Subjective cognitive impairment (SCI) is a non-clinical condition manifesting as a self-reported decline in cognitive function without objective clinical evidence, and is prevalent among older adults and strongly associated with declining mood. This study explores the potential of photobiomodulation (PBM) as a therapeutic intervention for SCI. PBM, using near-infrared light, is a non-invasive neuromodulation approach that has shown promise in improving neuronal function, blood flow, and reducing inflammation in both healthy adults and patients with neurological conditions, including dementia and depression. This study proposes investigating the potential of forehead (tPBM), intranasal (iPBM) and vagal (vPBM) PBM to enhance mood and cognitive function in individuals with SCI as a proof of concept for the future use of PBM as therapy for cognitive decline in general.
This study will recruit approximately 80 participants with SCI for the study, and the total expected duration of the participant\'s participation in the study is 5 weeks. The active and sham Neuro 5T device consisting of a headset with a built-in controller, nasal and neck applicators will be used. The nasal and neck applicators each contains a single LED and will be placed into the nostril or neck and secured into place. The headset contains multiple LEDs in a wearable applicator and may be adjusted. The Neuro 5T also contains telemetry features to allow documentation of patient usage of the device. LEDs are semiconductor electronic components that emit light. Participants will be given PBM devices for in-home usage, 2 times a day, 7 days a week, for 5 weeks. Participants will undergo EEG, MRI, cognitive and nasal microbiome assessments before and after the 5-week period.