NCT06345859 · University of Southern California
Regulation of Affect and Physiology in Depression
(RAPID)
What this study is about
Although treatments for depression are effective for many people, not everyone responds to treatment. This lack of treatment response could be due, in part, to the presence of multiple underlying causes of people's depression.
View original scientific description
Although treatments for depression are effective for many people, not everyone responds to treatment. This lack of treatment response could be due, in part, to the presence of multiple underlying causes of people's depression. This study aims to identify subtypes of depression, based on two factors: how successful people perceive themselves to be at regulating their affect in everyday life; and how much activity in the parasympathetic nervous system increases during moments when people try to regulate. The study involves ambulatory assessment of affect, regulation strategies, and physiological activity in everyday life, in a sample of young adults with remitted major depressive disorder and healthy volunteers. We will study regulation responses in the lab to further determine how subtypes differ in neural, physiological, and behavioral responses. Finally, participants will be randomly assigned to a remote, self-administered biofeedback intervention (vs. control intervention) designed to increase parasympathetic activity and physiological regulation success. While engaging in biofeedback at home for 10 days, participants will simultaneously repeat the ambulatory assessments. This design will allow us to determine the proximal impact of biofeedback on indices of regulation success in everyday life, and whether biofeedback has differential impact on regulation success for different subtypes.
Interventions
BEHAVIORAL
Heart rate variability biofeedback
This is a Phase 2 parallel intervention design with random assignment. We will randomly assign participants to one of two biofeedback conditions. Both conditions involve completing breathing exercises at home, 30 minutes per day for 10 days, while receiving continuous feedback about parasympathetic activity from the computer.
Primary outcome measures
Physiological regulation success
Time frame: The two 10-day ambulatory assessment periods.
A slope representing the strength of the relationship between how much each individual's heart rate variability increases after engaging in adaptive regulation strategies (reappraisal, distraction, and/or acceptance). Values of this variable during the 10-day biofeedback intervention period will be compared to values during the 10-day baseline ambulatory assessment periods.
Average level of heart rate variability
Time frame: The two 10-day ambulatory assessment periods.
An intercept representing the average level of heart rate variability each person experienced. Values of this variable during the 10-day biofeedback intervention period will be compared to values during the 10-day baseline ambulatory assessment periods.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- for Participants with Remitted Depression:
- Meeting criteria for lifetime major depressive disorder.
- Currently meeting criteria for full remission (absence of clinically significant symptoms) for at least eight weeks, and having a Hamilton Depression Rating Scale score of less than or equal to 7. Inclusion Criteria for Healthy Volunteer Participants:
- No lifetime history of any psychiatric disorder.
- No first-degree relatives with a mood disorder.
Exclusion criteria
- (same for all participants):
- Change in psychotropic medication use within the last 30 days
- Autism spectrum disorder
- Current eating disorder
- Intellectual disability
- Substance use disorder within the past 6 months
- Contraindications for magnetic resonance imaging or electrocardiogram assessment (e.g., presence of metal in body, claustrophobia, cardiac device, pregnancy).
Where
- Los Angeles, California
Collaborators
National Institute of Mental Health (NIMH)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 4, 2026 · Source of record for eligibility and locations