhibitory rTMS, or sham stimulation over the DLPFC. Immediately afterward, they will engage in a trajectory-tracking learning task (manipulating a joystick to reproduce a sine-wave pattern). After practice, participants will complete a motivation assessment. During the trajectory-tracking task, the self-controlled group can choose when to receive feedback to adjust their learning, whereas the yoked control group will receive feedback at time points matched to their paired counterpart.

On Day 2, participants will again receive the assigned rTMS (facilitatory, inhibitory, or sham), complete the trajectory-tracking task, and undergo a motivation assessment. After a five-minute rest, they will perform retention and transfer tests, followed by TMS measurement of cortical excitability. On Day 7, participants will return to the laboratory to complete another retention and transfer test, along with cortical excitability measurement via TMS.

The primary behavioral outcomes are the root mean square error (RMSE) and error estimation (EE) in the trajectory-tracking task. Motivation will be assessed using the Intrinsic Motivation Inventory (IMI). As there have been no prior studies combining DLPFC rTMS pretreatment with practice autonomy, the results of this experimental design are expected to provide new insights and references for enhancing motor learning ability in healthy adults.

Conditions

• rTMS Stimulation
• Autonomy
• Healthy Young Adults

Interventions

DEVICE

rTMS - cTBS (Continuous Theta-Burst Stimulation)

Continuous theta-burst stimulation (cTBS) is a patterned form of rTMS consisting of bursts of three pulses at 50Hz, repeated every 200ms (5Hz), administered continuously without breaks. In this study, cTBS is delivered over the target cortical area according to established safety guidelines (e.g., a continuous 40s train for a total of 600 pulses) at an intensity set as a percentage of the resting motor threshold. The procedure is used to induce a transient reduction in cortical excitability as a priming intervention prior to motor practice.

BEHAVIORAL

Self-controlled (autonomy)

Self-controlled practice is a motor learning intervention in which participants are granted autonomy to make choices about key aspects of their practice sessions (e.g., when to receive feedback, the sequence/timing of trials, or selection of specific practice parameters). This design allows participants to actively control elements of the training experience according to their preference, thereby fostering intrinsic motivation and engagement. The intervention is grounded in the OPTIMAL theory of motor learning, which highlights the role of autonomy support in enhancing learning outcomes and motivation. In this study, participants in the self-controlled practice group make their own decisions regarding practice conditions, in contrast to yoked controls who follow externally assigned parameters.

DEVICE

Sham

Sham TBS involves the application of a sham theta-burst stimulation protocol designed to mimic the sensory experience of active TBS without delivering effective magnetic pulses to the brain. This is typically achieved by angling the coil to prevent cortical stimulation. The procedure controls for placebo effects and participant expectations while ensuring blinding. The sham stimulation session matches the timing and setup of active TBS interventions but does not induce cortical excitability changes.

BEHAVIORAL

Yoked Practice

Yoked practice refers to a motor learning protocol in which participants perform tasks under externally controlled practice conditions, matched to the parameters (e.g., feedback) of a paired participant from a self-controlled practice group. This design removes participant autonomy over practice choices, allowing comparison between self-controlled and externally controlled practice to evaluate the effects of autonomy on motor learning and motivation.

DEVICE

rTMS- iTBS (Intermittent Theta-Burst Stimulation)

Intermittent theta-burst stimulation (iTBS) is a patterned form of repetitive transcranial magnetic stimulation (rTMS) consisting of bursts of three pulses at 50Hz, repeated every 200ms (5Hz). In this study, iTBS is delivered over the target cortical area using standard protocols (e.g., 2s trains of TBS repeated every 10s for a total of 600 pulses) at an intensity set as a percentage of the resting motor threshold. The procedure aims to facilitate cortical excitability as a priming intervention prior to motor practice.

Sponsors & Collaborators

• National Science and Technology Council, R.O.C.

  collaborator UNKNOWN

• National Taiwan University Hospital

  lead OTHER

Study Design

Allocation

NON_RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

35 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-09-01

Primary Completion

2028-12-31

Completion

2028-12-31

Countries

• Taiwan

Study Locations