Transcranial Temporal Interference Stimulation (tTIS) for Chronic Insomnia

The purpose of this exploratory randomized controlled clinical trial is to evaluate the efficacy and safety of transcranial temporal interference stimulation (tTIS) in the treatment of chronic insomnia. The study aims to investigate whether non-invasive tTIS intervention can effectively modulate specific neural activities to improve sleep quality and alleviate related clinical symptoms in patients suffering from chronic insomnia. Participants enrolled in this study will be randomly assigned to receive either active tTIS treatment or sham stimulation. Researchers will collect clinical assessments and sleep monitoring data before, during, and after the intervention to compare the outcomes between the different groups and determine the therapeutic potential of tTIS for insomnia management.

Inclusion Criteria: 1. Aged 18 to 65 years old, male or female. 2. Eligibility required an ICD-11 diagnosis of chronic insomnia disorder, determined by investigator-administered clinical interviews (≥3 nights/week for ≥3 months, despite adequate opportunity/conditions for sleep, with daytime distress or functional impairment). 3. Insomnia Severity Index (ISI) total score ≥ 15 at screening or baseline assessment. 4. Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) total scores both ≤ 9 at screening assessment. 5. Has full civil capacity, is able to proficiently operate a smartphone and wearable sleep band, and can understand and cooperate with clinical scale assessments and neurophysiological examinations. 6. Voluntarily participates, can ensure on-time hospital visits for 10 transcranial temporal interference stimulation (tTIS) sessions over 2 consecutive weeks, and can cooperate with the 1-month longitudinal follow-up. 7. Fully understands the study purpose, intervention procedures, and potential risks, and voluntarily signs the written informed consent form. Exclusion Criteria: 1. Psychiatric conditions: (1) schizophrenia spectrum disorder or bipolar disorder, determined based on participant self-report of prior clinician diagnosis and treatment history and, when feasible, review of available medical records; (2) moderate-to-severe depressive or anxiety symptoms (PHQ-9 ≥ 10 or GAD-7 ≥ 10; either threshold met); (3) current suicidal ideation/behavior or elevated suicide risk as assessed by the investigator. 2. Secondary sleep disorders: Severe obstructive sleep apnea (OSA; AHI ≥ 30), restless legs syndrome (RLS), narcolepsy, or severe circadian rhythm disorders. 3. Epilepsy risk: History of seizures/convulsions or a clear family history of epilepsy. 4. Intracranial metal and implanted electronic devices: Intracranial metal implants (e.g., aneurysm clips, metal stents, repair patches; fixed dental fillings excluded) or implanted electronic devices (e.g., cardiac pacemakers, deep brain stimulators \[DBS\], vagus nerve stimulators \[VNS\]). 5. Medical history (neurologic): Recent craniotomy, severe traumatic brain injury, or organic brain lesions (e.g., brain tumors). 6. Special populations: Pregnant, lactating, or planning pregnancy during the study period. 7. Skin and physical restrictions: Skin damage, infection, or severe rash at the scalp stimulation site (especially over the left DLPFC and the return electrode site), or severe allergy to conductive gel/electrodes. 8. Somatic comorbidities/substance use: Severe cardiac, pulmonary, hepatic, or renal dysfunction, or other conditions deemed by the investigator to potentially affect participant safety or study assessments (e.g., severe alcohol or drug abuse).