Respiratory Training in the Treatment of Transdiagnostic Pathological Anxiety

Inclusion Criteria: 1. Clinically elevated anxiety as indicated by an eight or higher on the Overall Anxiety Severity and Impairment Scale (OASIS). 2. Meets DSM-5 criteria for one or more of the following anxiety or trauma-related disorders as their "primary" mental disorder: * Generalized Anxiety Disorder * Panic Disorder * Health Anxiety * Agoraphobia * Social Anxiety Disorder * Posttraumatic Stress Disorder * Acute Stress Disorder * Adjustment Disorder with primary anxious mood * Anxiety disorder not otherwise specified 3. No current use of psychotropic medications or stable on current medications for at least 6 weeks 4. Age 18+. 5. Able to arrange transportation to our laboratory for study appointments. 6. Fluent in English. Exclusion Criteria: 1. No history of medical conditions that would contraindicate participation in fear-provocation or respiratory challenges, including: * Cardiovascular or respiratory disorders * High blood pressure * Epilepsy * Strokes * Seizures * History of fainting * Pregnant or lactating 2. Not currently receiving other psychological treatment for anxiety. 3. No history of a suicide attempt within the past 6 months. 4. No history of psychosis within the past 6 months. 5. No history of moderate to severe alcohol or substance use disorder (with the exception of nicotine) within the past 3 months. 6. Does not endorse COVID-19 symptoms during the screening phase.