Biofeedback in Medicine Biofeedback Modalities

Biofeedback is a treatment technique in which people are trained to improve their health by using signals from their own bodies. Ever since its advent, biofeedback has made rapid strides in the field of medicine. Biofeedback modalities like temperature, EMG, EDR (electrodermal response) and EEG biofeedback have been extensively tried in the management of diseases, particularly the stress-induced ones. Biofeedback is an important tool for stress management and is effective in various diseases like anxiety, hypertension, migraine, tension headache, epilepsy, chronic pain, chronic constipation, fecal incontinence, irritable bowel syndrome and bronchial asthma. Besides the conventional forms of biofeedback, the development of other modalities like Hemoencephalography (HEG) and Heart rate variation (HRV) biofeedback has extended the scope of biofeedback in medicine. Biofeedback can reduce or even eliminate the need for medication and can be useful for prophylaxis of certain diseases. Emergence of telemedicine has added new possibilities for learning biofeedback by the patient even if the service provider is at a remote place. All clinicians should be conversant with this therapeutic modality as it may be useful in conditions refractory to conventional treatment. However, inspite of extensive clinical trials, more research is required for recommendation of biofeedback in diseases where its role is not yet specifically known. What is Biofeedback? Biofeedback is a form of self-regulation in which individuals learn to control physiological responses by providing them with an information signal, as sensory feedback, about biological conditions of which they may not be ordinarily aware. Feedback responses include muscle tension, skin surface temperature, brain wave activity, electrodermal response, blood pressure and heart rate. In combination with therapeutic instruction and practice, the feedback signals enable patients to become active participants in the rehabilitation or health maintenance process.1 Biofeedback involves the application of operant conditioning to gain control of visceral, somatomotor, or central nervous system activities.2 Biofeedback emerged as a treatment method from pioneering learning research during the 1950s of experimental psychologists, such as Neal Miller. It became a clinical modality in the late 1960s.1 Biofeedback Modalities Different techniques may be used by the therapist to gather information about the body’s responses. Selection of the right technique for an individual will depend on his particular health problems and objectives. Machines and techniques include: Electromyogram (EMG) Biofeedback An EMG uses electrodes or other types of sensors to measure muscle tension. By the EMG alerting one to muscle tension, one can learn to recognize the feeling of increased muscle tension early and try to control the tension right away. EMG is mainly used to promote the relaxation of the muscles involved in backaches, headaches, neck pain and grinding the teeth (bruxism). An EMG may be used to treat some illnesses in which the symptoms tend to worsen under stress, such as asthma and ulcers. Temperature Biofeedback Skin temperature can be measured by sensors attached to fingers or feet. The temperature often drops when one is under stress, so a low reading can prompt one to begin relaxation techniques. Temperature biofeedback can help treat certain circulatory disorders, such as Raynaud’s disease,3 or reduce the frequency of migraines.4 Electrodermal Response (EDR) Biofeedback The activity of the sweat glands and the amount of perspiration on the skin can be measured by sensors, alerting one to anxiety. This information can be useful in treating emotional disorders like phobias, anxiety and stuttering. Electroencephalogram (EEG) Biofeedback The evolution of microcomputers, miniaturization, and digital technology has caused a rejuvenation in EEG feedback, re-christened “neurofeedback” or “neurofeedback therapy” (NFT). Among the areas of growing importance to clinicians include quantified (Q) EEG, the training of peak or optimal performance. ADD (Attention deficit disorder)/ADHD (Attention deficit hyperactivity disorder), treatment of dissociation, pain management in fibromyalgia and other areas of chronic pain, and enhancing mental functioning in the elderly. Modern EEG feedback equipment offers real time topographic EEG mapping in addition to additional channels that measure EMG, ECG (electrocardiogram) and EDR.1 Other Types of Biofeedback Instruments Other biofeedback machines can monitor heart rate, blood pressure and respiration all of which change in response to stress. Hemoencephalography biofeedback device monitors blood perfusion or blood oxygenation inside the brain with an infrared sensor on a headband. Practice of activating certain sites on the head, enhances a corresponding function in the brain. Comprehensive biofeedback training involves working with a therapist using any combination of several different biofeedback modalities (skin conductance, temperature, muscle tension, heart rate variability, respiration, and brain wave patterns). Typically, about six sessions of this type of training are required to learn self-regulation. How Does Biofeedback Work? As a Stress Modifier Biofeedback operates on the notion that we have the innate ability and potential to influence the autonomic functions of our bodies through the exertion of will and mind. Biofeedback shows the physiological effects of stress and our ‘behavior’ directly as they occur and in the hands of a trained clinician or therapist, can help the patient to go through a learning process. In this process the patient becomes aware of the effects of stress on the body and learns how to make the required ‘behavioral’ or ‘lifestyle’ changes. Biofeedback is often aimed at changing habitual reactions to stress that can cause pain or disease. Most patients who benefit from biofeedback are trained to relax and modify their behavior. Relaxation is a key component in biofeedback treatment of many disorders, particularly those brought on or made worse by stress. In itself, relaxation is characterized by a decreased metabolism, heart rate, blood pressure, and rate of breathing as well as an increase in skin temperature. Feedback of physical responses such as skin temperature and muscle tension provides information to help patients recognize a relaxed state. The feedback signal may also act as a kind of reward for reducing tension. Constitutive nitric oxide as a result of the relaxation approach may crucially contribute to potentially beneficial outcomes and effects in diverse pathologies, exerting a global healing effect.5