The goal of this clinical trial is to learn if the addition of frequency filtered music (Safe and Sound Protocol) to daily cognitive processing therapy improves effectiveness for reducing PTSD symptoms. The main questions it aims to answer are:

• Does the addition of frequency filtered music reduce PTSD symptoms for patients receiving cognitive processing therapy for PTSD?
• Does the addition of frequency filtered music to cognitive processing therapy improve stress physiology (arousal)?
• Does improvement in physiological stress regulation help explain improvements in hyperarousal and PTSD symptoms? Researchers will compare the effects of a frequency filtered classical music playlist to an identical playlist without added filtering. Participants will be randomized to a music playlist.

Participants will:

• Receive 10 daily sessions of cognitive processing therapy
• Listen to 15 minutes of music before their therapy sessions (2.5 hours music listening total).
• Complete clinical interviews and questionnaires before, during, and up to 6 months after therapy.
• Have their physiological arousal monitored during listening and therapy sessions
• Wear a Fitbit device and complete smartphone surveys for 4 weeks

Inclusion Criteria:

• At least 18 years of age
• Meets diagnostic criteria for a) PTSD or b) subthreshold PTSD with hyperarousal (i.e., meets diagnostic threshold for 3 of 4 symptoms, one of which is hyperarousal)
• Ability to move between sitting to standing without assistance
• Ability to attend two weeks of daily in-person therapy sessions at either the Ohio State University or at the Wright-Patterson Air Force Base (WPAFB) Medical Center

Exclusion Criteria:

• Heart condition (such as cardiac arrhythmia) or pacemaker
• An allergy that would prevent wearing adhesive for durations of 2 hours or less
• Insufficient English fluency to fully engage in psychotherapy
• Use of hearing aids
• Current or prior tinnitus (persistent ringing or other noises in ears not caused by an external sound)
• Severe traumatic brain injury
• An ongoing stressor or condition deemed by the investigators to place the participant at risk for injury or a poor outcome (e.g., undergoing disability evaluation, undergoing a medical board evaluation to be medically discharged from the military, pending negative administrative or legal actions).
• Inability to complete the informed consent process due to the acute effects of a medical or psychiatric condition (e.g., intoxication, mania, psychosis)

Researchers interested in using IPD and/or computer code 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 and/or code use 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.