The Safe and Sound Protocol (SSP) is a passive acoustic intervention that is designed as a "neural exercise" to promote efficient regulation of autonomic state. Prior research has shown that the SSP can improve autonomic function, auditory hypersensitivities, and emotion regulation in individuals with Autism Spectrum Disorders. This observational pilot study is being conducted to establish methods for an upcoming randomized controlled trial to test the utility of the SSP for trauma treatment.

This study will enroll clients at the Spencer Psychology clinic who are set to take part in SSP under the supervision of their therapist. Because the therapists have participated in the design of the protocol and will participate in data collection and analysis, SSP will be considered a research procedure. In addition to taking part in SSP, subjects complete a set of questionnaires and have their pulse measured before starting the SSP intervention, after having completed 2/5 hours of the SSP, one week after completing all 5 hours of the SSP, and one month after completing the SSP intervention. The investigators will also pull relevant information from Spencer Psychology's medical records to document diagnosis, track client progress during study, and augment self-reported demographics. Clients who are receiving psychotherapy but not the SSP will be recruited as a comparison group.

SSP Intervention Arm:

Inclusion Criteria:

• Client at Spencer Psychology in Bloomington, Indiana
• Diagnosed with PTSD or trauma not otherwise specified
• Already have agreed with therapist to administer SSP as a part of therapy

Exclusion Criteria:

• Tinnitus or hearing loss
• Diagnosed with cardiac arrhythmia
• At high risk for 2019 novel coronavirus (COVID-19) complications based on Center for Disease Control (CDC) guidelines, unless vaccinated

Comparison (Treatment As Usual) Arm Additional Criteria:

Inclusion Criteria:

1. 18 years of age or older
2. Active psychotherapy client at Spencer Psychology
3. Diagnosis of PTSD or trauma not otherwise specified
4. Match range of PCL-5 baseline scores with treatment arm during screener survey

Exclusion criteria:

1. Currently using or have previously used the Safe and Sound Protocol (SSP) in therapy
2. Current therapy includes Eye Movement Desensitization and Reprocessing (EMDR)

Researchers interested in using IPD collected or generated as part of this study may do so by contacting the study PI. Researchers will be asked to complete a Data Use Request Form, which includes contact information, description of the research project for which the data and/or code would be used, specification of which data and/or code would be needed for their proposed project, an approximate time line for their proposed project, and authorship on their proposed project.

Starting 6 months after publication of primary results

All requests for data will be reviewed by the PIs and co-Is and a majority vote will be used to determine whether the request is approved or not. If the request is approved, Dr. Kolacz will inform the requestor, return a signed copy of the completed Data Use Request Form to the requestor, and let the requestor know that written IRB approval of the requestor's proposed study from the requestor's home institution will be required before data and/or code will be shared with the requestor. If a request is approved pending revision to the Data Use Request Form, Dr. Kolacz will work with requestors to revise sections of their Data Use Request Forms in order to obtain approval. If the request is not approved, Dr. Kolacz will inform the requestor and returned a signed copy of the completed Data Use Request Form to the requestor that includes an explanation for the denial.

Adverse events were tracked over the course of participation in the study (SSP+Psychotherapy Median Length = 145 days, Control Arm Median length = 122 days)

Adverse Events were monitored/assessed without regard to the specific Adverse Event Terms