Study on the Optimal Waveform Patterns of Electroacupuncture Targeted Intervention for Bell's Palsy Based on Surface Electromyography Characteristics

The goal of this clinical study is to find out whether different electronic acupuncture wave forms can effectively treat recovery-stage Bell's palsy in adults and evaluate their safety. The main questions it aims to answer are: * Can targeted electronic acupuncture wave forms improve facial nerve function in patients with Bell's palsy? * What is the optimal electronic acupuncture waveform for different degrees of facial nerve injury? * What adverse events may occur during electronic acupuncture treatment? Researchers will compare low-frequency continuous wave electronic acupuncture and intermittent wave electronic acupuncture to determine which waveform works better for recovery-stage Bell's palsy. Participants will: * Receive either low-frequency continuous wave electronic acupuncture or intermittent wave electronic acupuncture every other day for 4 weeks * Undergo surface sEMG and ENoG examinations at baseline, Week 2, and Week 4 * Complete facial function assessments and safety evaluations at each clinic visit

Inclusion Criteria for Bell's Palsy Subjects： * Meet the above Bell's palsy diagnostic criteria; * Age 18-65 years, either gender; * Disease course in recovery phase (21 days ≤ course ≤ 6 months) and not recovered (FNGS 2.0 score \>4); * Voluntarily participate in this study and sign informed consent. Inclusion Criteria for Healthy Subjects： * Do not meet the above Bell's palsy diagnostic criteria; * Age 18-65 years, either gender, matched to Bell's palsy subjects within 5 years for age and gender; * Normal facial nerve function, FNGS 2.0 score = 4; * Voluntarily participate in this study and sign informed consent. Exclusion Criteria for Bell's Palsy Subjects： * Facial trauma, skin lesions, or other diseases that may cause facial paralysis symptoms; * Diagnosed with Ramsay Hunt syndrome (herpes zoster oticus); * Bilateral facial paralysis; * Previous history of facial paralysis; * Facial synkinesis, contracture, or spasm already present; * History of facial surgery; * Uncontrolled diabetes, hypertension, severe cardiac, hepatic, or renal disease, cognitive impairment, aphasia, or mental disorders; * Pacemaker use; * Pregnant or lactating patients. Exclusion Criteria for Healthy Subjects： * Facial trauma, skin lesions, or other diseases that may affect facial muscle activity; * Previous history of facial paralysis; * History of facial surgery; * Uncontrolled diabetes, hypertension, severe cardiac, hepatic, or renal disease, cognitive impairment, aphasia, or mental disorders; * Pacemaker use; * Pregnant or lactating patients.