An observational study in Major Depressive Disorder, Bipolar Disorder and Mild Cognitive Impairment, sponsored by Mayo Clinic. Recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-04-29.
Sponsored by Mayo Clinic · Observational
The purpose of this research is to measure brain activity in individuals with mood disorders and memory problems using a simple, safe, and noninvasive method called functional near-infrared spectroscopy (fNIRS). By comparing brain activity across different groups and relating it to symptom severity, this study aims to improve our understanding of how these conditions affect the brain.
This study will examine cerebral hemodynamic patterns in individuals with mood disorders (major depressive disorder and bipolar disorder) and cognitive disorders (mild cognitive impairment) using functional near-infrared spectroscopy (fNIRS). The primary goal is to compare hemodynamic patterns between these groups, while the secondary goal is to explore correlations between these patterns and symptom severity based on standardized clinical assessments. Additionally, electrophysiological data, including photoplethysmography (PPG) and electrocardiogram (ECG), will be analyzed to investigate autonomic nervous system activity and its relationship with cerebral hemodynamics.
3,041 studies on the registry are indexed under Depressive Disorder, Major; 588 are open to participants now.
This study's planned enrollment of 200 is above the median of 131 across 400 observational studies indexed under Depressive Disorder, Major.
Browse Depressive Disorder, Major studies →Mayo Clinic is the lead sponsor of 3,269 studies on the registry; 672 are open to participants now.
Of its 452 completed or terminated interventional studies of FDA-regulated products, 321 (71%) have results posted.
Counted across the registry records on this site, refreshed daily.
Potential participants will be identified from the Mayo Clinic outpatient clinics in the Departments of Psychiatry, Psychology, Neurology, and Primary Care.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
General Inclusion Criteria (across all diagnostic groups):
Specific Inclusion Criteria (for diagnostic groups):
Healthy control
o No past or current psychiatric or cognitive disorder
Major depressive disorder (MDD):
Bipolar disorder:
o Diagnosis of bipolar disorder I or II, confirmed through clinical evaluation.
Mild Cognitive Impairment (MCI):
Exclusion Criteria
General Exclusion Criteria (across all diagnostic groups):
Specific Exclusion Criteria (for diagnostic groups):
Healthy control
o Any past or current psychiatric or cognitive disorder
Major depressive disorder (MDD):
Bipolar disorder:
o Diagnosis of schizophrenia or schizoaffective disorder.
Mild Cognitive Impairment (MCI):
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
o No past or current psychiatric or cognitive disorder.
Other: Observational assessment using functional near-infrared spectroscopy (fNIRS), a noninvasive, portable brain imaging tool that measures changes in brain blood flow and oxygen levels.
* Diagnosis of major depressive disorder, confirmed through clinical evaluation. * No history of bipolar disorder or psychotic symptoms.
Other: Observational assessment using functional near-infrared spectroscopy (fNIRS), a noninvasive, portable brain imaging tool that measures changes in brain blood flow and oxygen levels.
o Diagnosis of bipolar disorder I or II, confirmed through clinical evaluation.
Other: Observational assessment using functional near-infrared spectroscopy (fNIRS), a noninvasive, portable brain imaging tool that measures changes in brain blood flow and oxygen levels.
* 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.
Other: Observational assessment using functional near-infrared spectroscopy (fNIRS), a noninvasive, portable brain imaging tool that measures changes in brain blood flow and oxygen levels.
Functional near-infrared spectroscopy (fNIRS) transcutaneously measures changes in oxyhemoglobin in the prefrontal cortex using light detection. It is designed to measure variations in cerebral hemodynamics on a real-time basis by radiating a near light beam, at two wavelengths of 780nm and 850nm of laser, into the cerebral cortex. Participants will undergo a one-time functional near-infrared spectroscopy (fNIRS) procedure to measure cerebral hemodynamic patterns. * Resting-State Measurement: 5-10 min resting-state scans. * Task-Based Measurement: Participants will be shown an instruction video. Participants will complete a Verbal Fluency Task (VFT) during the fNIRS scan (15-20 min). * During the fNIRS scan, optional basic vital signs will be measured using respiratory belts, photoplethysmography (PPG), and electrocardiogram (ECG). * Each participant will complete 3 sets of resting-state and task-based measurements. Total estimated time for fNIRS assessment: 45-60 min.
Changes in oxyhemoglobin
Changes in oxyhemoglobin will be measured with a functional near-infrared spectroscopy (fNIRS) device by radiating a near light beam, at two wavelengths of 780nm and 850nm of laser, into the cerebral cortex. Oxyhemoglobin results are reported as a percentage of oxygen-bound hemoglobin compared to the total hemoglobin in the blood.
Time frame: Baseline, 60 minutes
Hamilton Depression Rating Scale (HAM-D)
A clinician-administered tool revaluating depression severity. The 17-item version assesses symptoms such as depressed mood, insomnia, and somatic complaints. Each item is scored on a 3- or 5-point scale, resulting in total scores that range from 0 to 52, with scores of 0-7 considered normal, 8-16 indicating mild depression, 17-23 moderate depression, and 24 or greater severe depression.
Time frame: Baseline
Young Mania Rating Scale (YMRS)
A clinician-rated scale administered to measure the severity of manic symptoms in participants diagnosed with bipolar disorder (during manic or hypomanic episodes). It includes 11 items assessing areas such as elevated mood, irritability, and hyperactivity. Each item is scored on a scale of 0 to 4 or 0 to 8, with total scores ranging from 0 to 60. Severity thresholds include no significant symptoms (≤12), mild mania (13-20), moderate mania (21-35), and severe mania (\>35).
Time frame: Baseline
Clinical Global Impression-Bipolar (CGI-BP)
A clinician-rated measure that provides a global assessment of illness severity, improvement, and therapeutic response in individuals with bipolar disorder. It includes separate ratings for mania, depression, and overall illness on a 7-point scale, where 1 indicates "normal, not at all ill" and 7 indicates "among the most severely ill."
Time frame: Baseline
Mini-Mental State Examination (MMSE)
The Mini-Mental State Examination is used to assess domains such as orientation, attention, memory, language, and visuospatial skills. It has a maximum score of 30, with lower scores indicating greater cognitive impairment. Scores are typically categorized as no cognitive impairment (24-30), mild cognitive impairment (18-23), and severe cognitive impairment (0-17).
Time frame: Baseline
Patient Health Questionnaire-9 (PHQ-9)
The PHQ-9 is a self-report questionnaire used to measure the severity of depressive symptoms over the past two weeks. This questionnaire is used in our clinical practice and will be collected from patient only if not already completed. It consists of nine items, each scored on a scale from 0 ("Not at all") to 3 ("Nearly every day"), with total scores ranging from 0 to 27. Higher scores indicate greater symptom severity, categorized as minimal (0-4), mild (5-9), moderate (10-14), moderately severe (15-19), and severe depression (20-27).
Time frame: Baseline
Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Neuropsychological Battery
The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) is a standardized cognitive assessment tool designed to evaluate cognitive decline, particularly in Alzheimer's disease (AD) and mild cognitive impairment (MCI). It includes measures of verbal fluency, word list learning, delayed recall, recognition memory, constructional praxis, and global cognition. The battery incorporates a 15-item abbreviation of the Boston Naming Task (J2) and a slightly modified version of the MMSE that does not use serial 7s (J3).
Time frame: Baseline
Plan to share: No
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.