Many psychological treatment techniques require a great deal of faith on the part of the patient that it will actually serve its purpose. There is no guarantee, for example, that applying a new coping skill or behavioral technique will have any objective effect.
Fortunately, there is a way to provide such concrete assurance: biofeedback. There are several different types of this technique, which measures brain wave activity or other physiological responses like skin temperature, muscle tension, or heart rate variability (HRV) while patients make a purposeful attempt to influence these variables.
Research findings suggest that biofeedback may be effective in reducing symptoms related to numerous mental health issues, including obsessive-compulsive disorder,1 postpartum stress,2 attention-deficit/hyperactivity disorder,3 depression,4 post-traumatic stress disorder,5 and food cravings.6
HRV is a measure of the time intervals between heartbeats. High variability is generally desirable, while low variability is not because it means the heart is not adjusting in a dynamic way to varying demands, but instead is operating in a sort of autopilot mode. HRV is considered a window into one’s autonomic nervous system (ANS) functioning. Lower HRV reflects dominance of the sympathetic branch of the ANS, which governs the “fight or flight” reaction in response to a threat, while higher HRV is associated with dominance of the parasympathetic branch, which governs the “rest and digest” response that kicks in once the threat has passed.
In HRV biofeedback, patients learn how to influence their HRV by using slow, deep breathing to shift to parasympathetic dominance — essentially, they learn how to “switch on” the relaxation response.
“HRV biofeedback somehow ‘stimulates’ the vagus nerve, which primarily sends signals from the body to the brain,” Adrian Meule, PhD, a psychologist and post-doctoral research fellow at LWL University Hospital of Ruhr University Bochum in Germany, told Psychiatry Advisor. The vagus nerve has connections to the prefrontal cortex, which influences behavioral control, and to the limbic and paralimbic areas of the brain, which are related to emotional and reward processing.