History of shrapnel or other foreign bodies which would preclude MRI scanning

Meningitis

Traumatic brain injury

Neurological disorder or organic mental disorder

History of loss of consciousness

Current or lifetime history of alcohol abuse or substance abuse or dependence base on the SCID

Current or lifetime history of schizophrenia, schizoaffective disorder, or bulimia based on the SCID

History of serious medical or neurological illness, such as cardiovascular, gastrointestinal, hepatic, renal, neurologic or other systemic illness

Evidence of a major or neurological illness on physical examination or as a result of laboratory studies

positive urine toxicology screen

Current steroid use

Norepinephrine Transporter Availability in PTSD