High-definition Transcranial Electrical Stimulation for Upper Extremity Rehabilitation

Application of High-definition Transcranial Electrical Stimulation in the Upper Extremity Rehabilitation

Transcranial electrical stimulation (tCES) is a non-invasive and safe treatment, which uses a low direct current or alternating current to change the excitability of the cerebral cortex. The tCES has been applied in clinical trials related to rehabilitation research in recent years, and the safety and effectiveness have also been established. However,the existing tCES products effect on the whole brain networks and lack special waveforms. Therefore, we aim to develop a wearable tCES with high definition and special waveforms in this study. This novel stimulation system will result in more precise and focal stimulation of selected brain regions with special waveforms to display better neuromodulation performance. We expect that the novel high-definition tCES (HD-tCES) combined with the upper extremity rehabilitation can shorten the duration of rehabilitative periods, improve stroke patients' activity of daily living, reduce the care burden of patients' family, and subsequently decrease the cost of health care insurance.

Inclusion Criteria:

1. Age ≥ 20 years.
2. Unilateral cerebral stroke with hemiplegia in Brunnstrom stage III-V.
3. 6 months to 5 years after stroke.
4. Muscular inelasticity (spasticity) 1-3 on the affected upper limb, evaluated by the Modified Ashworth Scale.

Exclusion Criteria:

1. Extremely sensitive to electrical stimulation and cannot tolerate it.
2. Contracture on upper extremities, and limitation in joint range of motion.
3. The muscle tone was severe spasticity,
4. Ossification or inflammation in muscle tissue.
5. A history of cardiopulmonary disease or arrhythmia.
6. With implantable medical electronic devices, like pacemaker.
7. Pressure sores or wounds on the skin of head and upper extremities.
8. Metal implants in the head (neck).
9. Severe cognitive or psychiatric disorders, such as schizophrenia or dissociative identity disorder.
10. A history of seizure or other brain pathology.
11. Brain surgery or severe brain trauma.
12. Drug or alcohol abuse.
13. Malignant neoplasm or rheumatism disorder, like SLE, RA, or AS.