Can a neck injection quiet the Brain's fear response in PTSD?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. 18-65 years of age 2. Chronic (at least one month post-trauma) DSM-5 PTSD symptoms 3. CAPS-5 Past Month score ≥ 26 4. Meets current DSM-5 PTSD diagnosis 5. Stable medications for 3 or more months by the time of study entrance (with the exception of benzodiazepines) 6. Willing and able to provide informed consent Exclusion Criteria: 1. History of stellate ganglion block treatment 2. Allergy to local anesthetics (e.g. ropivacaine, bupivacaine) 3. Allergy to iodinated contrast agents 4. Diagnosis of bipolar I disorder with a past year manic episode 5. Diagnosis of a psychotic disorder or psychotic symptoms 6. Diagnosis of current moderate or severe substance use disorder 7. History of neurological disease (that involves the brain), seizure, or significant head trauma (i.e., extended loss of consciousness, neurological sequelae, or known structural brain lesion) 8. Significant recent suicidal ideation or significant suicidal behavior in the past 12 months or suicidal ideation with imminent risk that warrants a higher level of care 9. Concurrent trauma focused psychotherapy 10. Pregnancy (to be ruled out by urine ß-HCG) 11. Metallic implants or devices contraindicating magnetic resonance imaging by interfering with patient safety or fMRI data collection; cases will be cleared by the Principal Investigator and Center for Brain Imaging 12. Morbid obesity (BMI \>4 kg/m2) 13. Current use of opioids, cocaine, or benzodiazepines (as assessed by urine toxicology) 14. Self-injurious behavior that involves suicidal intent, requires medical attention, or occurs daily. 15. Cardiac conditions or any prior heart surgeries 16. Respiratory conditions such as COPD or untreated asthma 17. History of heavy metal poisoning 18. History of neck or throat surgeries 19. Vocal cord problems or paralysis 20. Untreated high blood pressure 21. Current cancer diagnosis 22. Diagnosis of Guillain-Barré syndrome 23. Diagnosis of Parkinson's Disease 24. Unable to take 7 days off of blood thinners