Abstract
This review examines what constitutes heart rate variability (HRV), the relationship between HRV and the autonomic nervous system, and the physiology driving HRV. HRV is correlated with vagal nerve activity and parasympathetic nervous activation. Higher HRV is correlated with youth, active lifestyle, adaptive capacity, and good health. Next, the review examines the medical significance of HRV, especially the correlation between lower HRV and the presence of medical and psychological disorders. In general, HRV serves as a biomarker for health and disease, an index of autonomic nervous system dysregulation, an index of prefrontal cortical functionality, and a marker for psychopathology across diagnoses. Higher HRV is associated with several characteristics associated with successful psychotherapy and hypnotherapy: social engagement, compassion, emotional regulation, and cognitive flexibility. Given this association, somatic regulation should be regarded as integral to treatment alongside psychotherapy and hypnosis. Understanding HRV can enable the psychotherapist and hypnotherapist to optimize treatment. In effect, the therapist can harness the power of the brain and nervous system to better prepare the patient for therapy and to enhance the process of therapy. This review encourages therapists to utilize several strategies and interventions to increase patients' HRV levels prior to and during therapy. The review will be most applicable for those hypnotherapists who integrate hypnosis into counseling and psychotherapy. The review describes the process by which HRV biofeedback training guides the individual to voluntarily increase HRV. It also identifies a number of lifestyle parameters and self-care practices (including self-hypnosis) that increase HRV. Encouraging lifestyle and self-care practices to increase HRV can support a greater response to hypnotherapy and psychotherapy. With additional training, hypnotherapists can integrate HRV biofeedback into a hypnosis practice. Further, several simple interventions already within the scope of most hypnosis practitioners can be utilized to enhance HRV at the beginning of a hypnotherapy process, and again during the process of therapy.