The goal of this study is to determine how non-invasive brain stimulation (delivered through the ear called vagus nerve stimulation) affects fear learning processes in people who have experienced psychological trauma. To answer these questions, we measure bodily responses (heart rate, sweat, startle) and questionnaires. The main questions it aims to answer are:

Does non-invasive vagus nerve stimulation help reduce anxious arousal? Does non-invasive vagus nerve stimulation help dampen learned fear?

This study aims to determine how non-invasive brain stimulation (delivered through the ear) affects learning processes. During this study, participants who have experienced a trauma will be asked to complete surveys and come to the lab for about 7 hours across four lab visits. Researchers will measure body responses (heart rate, skin conductance, startle), while the ear is stimulated. Participants also will be asked to complete a startle task. The study is at the Wayne State University Tolan Park Research Clinic. Participants will be compensated for their time. To be eligible, participants must be 18-70 years old, have experienced or witnessed a traumatic event, be able to commit 7 hours of time to the study, and be able to wear sensors on their hands, arms, and head and sit quietly at a computer.

Aim 1. Establish feasibility and acceptability of taVNS in a diverse sample of Detroit metro residents with symptoms of posttraumatic stress. It is hypothesized that taVNS delivery will be feasible and acceptable for individuals with trauma exposure and PTS symptoms, and that there will be no difference in acceptability/tolerability between the active and sham conditions.

Aim 2. Establish the effects of active versus sham taVNS on physiological indicators during fear extinction. It is hypothesized that active compared to sham taVNS will a) result in facilitation of fear extinction, and b) show greater modulation of physiological responding. Exploratory Aim: Data will be explored for individual differences (affective blunting, hyperarousal, impaired discrimination of conditioned stimuli) which moderate taVNS effects.

This proposed project will determine how taVNS delivered at higher doses than have been previously administered influence the course of adaptive posttraumatic processing in a sample with trauma exposure, while evaluating the psychophysiological profile in multiple contexts.

Inclusion Criteria:

1. Ages 18-80
2. Fluent in English
3. Experience with a DSM-5 Criterion A trauma (LEC-5)
4. Probable PTSD (PCL-5 ≥ 32)

Exclusion Criteria:

1. Visual or Auditory impairment
2. Major injury at time of screen or study procedures
3. Taking ≥20 mg morphine per day
4. Current substance use or intoxication (12-panel drug test)
5. Intellectual disability (MoCA)
6. Self-inflicted injury
7. Occupational injury
8. Prisoner
9. Ongoing domestic violence
10. Pregnant or breastfeeding
11. Contraindications for taVNS

A. Types and amount of scientific data expected to be generated in the project:

Demographic, end user feedback, clinical (self-report surveys), and physiological data will be collected from 60 individuals with PTSD. Data will be collected, processed, and then shared at the individual level. All data will be de-identified prior to uploading to the repository. However, sufficient information necessary for generating a global unique identifier (GUID) for the NIMH data archive (NDA) will be collected for each subject.

B. Scientific data that will be preserved and shared, and the rationale for doing so: Scored assessments and self-report surveys will be shared to the NDA, as well as scored physiology measures. Individual, item-level scores, may result in identification of participants, and will not be shared. Any potentially identifiable PHI will be removed from data sets.

C.Study protocols, data collection instruments, data processing and scoring protocols, and syntax for data analysis.

A. All data will be deposited to the NIMH data archive (NDA) 12 months after the study begins and will be deposited biannually following the first submission.

B. Within the first 6 months of an NDA Data Submission agreement will be submitted by the PI through the NDA website, which will allow for access to the NDA Collection page where data will be submitted. The NCT# will be submitted within this agreement. Data will be findable for the research community using the NDA Collection page. An NDA study will be created for each publication and each study will be assigned a digital object identifier (DOI). The DOI will be referenced in the publication so that the research community can access the data used in the publication. C. The research community will have access 1-2 years after study end date. Publication will be linked to a study containing the data used in that publication and may be found using the DOI when the pre-print is available. NDA will determine data preservation duration.

NDA will control data access. Researchers will submit a data access request for broad use and must be sponsored by an NIH recognized institution and have a research-related need to access the data. The NDA data access committee will make final determination on which requests to grant.