Identifying Cerebral Hemodynamic Patterns in Mood Disorders and Mild Cognitive Impairment: A Functional Near-Infrared Spectroscopy (fNIRS) Study

Inclusion Criteria

General Inclusion Criteria (across all diagnostic groups):

• 18 years and older

• Ability to provide written informed consent

• Adequate cognitive and language abilities to understand and complete study tasks, including clinical assessments and fNIRS procedures

• Confirmed clinical diagnosis of major depressive disorder, bipolar disorder, or mild cognitive impairment (MCI)

• Stable psychiatric or cognitive condition, without acute episodes requiring immediate intervention

Specific Inclusion Criteria (for diagnostic groups):

• Healthy control

o No past or current psychiatric or cognitive disorder

• Major depressive disorder (MDD):

• Diagnosis of major depressive disorder, confirmed through clinical evaluation.

• No history of bipolar disorder or psychotic symptoms.

• Bipolar disorder:

o Diagnosis of bipolar disorder I or II, confirmed through clinical evaluation.

• Mild Cognitive Impairment (MCI):

• Pre-existing clinical diagnosis of mild cognitive impairment, supported by neuropsychological testing and/or MRI, PET scan data.

• No history of major psychiatric disorders, such as major depression, bipolar disorder or schizophrenia.

Exclusion Criteria

General Exclusion Criteria (across all diagnostic groups):

• Active primary psychotic or substance use disorders (except nicotine dependence) within the past year

• Any severe or unstable medical condition that could interfere with participation or data collection

• Any active neurological condition (including seizure disorder, traumatic brain injury, stroke) that could affect cognitive functioning or brain imaging results

• Inability to comply with study procedures, including cognitive testing, fNIRS assessment, or other assessments required by the protocol

• Pregnant women will be excluded due to potential physiological changes that could affect study outcomes

Specific Exclusion Criteria (for diagnostic groups):

• Healthy control

o Any past or current psychiatric or cognitive disorder

• Major depressive disorder (MDD):

• Diagnosis of bipolar disorder or schizophrenia.

• Brain stimulation therapy within the past 3 months.

• Bipolar disorder:

o Diagnosis of schizophrenia or schizoaffective disorder.

• Mild Cognitive Impairment (MCI):

• Diagnosis of dementia.

• Significant cognitive impairment preventing understanding or completion of study tasks.