Rollin McCraty and Robert A. Rees
Institute of HeartMathModern biofeedback generally involves recording and displaying physiological signals which provide indicators of automatic physiological functions that normally occur outside our conscious awareness. Listening to, learning from and control- ling physical processes normally considered automatic are practices that in either primitive or sophisticated form are found in many, especially spiritual, traditions, including Eastern yogic practices. In its broadest sense, biofeedback is something practiced by nearly everyone. Looking at oneself in a mirror, taking one’s tem- perature, stepping on a scale, or having an awareness of some undetected illness may all be forms of biofeedback. The idea of providing such feedback to help people improve their ability to self-regulate psychological or bodily functions had its origins in the late nineteenth and early twentieth centuries. However, it did not emerge as a field of serious scientific investigation and therapeutic practice until the 1970s and 1980s. At present, biofeedback as a mode of complementary and alter- native medicine is widely used in both medical and psychotherapeutic practice.
In medicine, biofeedback techniques are used for such things as digestive system disorders, headaches, high and low blood pressure, epilepsy, cardiac arrhythmias,
Biofeedback 103 incontinency, and certain movement disorders. In psychotherapy it is used to deal with various psychiatric conditions (e.g., panic, anxiety, obsessive-compulsive disorders, and various phobias), to reduce stress, and to induce relaxation. These techniques work by helping patients become conscious of and control patterns of physiological functioning.
Types of biofeedback instrumentation include skin conductance levels (SCL), peripheral skin temperature, electromyogram (EMG), electroencephalography (EEG), heart rate (HR), and, more recently, heart-rate variability (HRV). Such procedures and the development of new instrumentation may provide even more subtle and sophisticated means of detecting, modulating and controlling physio- logical functions, thereby improving the quality of life.
The type of biofeedback that is currently being used in the widest variety of applications is HRV and HRV coherence feedback. As a noninvasive measure of neurocardiac function that reflects heart-brain interactions and autonomic nervous system (ANS) dynamics, HRV monitoring is an effective biofeedback modality because it provides a reliable measure of autonomic nervous system dynamics that is particularly sensitive to changes in psychophysiological states.
HRV can be derived either from the ECG (using electrodes placed on the chest) or from pulse wave recordings (using a plethysmographic optical sensor placed at the fingertip or earlobe).
Changes in the autonomic nervous system are particularly sensitive to emo- tional states, and positive and negative emotions can be readily distinguished by changes in heart rhythm patterns. For example, during negative emotions such as anger, frustration, and anxiety, heart rhythm patterns become more erratic or disordered, indicating less synchronization in the reciprocal action that ensues between the parasympathetic and sympathetic branches of the ANS. In contrast, positive emotions, such as appreciation, love, and compassion, are associated with a highly ordered sine wave heart rhythm pattern, reflecting greater ANS synchronization.
Heart rhythm pattern analysis, which examines the varying shape of the HRV waveform, is a promising tool in psychophysiological research and biofeed- back application. It is particularly valuable in applications that aim to illuminate the physiological correlates of different mental and emotional states; assess the extensive interactions among the mental, emotional, and physiological systems in arousal-induced pathology; and examine psychophysiological responses to dif- ferent interventions.
Research has shown that sustained positive emotions lead to a highly efficient and regenerative functional mode associated with increased coherence or reson- ance in heart rhythm patterns and greater synchronization and harmony among physiological systems. A new development in biofeedback technology is the recent introduction of heart rhythm feedback trainers which monitor heart rhythm patterns and help people develop skills to maintain states of increased physiological coherence. The use of pulse wave sensors makes this technology extremely versatile, time-efficient, and easy to use in a wide variety of settings.
104 Biofeedback
Heart rhythm feedback trainers, like the emWave® and emWave PC developed by the Institute of HeartMath, are currently utilized in medical, mental health, corporate, academic and other settings to improve clinical, psychological, and performance outcomes. This technology holds promise as an effective, practical tool for the enhancement of health and human potential.
Heart rhythm feedback training is a powerful tool to help people learn to self- generate states of increased physiological coherence at will, thereby reducing stress and improving health, emotional well-being, and performance. Heart rhythm feed- back training also helps individuals develop emotional self-regulation skills that increase their capacity to sustain coherent states and their associated benefits.
Many health professionals have found heart rhythm monitoring and feedback to be an effective tool to support and facilitate a wide variety of therapies, both conventional and complementary. For example, this technology is increasingly being used by neurofeedback practitioners to calm clients and stabilize the nervous system before sessions that use EEG feedback protocols. This preparation often allows for a shorter and more effective session.
Many clinicians have found heart rhythm feedback to be an effective addition to treatment programs for chronic conditions that are associated with or exacer- bated by emotional stress, including fibromyalgia, chronic fatigue, hypertension, asthma, environmental sensitivity, sleep disorders, diabetes, and cardiac arrhyth- mias, among many others. Practitioners also use heart rhythm feedback devices to monitor the real-time psychophysiological effects of various therapeutic inter- ventions that affect autonomic nervous system dynamics.
In the future, it is likely that heart rhythm feedback training will be increas- ingly incorporated into programs for the prevention and treatment of cardiovas- cular diseases and arousal-induced pathologies. Its use is also likely to increase in education, as more schools incorporate programs that seek to educate students in emotional awareness and emotion regulation skills. Future developments in research, heart rhythm monitoring technologies, and pattern analysis methods will enable an even more refined electrophysiological discrimination of emotions than is currently possible. This may help therapists guide clients in developing greater awareness and understanding of their emotional responses, both conscious and subconscious, and ultimately achieving greater control over their emotional well- being and health.
One of the primary benefits of biofeedback is that it is self-empowering. As indi- viduals learn to become more sensitive to their hearts, minds, and bodies; as they become more attuned to their physiological and emotional rhythms, signals and patterns; and as they learn new self-regulating skills for stimulating, modulating and controlling various functions that affect physical and emotional health, they will experience increasing mastery of their lives. In a way, biofeedback is a way of helping the human system function as it was designed to function.
SEE ALSO: Complementary and alternative medicine Heart-brain connection Neurofeedback