Photobiomodulation therapy (PBMT) uses light to influence the mitochondria of cells. PBMT of the brain enhances the metabolic capacity of neurons and stimulates anti-inflammatory, anti-apoptotic, and antioxidant responses, as well as neurogenesis and synaptogenesis. Its therapeutic role in disorders such as dementia and Parkinson's disease, as well as to treat stroke, brain trauma, and depression has gained increasing interest.

BioFlex is a form of PBMT consisting of light-emitting diodes (LEDs) and laser diodes. BioFlex utilizes red and near infrared light which penetrates tissues up to a certain tissue depth and studies have shown stimulates tissue growth and repair at the cellular level. PBMT has been proven useful for the treatment of soft tissue pain. Several studies have shown benefit in using PBMT in the treatment of certain neurological conditions, including chronic, mild traumatic brain injury (mTBI).

The purpose of this exploratory investigation, therefore, is to examine efficacy of BioFlex laser therapy on measures of brain function in patients suffering from PCS after mild-moderate, closed-head, traumatic brain injury cases.

Inclusion Criteria:

1. Male or female, at least 19 years of age or older
2. Diagnosis of persistent post-concussional syndrome after ≥3 months of traumatic brain injury, based on the ICD-10 criteria. This diagnosis should be given to the patient from a clinical practitioner. ICD-10 clinical criteria require a history of TBI and the presence of three or more of the following eight symptoms: 1) headache, 2) dizziness, 3) fatigue, 4) irritability, 5) insomnia, 6) concentration or 7) memory difficulty, and 8) intolerance of stress, emotion, or alcohol.
3. Current pharmacologic management can remain stable throughout the protocol.
4. Fluent in English
5. Able to understand the informed consent form, study procedures and willing to participate in study.

Exclusion Criteria:

1. Malignant skin carcinoma within the treatment area (neck and cranium)
2. Intake of photosensitizing medication.
3. Prior history of PBMT therapy
4. Current diagnosis of severe anxiety (or score of ≥15 on the GAD-7), severe depression (or score of ≥20 on the PHQ-9), schizophrenia or bipolar disorder
5. History of other major neurological disorder (brain cancer, dementia, multiple sclerosis, stroke)
6. Diagnosed epilepsy or history of seizures not effectively controlled by medications
7. Exposed to an investigational drug or device 30 days prior to starting the study, or concurrent use of an investigational drug or device while enrolled in the study
8. Pregnant, suspected to be pregnant or planning to become pregnant during the study
9. Contraindicated for the NeuroCatch® Platform 2, including:

9.1. Requires the use of hearing aids or a cochlear implant 9.2. Diagnosed with tinnitus that is currently active 9.3. Has temporary damage to hearing (e.g. punctured ear drum) 9.4. Unable to detect a 740Hz tone played at 85dB in both ears. 9.5. Implanted pacemaker or implanted electrical stimulators 9.6. Metal or plastic implants in the skull, excluding dental/facial implants 9.7. Unhealthy scalp (apparent open wounds and/or bruised or weakened skin) 9.8. Previous exposure to the NeuroCatch® Platform 2 audio sequences in the last 3 months

Study participants will be blinded to the PBMT treatment regimen they will receive. Participants will wear opaque goggles to blind them from seeing any light emitted from the LED arrays.

A trained laser technician will provide treatment to the study participants. The laser clinician will be unblinded to the participant's treatment allocation. Assessments will be performed by an independent blinded assessor.