Appliance of Heart Rate Variability Biofeedback in Acceptance and Commitment Therapy: A Pilot Study

Mindfulness, defined as a fourfold process consisting of being present with aversive experiences, accepting their aversive content, focusing on the observing perspective, and creating a distinction between content of private experiences and behavior, is an essential part of the so-called third wave behavior therapies, such as Acceptance and Commitment Therapy (ACT). Besides being a behavioral intervention and an important theoretical construct, training mindfulness has been shown to change brain structures and neuronal functioning. In this article the effects and processes of an integrative approach in which heart rate variability (HRV) biofeedback combined with ACT is investigated. Seven clients who were referred to an outpatient facility filled out mindfulness questionnaires (Mindful Attention Awareness Scale) prior and after mindfulness-based HRV biofeedback. In addition mean weighted HRV scores were computed before, during, and after training. Finally, qualitative analyses were performed to investigate specific client-trainer interactions during training as well as subjective training effects and eventual problems resulting from the training. Qualitative and quantitative results were as expected in predefined hypotheses, indicating that HRV training may be an effective way to train the clients' abilities to increase their amounts of HRV and increasing their mindfulness skills. The relationship between HRV as a biological marker and mindfulness are discussed along with the clinical implications of this integrative approach.