BSD-10CH TDCS for Upper Limb Function Improvement in Stroke Patients: a Randomized Clinical Trial

Inclusion Criteria: * Adults aged 19 years or older. * Diagnosed with stroke based on clinical observation and neuroimaging. * First-time stroke patients (1st stroke). * Stroke onset between 2 weeks and 12 months prior to screening. * Stroke lesion located in the cortex or subcortex. * Presence of hemiparesis in the upper limb. * Upper limb FMA score of 53 or lower. * Ability to read and understand the informed consent form, and to respond to questionnaires. * Willing to voluntarily participate in the clinical trial, and able to provide written informed consent to participate throughout the study period. Exclusion Criteria: * Recurrent stroke, traumatic brain injury, spinal cord injury, degenerative neurological diseases (such as Parkinson's disease), or other conditions affecting upper limb function. * MMSE score of 19 or lower, indicating dementia, and inability to follow study instructions. * Global aphasia or communication disorders. * Brain injury caused by trauma, ischemia, hypoxia, or similar conditions. * Uncontrolled medical or surgical conditions. * Skin inflammation or other dermatological issues that may prevent attachment of tDCS electrodes. * Medical contraindications for the use of tDCS devices (e.g., pacemaker, aneurysm clips, prosthetic heart valves, cochlear implants, or other implanted metal devices). * Previous use of similar stimulation devices or participation in related clinical trials within the last year. * History of major psychiatric disorders (e.g., major depressive disorder, schizophrenia, bipolar disorder, or dementia) within the past 5 years. * History of epilepsy (seizures) within the past 5 years. * History of substance abuse (e.g., neuroleptics, sedatives, narcotics, or illicit drugs) within the past 5 years. * Participants requiring changes in medications that could affect cognitive or motor function during the study (unless the participant has been on stable, prohibited medications for at least 3 months). * History of alcohol addiction treatment within the last 5 years. * Severe visual impairment that cannot be corrected with glasses, preventing the reading of standard print. * Hearing impairment that prevents communication, even with hearing aids. * Difficulty breathing at rest. * A history of suicide attempts within the past 6 months. * Pregnant or breastfeeding women, or men and women of reproductive age who do not agree to use appropriate contraception throughout the study. \*Acceptable methods of contraception include: * Hormonal methods (oral contraceptives, injections, patches, implants, etc.) * Surgical sterilization (vasectomy, bilateral tubal ligation) * Dual protection (male condoms, diaphragm, cervical cap) * Intrauterine devices or systems. * Pregnant or breastfeeding participants. * Any other clinical condition deemed by the investigator to make the participant unsuitable for the study.