Study had IRB approval from VA and began in late Feb 2020, did not enroll any participants before paused during the COVID. Final permissions from VA to restart recruitment was never received and therefore was withdrawn.

This study will examine the effects of psychotherapy as treatment for PTSD. This research will see how brain activity and brain connectivity is affected by Mindfulness Based Cognitive Therapy (MBCT) and Muscle Relaxation Therapy (MRT). Participants that qualify to be in this study will receive 8 weeks of group therapy in MBCT or MRT. Prior to receiving therapy participants will: complete baseline assessments related to their PTSD; fill out surveys; have an functional magnetic resonance imaging (fMRI); and provide a saliva sample. These assessments will be repeated after the therapy is over. Overall study participation should last approximately 10-12 weeks.

Note: due to COVID precautions, treatment shifted from in-person to remote ("Zoom" videoconferencing)

Inclusion Criteria:

• Meets current Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) criteria for PTSD (with or without Major Depressive Disorder) or subsyndromal PTSD (qualifying trauma, and at least one intrusive, one avoidant, one negativity, and one arousal symptoms, and significant impairment or distress); type of trauma shall include interpersonal violence - combat, physical assault, sexual assault, etc.

Exclusion Criteria:

• Dissociative PTSD
• Delayed-onset PTSD
• Magnetic Resonance Imaging (MRI) contraindications (e.g. metal in body, inability to be in the scanner - claustrophobia, severe back pain, etc.)
• Serious medical or neurologic conditions (e.g. stroke, seizures)
• Suicide risk
• Psychosis
• Life history of schizophrenia
• Life history of bipolar disorder
• Current severe substance use disorder
• Other factors that preclude safe and meaningful participation in the study, at discretion of the PI and study team

We plan to make available data from fMRI scans from human subjects initially to collaborators for independent replication / data pooling. We also plan to make the de-identified brain scans available to the broad scientific community, however, additional redaction steps may need to be made to brain scans to ensure subject confidentiality / inability to identify individuals from brain scans. Completely de-identified research data (redacted according to NIH practice to prevent disclosure of personal identifiers) which documents the research findings will be made available after the main findings from the finalized research dataset have been accepted for publication. And with approval of Dept Veterans Affairs Office of Research and Development.

Within 36 months of completion of the project.

Access to data generated by the project will be available for educational, research and non-profit purposes to researchers who provide a methodologically sound proposal. Data generated under this project will be administered in accordance with NIH Sharing policies, including NIH Policy on Dissemination of NIH-Funded Clinical Trial Information (8/2016), and the NIH Grants Policy Statement (Availability of Research Results) (11/2015). Depending on such NIH policies, Data generated by this project may be available for educational, research or non-commercial purposes under the terms of a data use agreement. Data will be stored in an established data repository (e.g. Inter-university Consortium for Political and Social Research (ICPSR): icpsr.umich.edu) with appropriate provisions for curation and longterm preservation.

Statistician will not know the group assignment until blind is broken. Statistician randomizes the groups. Principal investigator will not know group assignment until blind is broken.