Adaptation, Ankle, Brain Connectivity, Brain Structure, Motor Learning, Stroke, Transcranial Direct Current Stimulation
Conditions
Brief summary
Ankle control is essential to safe over-ground navigation for humans. Middle- aged and older adults and patients with stroke whose ankle control is poor often lose their balance or fall. Transcranial direct current stimulation (tDCS) is an emerging non-invasive brain stimulation technology that has great potential to be applied to neurorehabilitation; however, the optimization of its applications still needs further studies. The aims of this project are to compare the effects of anodal tDCS (AtDCS) applied to the primary motor cortex (M1) contralateral to the moving leg (cM1), posterior parietal cortex (PPC) contralateral to the moving leg (cPPC), and cerebellar cortex (CBM) ipsilateral to the moving leg (iCBM) on motor learning, motor adaptation, and brain connectivity in healthy middle-aged and older adults and hemiparetic patients with chronic subcortical stroke.
Interventions
OTHERcM1 transcranial direct current stimulation
During the 5-day skill acquisition phase, all participants will undertake a 20-minute session of learning a sequential ankle tracking task with their non-dominant (for healthy adults) or affected (for patients with stroke) foot each day, using a custom-built ankle tracking system. The cM1 group will receive AtDCS stimulation at 2 mA during acquisition phase.
OTHERcPPC transcranial direct current stimulation
During the 5-day skill acquisition phase, all participants will undertake a 20-minute session of learning a sequential ankle tracking task with their non-dominant (for healthy adults) or affected (for patients with stroke) foot each day, using a custom-built ankle tracking system. The cPPC group will receive AtDCS stimulation at 2 mA during acquisition phase.
OTHERiCBM transcranial direct current stimulation
During the 5-day skill acquisition phase, all participants will undertake a 20-minute session of learning a sequential ankle tracking task with their non-dominant (for healthy adults) or affected (for patients with stroke) foot each day, using a custom-built ankle tracking system. The iCBM group will receive AtDCS stimulation at 2 mA during acquisition phase.
OTHERsham transcranial direct current stimulation
For the Sham group, the montages of the paired electrode placements will be randomly selected from the other three pairs using blocks of size 3, so that the three types of montages will have equal opportunities to be used in the Sham group. The intensity will be set at 0 mA for the Sham group. There will be a 30-second ramp-up for the Sham group. Once the current reaches 2 mA in the ramp-up period, it will drop to 0 mA for the entire 20 minutes during learning for the Sham group.
Sponsors
National Taiwan University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
40 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
Part 1: healthy middle-aged and older adults 1. age between 40 and 80 years old 2. intact cognitive function (MMSE ≧ 27) 3. normal ankle dorsiflexor and plantarflexor strength (manual muscle strength testing= 5) and passive range of motion (ankle dorsiflexion ≧10 degrees; ankle plantarflexion ≧ 45 degrees) 4. corrected far vision ≥ 0.8 (Landolt C test) and uncorrected near vision ≥ 0.04 (Comprehensive Color Blindness Checklist)
Exclusion criteria
Part 1: healthy middle-aged and older adults 1. having any contraindications for MRI or tDCS; 2. serious or uncontrolled systematic diseases; 3. symptoms or history of neurological diseases, including transient ischemic attack, stroke, epilepsy, history of abnormal electroencephalogram (EEG), meningitis, encephalitis, brain tumors, brain surgery, and sensory disorders, etc.; 4. severe musculoskeletal problems that would affect lower limb functions; 5. visual spatial perception disorders and hearing loss; 6. color blindness; 7. depression and psychiatric disorders; 8. use of any medication that could affect the central nervous system function; 9. drug, substance, or alcohol addiction; 10. those participating in research involving invasive or non-invasive brain stimulation; 11. those deemed unsuitable for MRI or tDCS after evaluation by the attending physician; 12. those affiliated with any research-conducting institution. Inclusion Criteria: Part 2: patients with chronic subcortical stroke 1. aged between 40 and 80 years old; 2. intact cognitive function (MMSE ≥ 27); 3. first-ever onset of subcortical stroke occurring at least 3 months prior to enrollment, with brain lesions involving unilateral subcortical regions only; 4. hemiplegic or hemiparetic; 5. no spatial neglect; 6. able to actively perform at least 5 degrees of ankle dorsiflexion and 10 degrees of ankle plantarflexion with the affected ankle; 7. no excessive spasticity; 8. no severe contracture (passive range of motion ≥ 10 degrees for ankle dorsiflexion and ≥ 20 degrees for ankle plantarflexion) in the affected leg; 9. mild-to moderate disability; 10. can walk independently or under supervision without assistance; 11. corrected far vision ≥ 0.8 (Landolt C test) and uncorrected near vision ≥ 0.04 (Comprehensive Color Blindness Checklist.)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change of mean RMSE value of ankle tracking performances | 1 week | Using a custom-built ankle tracking system |
| Change of Brain MRI data acquisition | 1 week | Structural images: T1- and T2 weighted imaging, fluid attenuation inversion recovery (FLAIR) images, and diffusion spectrum image (DSI) Functional image: Resting-state functional MRI (rs-fMRI) images using a T2\* gradient echo, echo-planar sequence. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Muscle strength of bilateral ankle dorsiflexors and plantarflexors | 1 week | Measured with a hand-held dynamometer |
| Mobility | 1 week | Timed Up and Go test, four square step test |
| Fall histories | 1 week | Fall Efficacy Scale (16\ 64 points, the higher score, the worsen outcome) |
| Sensory and motor functions of patients with stroke | 1 week | Fugl-Meyer Assessment |
| Balance | 1 week | One-leg stance |
| Single-task gait | 1 week | Measured with the GAITRite |
| Attention | 1 week | language-free Color Trail Test- Part 1 |
Countries
Taiwan
Contacts
Primary ContactPei-Fang Tang, PhD
Outcome results
None listed