The purpose of this study is to evaluate and compare sensory discrimination ability for electrotactile stimulation among young adults, older adults, and patients with stroke. Participants will receive non-invasive electrotactile stimulation through electrodes attached to the skin of the upper limb, such as the fingertip, palm, elbow, or shoulder, depending on the stimulation condition. The study will assess discrimination thresholds for changes in stimulation frequency, stimulation amplitude, and temporal gaps in stimulation, together with task accuracy and reaction time. The results are expected to provide foundational data for sensory assessment, electrotactile feedback design, and sensory-based rehabilitation technologies for older adults and stroke patients.
Age 19 to 54 years.
Has tactile sensation in the hands and fingers.
Provides voluntary written informed consent personally or through a legally authorized representative, if applicable.
Age 55 to 70 years.
Absence of tactile sensation in the hands or fingers.
Congenital deformity of the hands or fingers.
Presence of a major pre-existing neurogenic disease.
Presence of a major psychiatric disorder, such as major depressive disorder, schizophrenia, bipolar disorder, or dementia.