Non-Invasive Vagus Nerve Stimulation as a Probe to Map Functional Connectivity in Schizophrenia Using Functional Magnetic Resonance Imaging

Prior treatment

• Being treated with one of the following medications: benzodiazepines or other CNS depressants.
• Patients with prior exposure to VNS therapy whether using an implantable or external device
• An active implantable medical device, such as a pacemaker, hearing aid implant, or any implanted electronic device
• Patients who have had surgery to cut the vagus nerve in the neck (cervical vagotomy)

Other illness

• Evidence of alcohol or other substance use disorder in the past 3 months
• Diagnosis of other primary psychiatric disorder (defined in this case as being the main focus of treatment) as determined by the MINI, such as: bipolar disorder, personality disorders, post-traumatic stress disorder, obsessive-compulsive disorder, dissociative disorders, eating disorder, or cognitive deficits due to neurological conditions
• No clinically significant neurological disease based on medical history (e.g., epilepsy) or significant head injury.
• Any of the following disorders are exclusionary: Rheumatoid arthritis; Lupus erythematosus; Autoimmune hepatitis; Autoimmune peripheral neuropathy; Autoimmune pancreatitis; Behcet's disease; Crohn's disease; Autoimmune glomerulonephritis; Grave's disease; Guillain-Barre syndrome; Hashimoto's thyroiditis; Autoimmune polymyositis or polymyalgia; Myasthenia gravis; Narcolepsy; Polyarteritis nodosa; Scleroderma; Sjogren's syndrome; Transverse myelitis; Wegener's granulomatosis; History of seizures (only childhood febrile seizures are allowed)
• An open wound, rash, infection, swelling, cut, sore, drug patch, or surgical scar(s) on the neck at the treatment location
• Exclusion criteria for control subjects include any history of mental illness or psychotropic drug abuse.

Other

• Reported pregnancy and/or nursing. A participant may only take part if they are sexually abstinent or using a reliable method of birth control (birth control pills, Norplant, condoms and spermicide).
• Imminent suicide or homicide risk as determined by the investigator
• A metallic device, such as a stent, bone plate, or bone screw, implanted at or near the neck
• Patients diagnosed with narrowing of the arteries (carotid atherosclerosis)

• Age19-55 years old, inclusive
• Sufficient fluency in English to understand testing procedures and provide informed consent
• In one of these three diagnostic groups:
  • Schizophrenia Spectrum Disorder (SSD), which can include the diagnoses of Schizophrenia, Schizoaffective Disorder, Unspecified Schizophrenia Spectrum, Schizophreniform Disorder, Brief Psychotic Episode, or Psychotic Disorder NOS (as defined by DSM-V and determined by the Mini International Neuropsychiatric Interview (MINI)
  • Unipolar Major Depressive Disorder (MDD) of any subtype. Depressed participants will have a score of \>18 on the Montgomery Asberg Depression Rating Scale (MADRS), as defined by DSM-V and determined by the Mini International Neuropsychiatric Interview (MINI)
  • Normal healthy controls, individuals with no personal history of any Axis I disorder. Controls will have a MADRS score of \<7.