Inclusion Criteria:

1. Aged 18 years and above, regardless of gender;
2. Meet the DSM-5 diagnostic criteria for mental disorders (any type);
3. Insomnia Severity Index (ISI) score ≥11;
4. Have at least 7 hours of sleep time available;
5. Able to complete the 2-month scale assessment and follow-up plan;
6. Voluntarily sign the informed consent form;
7. Intend to receive lemborexant treatment as judged by the clinicians

Exclusion Criteria:

1. Mental disorder is in the acute phase as judged by clinical assessment, or the dose of other psychotropic drugs cannot be stabilized during the study;
2. Concurrent use of ≥2 types of benzodiazepine receptor agonists (BZRAs) as insomnia treatment drugs;
3. Previous continuous use of dual orexin receptor antagonist (DORA)-type drugs for >1 week;
4. Clear suicide attempt/plan or high suicide risk as judged by the researcher;
5. Pregnant or lactating women;
6. Patients with narcolepsy;
7. Patients with severe hepatic insufficiency;
8. Currently accompanied by severe or unstable diseases of cardiovascular, respiratory, digestive and other systems;
9. Other conditions deemed unsuitable for participation by the researcher