Clinical Research Directory

Inclusion Criteria: * For participants with dementia: 1. Clinical diagnosis of probable Alzheimer's disease (AD) or mild cognitive impairment (MCI) due to AD, based on established diagnostic criteria. 2. Presence of at least one prominent behavioral or psychological symptom of dementia (BPSD), including depression, agitation, apathy, or nighttime sleep disturbance. 3. Prominent is defined as: NPI single-item score ≥ 4 (severity × frequency), or NPI-Q severity score ≥ 2, or PSQI total score ≥ 5 (if sleep disturbance is the main symptom). 4. Stable living arrangement or care environment for at least two weeks before enrollment. 5. If receiving any pharmacological or non-pharmacological treatments for BPSD, the dosage and frequency must have remained stable for at least two weeks prior to study participation. 6. Able and willing to provide informed consent; for those lacking decision-making capacity, consent must be obtained from a legally authorized representative. * For primary caregivers: 1. Adult primary caregiver of the enrolled participant. 2. If receiving treatment for caregiver stress, the dosage and frequency must have been stable for at least two weeks before enrollment. 3. Willing and able to provide informed consent. Exclusion Criteria: * Any medical condition that may increase risk during participation, including: 1. Retinal disease, active use of photosensitizing medications, recent ocular surgery (within 4 weeks), or photosensitivity disorders (e.g., epilepsy). 2. Unstable physical or mental condition deemed unsuitable by investigators, such as acute delirium or active respiratory infection (including COVID-19)