Inclusion Criteria:
1. Healthy Control Group:
* Adults aged 19 years or older.
* Able to be age- and sex-matched to the stroke cohort.
* No history of stroke, transient ischemic attack (TIA), or other central nervous system disorders.
* Cognitive function within the normal range for age and education level based on screening assessments (K-MMSE and K-MoCA).
* Able to understand the study procedures and provide written informed consent.
2. Stroke Patient Group:
* Adults aged 19 years or older.
* First-ever ischemic or hemorrhagic stroke confirmed by CT or MRI.
* Enrolled in one of the following strata according to time since stroke onset:
Stratum A: 7 days to 3 months after stroke onset. Stratum B: \>3 months to 12 months after stroke onset. Stratum C: \>12 months to 36 months after stroke onset.
\- Able to understand the study procedures and provide written informed consent, or consent provided by a legally authorized representative when applicable.
Exclusion Criteria:
1. Healthy Control Group:
* Current severe psychiatric disorders that may affect cognitive function (e.g., major depression, schizophrenia) or use of related medications.
* Strong family history of hereditary cerebrovascular disorders (e.g., CADASIL).
* Severe medical illness considered inappropriate for study participation.
* Any condition that, in the opinion of the investigator, would make participation unsuitable.
2. Stroke Patient Group:
* Impaired ability to provide consent (MMSE \<10) without an accompanying caregiver or legally authorized representative.
* History of dementia due to causes other than stroke (e.g., Alzheimer's disease) prior to stroke onset.
* History of major neurological disorders affecting cognition prior to stroke onset (e.g., Parkinson's disease, brain tumor, multiple sclerosis).
* Severe aphasia or impaired consciousness preventing completion of cognitive assessments.
* Current or pre-stroke severe psychiatric disorders that may affect cognitive function (e.g., major depression, schizophrenia) or use of related medications.
* Strong family history of hereditary cerebrovascular disorders (e.g., CADASIL).
* Contraindication to MRI (e.g., metallic implants) or refusal to provide blood samples for genomic analysis.
* Any condition that, in the opinion of the investigator, would make participation unsuitable.
