Mild cognitive impairment (MCI) is a transitional risk state that occurs between the normal aging process and Alzheimer's dementia (AD). On average 32% of patients with MCI will progress to dementia, 62% will stay stable, and about 6% will return to normal cognition at subsequent visits.

Current treatment for MCI includes cholinesterase inhibitors (donepezil, galantamine and rivastigmine), and NMDA receptor antagonists (memantine) which delay or slow the worsening of symptoms and treat cognitive symptoms (memory loss, confusion, and problems with thinking and reasoning). Despite currently ongoing drug studies and modest clinical benefits of currently approved drug treatments, there continues to remain a need for treatments for long term symptomatic improvement of MCI with fewer and less severe side effects.

Photobiomodulation (PBM) therapy also called low-level laser (or light) therapy (LLLT) is a safe, non-invasive, non-thermal (no significant heat is generated) method of therapy which uses either visible red or near-infrared (NIR) light to stimulate, heal and repair damaged or dying tissue cells. This study proposes to use the Neuro RX Gamma device (version 2) to deliver NIR light energy to particular brain regions which are dysfunctional in MCI participants.

This study will recruit approximately 60 participants with MCI for the study, and the total expected duration of the participant's participation in the study is 12 weeks. The active and sham Neuro RX gamma device (v2) consists of a headset with a built-in controller and nasal applicator. The nasal applicator contains a single LED and will be placed into the nostril and clipped into place. The headset is a wearable applicator that may be adjusted. It consists of 5 LEDs. A red star symbol identifies the front of the headset and helps the user orientate the headset on the head. LEDs are semiconductor electronic components that emit light.

Inclusion Criteria:

Individuals who meet the criteria for MCI of 1) cognitive concern by the subject, informant, or clinician; 2) Montreal Cognitive Assessment (MoCA) score between 19-25 and impairment in learning and memory domain; 3) essentially normal functional activities as derived from the Clinical Dementia Rating Scale (CDR) and 4) the National Institute on Aging and Alzheimer's Association (NIA-AA) criteria for MCI due to Alzheimer's disease. , Age is greater than or equal to 50 years old. Meets the National Institute on Aging and Alzheimer's Association (NIA-AA) criteria for MCI due to Alzheimer's disease.

Essentially normal functional activities as derived from the CDR. If receiving ongoing cholinesterase inhibitor therapy and/or memantine, must be on a stable dosage for at least the prior 3 months.

MoCA score between 19 and 25 at screening assessment and impairment in learning and memory domain.

Exclusion Criteria:

Cannot tolerate blood draws. Claustrophobia (fear of small or enclosed spaces), that cannot tolerate MRI scanners*.

A pace-maker or other metal implants that would preclude safe use of MRI*. DSM 5 diagnosis of alcohol or other substance use disorders within the past 12 months.

Unstable medical illness, (e.g., uncontrolled diabetes mellitus or hypertension).

Any history of stroke, seizures, MS, or Lyme disease. Any issues with ambulation, vision, or hearing which could, in the opinion of the investigator, interfere with their ability to complete assessments.

Participant does not speak English at a level necessary for the completion of the assessments.

Has not completed at least a grade eight education, as necessary for the completion of the assessments.

Currently participating in another clinical research study involving an investigational product.

History of significant agitation and/or aggression, epileptic seizures. Current neurologic disease affecting cognition other than Alzheimer's disease. Photosensitivity reactions to sunlight or visible light (polymorphous light eruption, solar urticaria, persistent light reactivity).

History of recurrent epistaxis within the last 24 weeks or currently taking major anti-coagulants (including warfarin, low molecular weight heparin) Increased skin sensitivity at the treatment site including active herpes simplex in the treatment area, history of keloid formation, or history of retinoid use in the past month.

Pregnant or lactating or planning to become pregnant. Currently undergoing infrared light therapy treatment. Any reason that, in the opinion of the investigator, might place a participant at unacceptable risk for participation in the trial.

Note: *Participants with contraindications for MRI can still enroll in the trial and participate without undergoing the MRI procedure. However, if participants do not have contraindications, undergoing the MRI is required as part of the trial.

To ensure balanced allocation across trial groups, the trial will employ a block randomization method with a block size of 4. This method generates balanced combinations (TTCC, TCTC, TCCT, CTTC, CTCT, CCTT), from which blocks will be randomly selected to assign the 60 participants evenly, with 30 participants per group. Randomization will be performed using a computer-generated process, and an independent Research Assistant will manage this to maintain blinding for participants, study investigators, and data analysts. Unblinding will occur only in the case of patient emergencies or at the end of the trial. This approach ensures that each participant is assigned to either the sham or active treatment group in a 1:1 ratio, while maintaining the integrity of the trial and reducing potential biases.