High-definition Transcranial Electrical Stimulation for Upper Extremity Rehabilitation

Inclusion Criteria:

• Sub-Project 1 (Healthy)

1. Adults aged 18 and above.

2. Confirmed right-handedness using the Edinburgh Handedness Inventory.

Sub-Project 1 (Post-stroke patients)

1. Aged 18 and above.

2. Diagnosed with stroke.

3. Post-stroke for more than 6 months.

4. Unilateral hemiparesis.

Sub-Project 2 (Subacute-stroke patients)

1. Aged 18 and above.

2. Diagnosed with stroke.

3. Stroke occurred between 7 days to 6 months ago.

4. Unilateral hemiparesis.

5. Degree of recovery for proximal and distal movements of the affected upper limb isBrunnstrom stage III to V.

6. No severe muscle spasticity in any segments of the affected upper limb (ModifiedAshworth Scale ≤ 2).

Exclusion Criteria:

• Sub-Project 1 (Healthy)

1. History of neurological disorders (e.g., stroke, brain tumor, epilepsy), psychiatricdisorders (e.g., substance abuse, major depression, schizophrenia, bipolardisorder), or musculoskeletal disorders of the upper limb.

2. Contraindications to transcranial electrical stimulation, including history ofepilepsy, atrial fibrillation, presence of metal implants, cardiac pacemakers,convexity skull defects, or increased intracranial pressure.

3. Skin allergies, contact dermatitis, abnormal pain, hypersensitivity to pain, wounds,or ulcers on the head.

4. Participation in other invasive or non-invasive brain stimulation research studies.

5. Pregnancy or lactating women. (If female, must be postmenopausal or surgicallysterilized. Fertile women must have a negative pregnancy test result. Fertile femalepatients engaging in heterosexual intercourse, as well as fertile male patients withfertile female partners, must agree to use effective contraception during the trialperiod and for 4 months after the last dose of the investigational drug, such asoral contraceptives, dual barrier methods, intrauterine devices, or abstain fromsexual intercourse during this period; non-fertile women are those who haveundergone bilateral oophorectomy or are postmenopausal.)

6. History of alcohol or substance abuse.

7. Damaged skin at the stimulation site, electrode contact, or device wearing site.

8. Long-term use of central nervous system affecting medications (such asantidepressants, sedatives) or other medications that may affect seizure threshold.

9. Other conditions deemed unsuitable for transcranial electrical or magneticstimulation by a physician.

10. Affiliation with any research institution/execution unit (e.g., students from NTU,Taipei Medical University).

Sub-Project 1 (Post-stroke patients)

1. Contraindications to transcranial electrical stimulation include a history ofepilepsy, atrial fibrillation, presence of metal implants, cardiac pacemakers,convexity skull defects, or increased intracranial pressure.

2. Skin allergies, contact dermatitis, abnormal pain, hypersensitivity to pain, wounds,or ulcers on the head.

3. Severe neurological or psychiatric disorders other than stroke (such as majordepression, schizophrenia, substance abuse, organic brain diseases, Parkinson'sdisease, brain tumors).

4. Use of medications that may lower the seizure threshold.

5. Undergoing other invasive or non-invasive brain stimulation therapies.

6. Pregnancy or lactating women. (If female, must be postmenopausal or surgicallysterilized. Fertile women must have a negative pregnancy test result. Fertile femalepatients engaging in heterosexual intercourse, as well as fertile male patients withfertile female partners, must agree to use effective contraception during the trialperiod and for 4 months after the last dose of the investigational drug, such asoral contraceptives, dual barrier methods, intrauterine devices, or abstain fromsexual intercourse during this period; non-fertile women are those who haveundergone bilateral oophorectomy or are postmenopausal.)

7. History of alcohol or substance abuse.

8. Damaged skin at the stimulation site, electrode contact, or device wearing site.

9. Long-term use of central nervous system affecting medications (such asantidepressants, sedatives) or other medications that may affect seizure threshold.

10. Other conditions deemed unsuitable for transcranial electrical or magneticstimulation by a physician.

Sub-Project 2 (Subacute-stroke patients)

1. Contraindications to transcranial electrical stimulation include a history ofepilepsy, atrial fibrillation, presence of metal implants, cardiac pacemakers,convexity skull defects, or increased intracranial pressure.

2. Skin allergies, contact dermatitis, abnormal pain, hypersensitivity to pain, wounds,or ulcers on the head.

3. Severe neurological or psychiatric disorders other than stroke (such as majordepression, schizophrenia, substance abuse, organic brain diseases, Parkinson'sdisease, brain tumors).

4. Use of medications that may lower the seizure threshold.

5. Other muscle and joint problems affecting upper limb function, such as jointcontractures, rheumatoid arthritis, myositis ossificans.

6. Severe cognitive impairment or receptive or global aphasia making it difficult tounderstand instructions.

7. Hemineglect (including visual, auditory, or sensory neglect).

8. Undergoing other invasive or non-invasive brain stimulation therapies.

9. Pregnancy or lactating women. (If female, must be postmenopausal or surgicallysterilized. Fertile women must have a negative pregnancy test result. Fertile femalepatients engaging in heterosexual intercourse, as well as fertile male patients withfertile female partners, must agree to use effective contraception during the trialperiod and for 4 months after the last dose of the investigational drug, such asoral contraceptives, dual barrier methods, intrauterine devices, or abstain fromsexual intercourse during this period; non-fertile women are those who haveundergone bilateral oophorectomy or are postmenopausal.)

10. History of alcohol or substance abuse.

11. Damaged skin at the stimulation site, electrode contact, or device wearing site.

12. Long-term use of central nervous system affecting medications (such asantidepressants, sedatives) or other medications that may affect seizure threshold.

13. Other conditions deemed unsuitable for transcranial electrical or magneticstimulation by a physician.