Overview
This randomized, double-blind, placebo-controlled trial will investigate whether repetitive transcranial magnetic stimulation (rTMS) applied to the dorsolateral prefrontal cortex (DLPFC) can enhance the effects of dual-task gait training in people with chronic stroke. Participants will be randomly allocated to receive either active rTMS or sham rTMS immediately before the same standardized dual-task gait training program.
The intervention includes 12 sessions over 3 weeks. Outcomes will be assessed at baseline, immediately after training, and at 4-week follow-up. Co-primary outcomes are dual-task mobility and cognitive performance during walking, quantified using dual-task cost (DTC) for gait speed and cognitive-task performance during dual-task walking (e.g., Serial 7s; Shopping List Recall). Secondary outcomes include balance/mobility, community participation, mood/sleep measures, and fall incidence.
To explore mechanisms, prefrontal cortex activity during single- and dual-task walking will be recorded using functional near-infrared spectroscopy (fNIRS), and mediation analyses will examine whether changes in PFC activity explain intervention effects.
Description
Cognitive-motor interference after stroke can reduce walking safety and functional independence, especially during everyday dual-task situations. Dual-task gait training can improve performance, but response varies, potentially due to limitations in executive control and prefrontal network engagement. The DLPFC is central to attention and executive function; therefore, rTMS targeting the DLPFC may prime relevant neural circuits and improve responsiveness to subsequent dual-task training.
This study is a parallel-group, randomized, double-blind, placebo-controlled trial. Community dwelling adults with chronic unilateral stroke will be recruited and randomized 1:1. Participants and outcome assessors will be blinded.
Both groups will complete 12 supervised sessions over 3 weeks. In each session, participants will first receive either: Active rTMS to the DLPFC of the affected hemisphere (5 Hz; 90% resting motor threshold; total 1,200 pulses), or Sham rTMS using the placebo side of the coil with similar auditory sensations.
Dual-task gait training will begin shortly after stimulation. Training will combine functional walking/balance tasks with progressively challenging cognitive tasks (e.g., mental arithmetic, verbal fluency, working memory tasks, and a shopping-list recall task), with difficulty adjusted to participant ability.
Assessments will be conducted at baseline, post-intervention, and 4-week follow-up. Co-primary outcomes are DTC of gait speed and cognitive performance during dual-task walking.
Eligibility
Inclusion Criteria:
- Unilateral ischemic or hemorrhagic hemispheric stroke
- Age ≥ 50 years
-≥ 6 months post-stroke
- Medically stable
- Able to walk independently ≥ 1 minute (assistive device allowed)
- Able to follow commands
- mRS 1-3
- MoCA ≥ 22
Exclusion Criteria:
- Other neurological disorders
- Cerebellar/brainstem injury
- TMS contraindications (e.g., pacemaker, intracranial metal, seizure history, pregnancy)
- Contraindications to exercise (e.g., unstable angina)
- Severe aphasia (NIHSS item 9 ≥ 2)
- Pain/illness limiting performance
- Concurrent formal rehabilitation elsewhere
- RMT cannot be determined
- Fails TMS safety screening