The Effect of Near-infrared Light Therapy on Brain Function and Cognition in Young and Older Adults

The goal of this pilot clinical trial is to test whether transcranial photobiomodulation (tPBM), a non-invasive brain stimulation technique using near-infrared light, can improve brain blood flow regulation (neurovascular coupling) and cognitive function in older adults. The main questions it aims to answer are: * Does tPBM enhance neurovascular coupling responses during memory and finger tapping tasks? * Are these improvements linked to better cognitive performance and lower levels of brain inflammation and oxidative stress? Researchers will compare an active tPBM treatment arm to a sham treatment arm to see if tPBM leads to measurable improvements in brain activity and cognitive function compared to no active stimulation. Participants will: * Receive either active tPBM or sham stimulation sessions for 4 weeks, every other day using a portable intervention device. * Complete questionnaires and an iPAD-based cognitive testing protocol * Complete memory and motor tasks while their brain activity is measured using non-invasive techniques: simultaneous functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG), transcranial doppler (TCD) flowmetry. * Retinal vessel reactivity will be measured during flickering light stimulus using a special camera (dynamic vessel analysis, DVA). * Provide blood samples to test for biomarkers of inflammation, oxidative stress and brain cell damage.

NCT Number	NCT07209683
Lead Sponsor	University of Oklahoma
Conditions	Cognition, Neurovascular Coupling Mechanism and Cognitive Function, Neurovascular Control, Brain Aging, Brain Activity
Enrollment	30 participants
Start Date	2025-10-01
Primary Completion	2026-09-30 (estimated)
Study Completion	2026-12-31 (estimated)
Updated on ClinicalTrials.gov	2026-02-06