Cerebrovascular Accident (CVA), Hemorrhage Stroke, Ischemia Stroke, Stroke
Conditions
Keywords
fatigue, electroencephalography, EEG, electromyography, EMG, transcranial alternating current stimulation, tACS
Brief summary
The goal of this interventional study is to understand the contribution of the central components to the manifestation of neuromuscular fatigue in stroke survivors. The study will include adults with a first-ever stroke in the subacute phase. The main question it aims to answer: • How does the brain activity contribute to the manifestation of neuromuscular fatigue in stroke survivors? Researchers will compare stroke participants receiving active vs sham tACS in a single session before the fatiguing contractions to determine whether central changes can influence fatigue onset/progression. Participants will: * Perform repeated leg muscle contractions until fatigue while seated in an experimental setup * Receive either active or sham tACS for 20 minutes before the fatiguing contractions. * Wear non-invasive sensors to record brain activity (EEG) and muscle activity (EMG) during the task * Complete the study during a single experimental session in which fatigue-related changes will be measured throughout the task
Interventions
DEVICETranscranial alternating current stimulation (tACS)
Transcranial alternating current stimulation (tACS) is a non-invasive brain stimulation technique that uses electrodes on the scalp to apply weak alternating electrical currents to the brain.
DEVICESham treatment
mimics active tACS but stops after 1 minute
Sponsors
Vrije Universiteit Brussel
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
First-ever stroke ≥18 years Subacute phase: 1 week to 6 months post-stroke Quadriceps (hemiplegic side) strength ≤3/5 (Medical Research Council (MRC)) Montreal Cognitive Assessment (MoCA) ≥21
Exclusion criteria
History of a previous stroke Severe spasticity (Modified Ashworth Scale (MAS) 3-4 in quadriceps/hamstrings) Other neurological, motor, musculoskeletal, or orthopedic conditions affecting trunk stability and lower limb mobility Non-cerebral strokes (e.g., brainstem, cerebellar), or dementia (MoCA ≤20) Current or former athletes. Athletes are defined as individuals who participated in organized competitive sports and engaged in structured training ≥3 sessions per week for ≥1 year within the 5 years preceding stroke Contraindications for tACS (e.g., presence of a deep brain stimulator, pacemaker, head wound, etc.).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Absolute and relative spectral power and ERD/ERS magnitude | Outcome measure will be recorded at baseline and throughout the fatiguing contractions in the single experimental session (up to 40 minutes) and compared over 4 fatigue phases. | Fatigue-related changes in sensorimotor cortical activity will be assessed using EEG-derived absolute and relative spectral power in the mu (8-12 Hz), beta (13-30/35 Hz), and gamma (30/35-100 Hz) frequency bands, as well as changes in event-related desynchronization/event-related synchronization (ERD/ERS) magnitude over time. Measurements will be obtained at pre-fatigue baseline and continuously during the fatiguing task, with data segmented into contraction epochs and grouped into four fatigue phases for analysis. |
| EMG median frequency | Outcome measure will be recorded throughout the fatiguing contractions in the single experimental session (up to 40 minutes) and compared over 4 fatigue phases. | Peripheral manifestations of fatigue will be assessed using shifts in EMG median frequency during repeated contractions. Data will be recorded continuously during the task and analyzed across contraction epochs grouped into four fatigue phases. |
| Time-to-task failure (TTF) | Outcome measure will be recorded throughout the fatiguing contractions until exhaustion | The duration a participant can sustain the prescribed fatiguing exercise until exhaustion |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Corticomuscular coherence | Outcome measure will be recorded throughout the fatiguing contractions in the single experimental session (up to 40 minutes) and compared over 4 fatigue phases. | The interaction between cortical and muscular activity will be assessed using CMC, which quantifies synchronization between EEG and EMG signals. Corticomuscular coherence will be assessed from simultaneous EEG and EMG recordings during repeated contractions and analyzed across contraction epochs grouped into four fatigue phases. |
Outcome results
None listed