Study on the Clinical Efficacy of Transcranial Strong Alternating Current (Hi-tACS) in Patients With Neuroimmune Diseases With Insomnia

Inclusion Criteria: 1. Patients with idiopathic inflammatory demyelinating disorders (IIDDs) meeting the diagnostic criteria, including neuromyelitis optica spectrum disorders (NMOSD) \[based on the Chinese Guidelines for Diagnosis and Treatment of Neuromyelitis Optica Spectrum Disorders (2016 Edition)\] and multiple sclerosis (MS) \[based on the Chinese Guidelines for Diagnosis and Treatment of Multiple Sclerosis (2023 Edition)\], and accompanied by insomnia. * Aged between 18 and 65 years, regardless of gender. * Experiencing difficulty falling asleep, difficulty maintaining sleep, or early morning awakening on at least 3 nights per week for more than 3 months. * Severe daytime functional impairment (Chinese version of the Pittsburgh Sleep Quality Index, item 7 \[daytime dysfunction\] ≥2). * Having not taken hypnotics or insomnia treatment medication for at least 4 months. * Female participants aged 18-50 years who agree to use effective contraception throughout the study period. * Agreeing to refrain from receiving medication or other non-pharmacological treatments during the study period. * Agree to participate and sign the informed consent. 2. Patients diagnosed with chronic primary insomnia according to 《The Diagnostic and Statistical Manual of Mental Disorders》(Text Revision) (DSM-IV-TR) or 《International Classification of Diseases Tenth Revision》(ICD-10): * Aged between 18 and 65 years, regardless of gender. * Experiencing difficulty falling asleep, difficulty maintaining sleep, or early morning awakening on at least 3 nights per week for more than 3 months. * Severe daytime functional impairment (Chinese version of the Pittsburgh Sleep Quality Index, item 7 \[daytime dysfunction\] ≥2). * Having not taken hypnotics or insomnia treatment medication for at least 4 months. * Female aged 18\~50 years agreeing to adopt birth control measures during the study period. * Agreeing to refrain from receiving medication or other non-pharmacological treatments during the study period. * Agree to participate and sign the informed consent. Exclusion Criteria: * History of relapse within the past 1 month. * Drug adjustment within the past 1 month, or receipt of modified electroconvulsive therapy, transcranial magnetic stimulation therapy, or other neuralcontroltechnology therapy. * Participation in any other clinical studies within 1 month prior to enrollment or currently. * Presence of cochlear implant system, cardiac-pacemaker, or intracerebral implanted stimulators. * Impaired skin integrity at the electrode placement site, or allergy to electrode gel or adhesive. * History of organic brain diseases such as epilepsy, hydrocephalus, tumor of central nervous system, craniocerebral injury, or intracranial infection. * Pregnant or lactating women, or those intending pregnancy soon; * A score of ≥3 on the suicide item of the Hamilton Depression Scale, or coexisting severe mental disorders; * Presence of severe or unstable organic diseases; * Work night shifts; * Presence of other sleep disorders; * Poor patient compliance preventing cooperation with treatment, follow-up, or clinical, electroencephalographic (EEG), or imaging data collection; * Other circumstances deemed by the investigator as inappropriate for study participation.