Inclusion Criteria:  Male or female, at least 19 years of age or older A score of 33 or more on the Posttraumatic Stress Disorder Checklist (PCL-5) PTSD symptom duration of ≥ 12 months Stable dose of any medications for the last three months, with no changes anticipated for the duration of the study Adequate support at home (e.g., family member or caregiver) to ensure assistance in seeking access to help if needed Able to understand the informed consent form, study procedures and willing to participate in study Currently has a primary care provider  Exclusion Criteria:  History of substance dependence or abuse (within the last 3 months) Unstable psychosocial settings (homelessness, lack of support at home) Moderate to high risk of suicidal ideation or behaviour as measured by the Columbia Suicide Severity Rating Scale (C-SSRS) 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 Use of medications for PTSD within the last 6 weeks History of other major neurological disorder (brain cancer, dementia, multiple sclerosis, stroke) Detection of mild cognitive impairment (mini-ACE score of ≤ 25) Diagnosed epilepsy or history of seizures Not proficient in English Recent (within last 2 years) acquired brain injury 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 If female and of child-bearing potential: pregnant, suspected or planning to become pregnant or breast-feeding  Contraindicated for the NeuroCatchTM Platform, including:  13.1. Requires the use of hearing aids or a cochlear implant 13.2. Diagnosed with tinnitus that is currently active 13.3. Has temporary damage to earing (e.g. punctured ear drum) 13.4. Unable to detect a 740Hz tone played at 85dB in both ears. 13.5. Implanted pacemaker or implanted electrical stimulators 13.6. Metal or plastic implants in the skull, excluding dental/facial implants 13.7. Unhealthy scalp (apparent open wounds and/or bruised or weakened skin) 13.8. Previous exposure to the NeuroCatch™ Platform audio sequences in the last 3 months  Contraindicated for PoNSTM use, including:  14.1. Current disease or sensitivity of the oral cavity 14.2. History of oral cancer 14.3. Oral surgery within three months of screening 14.4. Oral cavity piercings that could interfere with PoNSTM use 14.5. Sensitivity to Nickel, Copper, or Gold 14.6. Currently enrolled in a PoNSTM treatment program or use of the PoNSTM device in the last 5 weeks 14.7. History of penetrating brain injuries 14.8. History of neurodegenerative diseases 14.9. Chronic infectious disease 14.10. Unmanaged hypertension 14.11. Diabetes 14.12. History of seizures