Transcutaneous Vagal Nerve Stimulation in Veterans With Posttraumatic Stress Disorder

Inclusion Criteria:

* Veterans between the ages of 18 and 75 will be included with a diagnosis of PTSD based on DSM-5 criteria

Exclusion Criteria:

Subjects will be excluded with:

* a history of mild traumatic brain injury (mTBI) based on VA Criteria
* moderate or greater TBI
* positive pregnancy test
* meningitis or other neurological disorder
* alcohol or substance abuse use disorder based on DSM-5 criteria within the past 12 months
* current or lifetime history of schizophrenia, schizoaffective disorder, bipolar I disorder, anorexia nervosa or bulimia, based on DSM-5
* active suicidal ideation with a plan
* a history of serious medical or neurological illness, such as cardiovascular, gastrointestinal, hepatic, renal, neurologic or other systemic illness that would preclude participation based on clinical judgment of the PI
* active opiate or benzodiazepine treatment
* history of structural abnormality on brain MRI or CT if one has been performed in the past