Closed Loop Vagal Nerve Stimulation for Patients With Posttraumatic Stress Disorder

Closed Loop Vagal Nerve Stimulation in Patients With Posttraumatic Stress Disorder

The tasks of the project are to map the potency and kinetics of the neurologic, autonomic peripheral, inflammatory, and behavioral responses to vagal nerve stimulation (VNS) vs. sham treatment, at baseline and in response to stressful traumatic scripts related to personal traumatic events, as well as a series of other stressors.

The purpose of this project is to develop the fundamental physiological understanding of feedback controlled vagal nerve stimulation (VNS) using positron emission tomography (PET) brain imaging and blood biomarker measurement with stress in healthy individuals and individuals with PTSD. Healthy human subjects with a history of psychological trauma but without the diagnosis of a psychiatric disorder (Phase 1), and human subjects with a history of PTSD (Phase 2), undergo PET imaging of the brain in conjunction with VNS or a sham treatment during exposure to neutral scripts and scripts of personal traumatic events. Blood is drawn simultaneously for measurement of a variety of stress responsive biomarkers, including inflammatory markers and neurohormones. A second PET scan with biomarkers assesses the delayed effects of VNS. On two other days subjects undergo exposure to random stressors with VNS or sham in conjunction with measurement of stress biomarkers.

Inclusion Criteria:

Phase 1:

• Do not meet criteria for post traumatic stress disorder (PTSD) or other major mental disorder as determined by the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5 SCID) interview for PTSD
• Have a history of psychological trauma as defined by DSM-5.

Phase 2:

- Meet criteria for PTSD as determined by the Structured Clinical Interview for DSM-5 (SCID) interview for PTSD.

Exclusion Criteria:

• Positive pregnancy test
• Meningitis
• Traumatic brain injury
• Neurological disorder or organic mental disorder
• History of loss of consciousness greater than one minute
• Alcohol abuse or substance abuse or dependence based on the SCID within the past 12 months
• Positive toxicology screen
• Current or lifetime history of schizophrenia, schizoaffective disorder, or bulimia, based on the SCID
• A history of serious medical or neurological illness, such as cardiovascular, gastrointestinal, hepatic, renal, neurologic or other systemic illness
• Evidence of a major medical or neurological illness on physical examination or as a result of laboratory studies (complete blood count (CBC), blood urea nitrogen (BUN), creatinine, blood sugar, electrolytes, liver and thyroid function tests, urinalysis, and EKG)
• Active implantable device (i.e. pacemaker)
• Carotid atherosclerosis
• Cervical vagotomy