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Biofeedback

Biofeedback

Definition

Biofeedback is a technique that uses monitoring instruments to measure and feed back information about muscle tension, heart rate, sweat responses, skin temperature, or brain activity.

Terms associated with biofeedback include applied psychophysiology or behavioral physiology. It is also viewed as a mind-body therapy method used in complementary and alternative medicine. Biofeedback is an important part of understanding the relationship between physical state and thoughts, feelings, and behaviors.

Purpose

The purpose of biofeedback is to enhance an individual's awareness of physical reactions to physical, emotional, or psychological stress , and their ability to influence their own physiological responses. The overall purpose is to develop self-regulation skills that play a role in improving health and well-being.

Biofeedback has been used as a part of a comprehensive treatment approach with a number of conditions, including chronic pain, irritable bowel syndrome (IBS), temporomandibular joint disorder (TMJ), Raynaud's syndrome, epilepsy, attention-deficit/hyper activity disorder (ADHD), anxiety, migraine headaches, depression, traumatic brain injury, and sleep disorders . There is some support for using biofeedback in the treatment of diabetes when self-monitoring of blood glucose levels is maintained and within the context of regular physician consultation and supervision.

Biofeedback has been a useful tool in helping individuals with urinary incontinence regain bladder control by controlling the muscles used in urination. Sensors are placed in the vaginal or anal canal to help individuals learn when the muscles are properly contracted. A recent study found that this type of biofeedback treatment was safe, effective, and well liked by women patients 55 years and older.

Conditions related to stress are also treated using biofeedback, such as certain types of headaches, high blood pressure, bruxism or teeth grinding, post-traumatic stress disorder (PTSD), eating disorders, substance abuse, and some anxiety disorders. In treatment of stress-related conditions, biofeedback is often used in combination with relaxation training. Sometimes, biofeedback is used to help individuals learn how to experience deeper relaxation, such as in childbirth education programs or general stress management. This is referred to as biofeedback-assisted relaxation training. Even for individuals who can achieve relaxation through other strategies such as meditation or relaxation, biofeedback can be a valuable added technique. Biofeedback offers special advantages, such as allowing the clinician to track closely the places where an individual tenses up and helps the individual learn what thoughts and feelings are associated with the tension.

Precautions

Biofeedback depends on the motivation and active participation of an individual. Thus, it may not be suitable for individuals with low motivation who are not willing to take a highly active role in treatment, such as those suffering from depression. Also, since biofeedback focuses on initiating behavioral changes, individuals inclined to examine their past to alleviate problems and symptoms may benefit more from other treatment types, such as psychotherapy . Individuals with cognitive impairment may be unable to remain engaged in the treatment, depending on their level of functioning. Also, individuals with a pacemaker or other implanted electrical devices should inform their health care professional before entering biofeedback training, as certain types of biofeedback sensors may interfere with the devices. Patients with specific pain symptoms in which the cause is unknown should have a thorough medical examination to rule out any serious underlying disease before starting biofeedback training. Biofeedback can be used in combination with conventional therapies; however, while it can be used in combination with conventional medical treatment for illnesses such as cancer and diabetes, it should not replace those treatments.

Research on the success of biofeedback in treating certain conditions is inconclusive or needs to be validated. Some research studies use a small number of participants, which makes it difficult to generalize the results to a larger population. Also, many conditions have different subtypes with a variety of psychological, social, and physical causes. This fact, combined with research design concerns, makes it difficult to compare research studies. For example, while most studies have reported positive outcomes in the treatment of alcohol abuse and dependence, problems with methods and statistical analyses have called study results into question. Also, its effectiveness in treating opiate abuse or dependence has not been consistently shown, as with its use in treating menopausal hot flashes, and there are limitations in studies relating to its use in cancer treatment. Continued research is needed to further evaluate and improve different biofeedback techniques for various conditions.

Description

According to the Association for Applied Psychophysiology and Biofeedback, the technique was developed in the early 1970s by psychologists and physicians. These techniques continue to be used by psychologists, physicians, nurses, and other health care professionals such as physical therapists. Prior to beginning any biofeedback training, individuals may need a comprehensive psychological, educational, and/or medical assessment. Biofeedback can be used in conjunction with nonmedical treatments, such as psychotherapy, cognitive-behavioral therapy , and behavioral treatment strategies.

How biofeedback works

Biofeedback utilizes electronic sensors, or electrodes, attached to various parts of the body to detect changes in physical responses. Signals then inform the individual of these changes by means of visual or auditory signals such as a light display or a series of beeps. While the individual views or listens to feedback, he or she begins to recognize thoughts, feelings, and mental images that influence his or her physical reactions. By monitoring this mind-body connection, the individual can use the same thoughts, feelings, and mental images as cues or reminders to become more relaxed, or to change heartbeat, brain wave patterns, body temperature, and other body functions. The individual uses trial-and-error to change the signals change in the desired direction. For example, individuals trying to control their blood pressure levels may see a light flash whenever the pressure drops below a certain level. They may then try to remember what their thoughts and feelings were at the moment and deliberately maintain them to keep the blood pressure level low.

Through training, the individual learns to control the targeted physical response and, over time, is able to recognize what is required to reduce problematic symptoms. Eventually, the external biofeedback becomes unnecessary as the individual learns to perceive internal physical responses and make the desired changes. The individual then has a powerful, portable, and self-administered treatment tool to deal with problematic symptoms.

Three stages of biofeedback training

  • Awareness of the problematic physical response: Individuals may complete a psychophysiological stress profile (PSP) to identify how their bodies respond to a variety of stressors and determine their ability to overcome undesired physical reactions. This involves a period of rest, stress, and recovery. For example, various sensors are attached to various parts of the body, and a baseline measurement lasting from two to four minutes records physical responses. The individual then goes through a standard set of stressors (such as rapid math calculations or running in place) each lasting from two to four minutes. This is followed by another relaxation period to determine the length of the recovery period.
  • Using signals from the biofeedback equipment to control physical responses: The individual is assisted in reaching certain goals related to managing a specific physical response.
  • Transferring control from biofeedback equipment or the health care professional: Individuals learn to identify triggers that alert them to implement their new-found self-regulation skills.

Types of biofeedback equipment

  • Electromyograph (EMG): Sensors (or electrodes) placed on the skin on pertinent parts of the body monitor electrical activity in muscles, specifically tension. This is the most frequently used biofeedback method in the treatment of various neurologic disorders such as stroke , cerebral palsy, traumatic brain injury, and multiple sclerosis. In children and adolescents, EMG may be used to treat tension headaches, enuresis , and encopresis . In treating TMJ or bruxism, EMG sensors are placed on jaw muscles. Chronic pain is treated by monitoring muscle tension in various places on the body.
  • Galvanic skin response (GSR): Sensors on the fingers monitor perspiration or sweating. This is also referred to as obtaining a skin conductance level (SCL). GSR may be used in the treatment of anxiety, fears or phobias, stress, and sleep problems.
  • Temperature or thermal sensors: Sensors monitor body temperature and changes in blood flow. Changes in hand temperature, for example, can indicate relaxation when there is increased blood flow to the skin. Temperature biofeedback may be useful for treating migraine headache, Raynaud's disorder, and anxiety disorders.
  • Heart rate sensors: A pulse monitor placed on the fingertip monitors pulse rate. Increases in heart rate are associated with emotional arousal, such as being angry or fearful. Decreases in heart rate are associated with relaxation.
  • Capnometry (CAP): Respiratory sensors monitor oxygen intake and carbon dioxide output. This differentiates correct breathing from problematic breathing practices. Breath control training may be used to treat panic attacks, asthma, and a variety of stress-related conditions.
  • Electroencephalographs (EEG) or neurofeedback: Sensors attached to the scalp monitor brain wave activity in different parts of the brain. It may be used to treat conditions with proven or suspected impact on brain wave patterns such as seizure disorders or epilepsy, ADHD, learning disabilities, migraine headaches, traumatic brain injury, and sleep disorders.

Biofeedback is geared toward whatever a person finds most appealing and understandable and provided in several formats such as auditory, visual, or multimedia. Audio feedback, that may take the form of changes in tone and pitch, is useful because visual attention is not necessary. Visual feedback can be provided in various forms such as bar or line graphs on a computer screen. Initially, it was thought thatover timecomputer signals could become boring or visually unappealing. In response to this, Barry Bittman developed Mindscope in 1992 that displays video scenes with realistic sounds on a high-definition television set connected to a computer. Physical responses detected by the biofeedback equipment control an engaging audiovisual environment of beautiful and realistic scenes. Clarity, perspective, motion, and sounds improve as the individual deepens their relaxation. For children and adolescents, this may be described as a "video game for the body." Visual displays for EMG biofeedback may include sports such as basketball, baseball, and golf, where the individual plays against the computer.

The setting in which biofeedback training takes place can vary. Sometimes the clinician, client, and equipment are in the same room. Sometimes the client may sit in comfortable seating in a semi-dark, quiet room while the clinician is in another room with the equipment. In this arrangement, the clinician and client may communicate using an intercom.

In some cases, children and adolescents may reach the desired level of control in three to five sessions. Depending on the condition, biofeedback training may require a series of sessions for several days or weeks. In general, it may take 10 or 15 sessions at the lower end to 40 or 50 sessions at the higher end.

Preparation

Biofeedback is most successful when individuals are motivated to learn. It is useful for people who have difficulty relaxing, even when they make efforts to do so. A receptive and open attitude is important for attaining desired responses rather than actively focusing on attaining them. It is important that individuals are willing to practice regularly at home to apply the skill to everyday life. Establishing a foundation of trust and confidence in the health care professional is an important component of biofeedback training.

Before beginning biofeedback training, an initial consultation will be conducted to record medical history, treatment background, and biofeedback goals. The procedure will be explained to provide a clear understanding of how and why the training will be helpful. The individual may be shown the equipment and told where they will be placed and how they work.

Before electrodes are placed on the body, the skin surface must be adequately prepared by using alcohol preparation pads to remove oils, makeup, and dead skin cells that may interfere with the biofeedback signal. An electrode paste is then applied to the sensor, or a small adhesive pad is used to adhere the sensor to the skin. Heart rate, temperature, and GSR monitors may be placed on the fingertip with a Velcro or elastic band. With CAP, the tip of a small, flexible, plastic tube is positioned in the nostril using tape. An individual may be taught several forms of biofeedback initially, then the training may be tailored to the individual's preference.

The biofeedback trainer must have technical skill, an understanding of basic anatomy and physiology, knowledge of various conditions, and familiarity with computer hardware and software. The American Psychological Association views biofeedback as a proficiency area, master's and doctoral level training programs are available through a variety of sources, and certification is available through the Biofeedback Certification Institute of America.

Aftercare

One or two follow-up sessions may be arranged two to four months after the initial set of appointments. In this way, long-term progress can be assessed, support can be provided, and adjustments can be made, if needed.

Risks

There are no known side effects with properly administered biofeedback. Problems may occur if biofeedback is used to treat certain conditions where the use of biofeedback is not advised.

Normal results

A normal result may be indicated by achieving the desired changes in muscle tension, heart rate, sweat activity, respiration rate, temperate change, and brainwave activity. Health care professionals may use various criteria or normal values that have been developed for some biofeedback equipment. These values indicate levels that can be expected from normal physiological functioning or relaxation. Importantly, an individual learns to control their physical reactions, which may lead to feelings of empowerment and confidence.

Abnormal results

Unusual results may arise from a number of factors, including poor sensor or electrode contact with the skin and interference from other electrical signals or "noise." Some equipment may react to room temperature conditions, especially when the room is very hot or very cold. Although inexpensive monitoring equipment is available, such as watches that monitor heartbeat and hand-held GSR devices, their results may not be accurate.

See also Anxiety and anxiety disorders; Substance abuse and related disorders

Resources

BOOKS

Culbert, Timothy P. "Biofeedback with Children and Adolescents." In Innovative Psychotherapy Techniques in Child and Adolescent Therapy., edited by C. Schaefer. 2nd ed. New York: John Wiley and Sons, 1999.

Di Franco, Joyce T. "Biofeedback." In Childbirth Education: Practice, Research and Theory, edited by F. H. Nichols and S. S. Humenick. 2nd ed. Philadelphia: W. B. Saunders, 2000.

Schwartz, Mark S. and Associates. Biofeedback: A Practitioner's Guide. New York: Guilford, 1987.

Spencer, John W. and J. J. Jacobs. Complementary/Alternative Medicine: An Evidence-Based Approach. Baltimore: Mosby, 1999.

Stoyva, Johann M. and Thomas H. Budzynski. "Biofeedback Methods in the Treatment of Anxiety and Stress Disorders." In Principles and Practice of Stress Management. edited by P. M. Lehrer and R. L. Woolfolk. 2nd ed. New York: Guilford Press, 1993.

PERIODICALS

American Psychological Association. "HCFA will cover biofeedback for incontinence." Monitor on Psychology 31, no.11 (December 2000).

Burgio, Kathryn L., Julie L. Locher, Patricia S. Goode, M. Hardin, B. Joan McDowell, and Dorothy C. Dombrowski. "Behavioral vs. Drug Treatment for Urge Urinary Incontinence in Older Women: A Randomized Controlled Trial." JAMA, The Journal of the American Medical Association 280, no. 23 (December 1998): 1995-2000.

ORGANIZATIONS

Association for Applied Psychotherapy and Biofeedback. 10200 W. 44th Avenue, Suite 304, Wheat Ridge, CO 80033-2840. (303) 422-8436. <http://www.aapb.org>.

Biofeedback Certification Institute of America. 1022 W. 44th Avenue, Suite 310, Wheat Ridge, CO 80033. (303) 420-2902. <http://www.bcia.org>.

Joneis Thomas, Ph.D.

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Biofeedback

Biofeedback

Definition

Biofeedback, or applied psychophysiological feedback, is a patient-guided treatment that teaches an individual to control muscle tension, pain , body temperature, brain waves, and other bodily functions and processes through relaxation , visualization, and other cognitive control techniques. The name biofeedback refers to the biological signals that are fed back, or returned, to the patient in order for the patient to develop techniques of manipulating them.

Origins

In 1961, Neal Miller, an experimental psychologist, suggested that autonomic nervous system responses (for instance, heart rate, blood pressure, gastrointestinal activity, regional blood flow) could be under voluntary control. As a result of his experiments, he showed that such autonomic processes were controllable. This work led to the creation of biofeedback therapy. Willer's work was expanded by other researchers. Thereafter, research performed in the 1970s by UCLA researcher Dr. Barry Sterman established that both cats and monkeys could be trained to control their brain wave patterns. Sterman then used his research techniques on human patients with epilepsy , where he was able to reduce seizures by 60% with the use of biofeedback techniques. Throughout the 1970s, other researchers published reports of their use of biofeedback in the treatment of cardiac arrhythmias, headaches, Raynaud's syndrome , and excess stomach acid, and as a tool for teaching deep relaxation. Since the early work of Miller and Sterman, biofeedback has developed into a front-line behavioral treatment for an even wider range of disorders and symptoms.

Benefits

Biofeedback has been used to successfully treat a number of disorders and their symptoms, including tempromandibular joint disorder (TMJ), chronic pain, irritable bowel syndrome (IBS), Raynaud's syndrome, epilepsy, attention-deficit hyperactivity disorder

(ADHD), migraine headaches, anxiety, depression , traumatic brain injury, and sleep disorders .

Illnesses that may be triggered at least in part by stress are also targeted by biofeedback therapy. Certain types of headaches, high blood pressure, bruxism (teeth grinding), post-traumatic stress disorder , eating disorders, substance abuse, and some anxiety disorders may be treated successfully by teaching patients the ability to relax and release both muscle and mental tension. Biofeedback is often just one part of a comprehensive treatment program for some of these disorders.

NASA has used biofeedback techniques to treat astronauts who suffer from severe space sickness, during which the autonomic nervous system is disrupted. Scientists at the University of Tennessee have adapted these techniques to treat individuals suffering from severe nausea and vomiting that is also rooted in autonomic nervous system dysfunction.

Recent research also indicates that biofeedback may be a useful tool in helping patients with urinary incontinence regain bladder control. Individuals learning pelvicfloor muscle strengthening exercises can gain better control over these muscles by using biofeedback. Sensors are placed on the muscles to train the patient where they are and when proper contractions are taking place.

Description

During biofeedback, special sensors are placed on the body. These sensors measure the bodily function that is causing the patient problem symptoms, such as heart rate, blood pressure, muscle tension (EMG or electromyographic feedback), brain waves (EEC or electroencophalographic feedback), respiration, and body temperature (thermal feedback), and translates the information into a visual and/or audible readout, such as a paper tracing, a light display, or a series of beeps.

While the patient views the instantaneous feedback from the biofeedback monitors, he or she begins to recognize what thoughts, fears, and mental images influence his or her physical reactions. By monitoring this relationship between mind and body, the patient can then use these same thoughts and mental images as subtle cues, as these act as reminders to become deeply relaxed, instead of anxious. These reminders also work to manipulate heart beat, brain wave patterns, body temperature, and other bodily functions. This is achieved through relaxation exercises, mental imagery, and other cognitive therapy techniques.

As the biofeedback response takes place, patients can actually see or hear the results of their efforts instantly through the sensor readout on the biofeedback equipment. Once these techniques are learned and the patient is able to recognize the state of relaxation or visualization necessary to alleviate symptoms, the biofeedback equipment itself is no longer needed. The patient then has a powerful, portable, and self-administered treatment tool to deal with problem symptoms.

Biofeedback that specializes in reading and altering brain waves is sometimes called neurofeedback. The brain produces four distinct types of brain wavesdelta, theta, alpha, and betathat all operate at a different frequency. Delta, the slowest frequency wave, is the brain wave pattern associated with sleep. Beta waves, which occur in a normal, waking state, can range from 12-35 Hz. Problems begin to develop when beta wave averages fall in the low end (underarousal) or the high end (over-arousal) of that spectrum. Underarousal might be present in conditions such as depression or attention-deficit disorder, and overarousal may be indicative of an anxiety disorder, obsessive compulsive disorder, or excessive stress. Beta wave neurofeedback focuses on normalizing that beta wave pattern to an optimum value of around 14 Hz. A second type of neurofeedback, alpha-theta, focuses on developing the more relaxing alpha (8-13 Hz) and theta waves (4-9 Hz) that are usually associated with deep, meditative states, and has been used with some success in substance abuse treatment.

Through brain wave manipulation, neurofeedback can be useful in treating a variety of disorders that are suspected or proven to impact brain wave patterns, such as epilepsy, attention-deficit disorder, migraine headaches, anxiety, depression, traumatic brain injury, and sleep disorders. The equipment used for neurofeedback usually uses a monitor as an output device. The monitor displays specific patterns that the patient attempts to change by producing the appropriate type of brain wave. Or, the monitor may reward the patient for producing the appropriate brain wave by producing a positive reinforcer, or reward. For example, children may be rewarded with a series of successful moves in a displayed video game.

Depending on the type of biofeedback, individuals may need up to 30 sessions with a trained professional to learn the techniques required to control their symptoms on a long-term basis. Therapists usually recommend that their patients practice both biofeedback and relaxation techniques on their own at home.

Preparations

Before initiating biofeedback treatment, the therapist and patient will have an initial consultation to record the patients medical history and treatment background and discuss goals for therapy.

Before a neurofeedback session, an EEG is taken from the patient to determine his or her baseline brainwave pattern.

ELMER GREEN 1917


A life dedicated to science has propelled Elmer Green, Ph.D. into careers as a physicist and a biological psychologist. Both led to his most noted work, the influence on the birth of the biofeedback movement. While the mechanics of moving parts and machinery lured the investigator from LaGrand, Oregon, to his work as a civilian scientist with the Navy in the late 1940s, it was his wife Alyce who caused him to ponder biophysiology and human development. In 1953 she read a book titled The Human Senses by Frank Geldard. It was their interests as a couple that led to their continued education at the University of Chicago. In 1957 Green began work for his Ph.D. studies in biopsychology, while Alyce studied for her Master's degree in psychology.

Numerous opportunities, including assisting with the development of a machine for the automated detection of brain damage, led to his position at the Menninger Institute in Topeka, Kansas, in 1964. While there he established the psychophysiology laboratory and the Voluntary Controls Program. It was his treatment of a colleague's wife's headaches that Green became convinced that skin temperature was an autonomic nervous system variable that was responsive to psychophysiologic self-regulation aided by thermal biofeedback. By learning to control temperature he found that headache control could be enhanced. Green's success attracted support by several of the Menninger staff who also began research and use of biofeedback therapy for headaches and hypertension.

The 1960s proved exciting for Green as he, Alyce, and colleague Dale Walters became involved with EEG Biofeedback, and studied the process of meditationa therapy the Greens had long practiced. In April 1969, Green and his wife organized the Council Grove Conference for the study of the voluntary control of internal states. The conference served as a step toward forming the Biofeedback Research Society, which later became the Biofeedback Society of America, and currently the Association for Applied Psychophysiology and Biofeedback.

Together, Elmer and Alyce Green authored numerous papers, book chapters, and wrote the book, Beyond Biofeedback (1977). They lectured throughout the United States and around the world for more than 20 years on multiple topics including EEG biofeedback training and psychophysiologic control.

Green co-founded the International Society For the Study of Subtle Energies and Energy Medicine (ISSSEEM) in 1990 and served as its director. Alyce died in 1994 of Alzheimer's disease. In 2000, 81-year-old Green worked as a professional consultant and director emeritus of the Voluntary Controls Program at the Menninger Clinic. He also served as the science director of the Dove Health Alliance in Aptos, California.

Beth A. Kapes

Biofeedback typically is performed in a quiet and relaxed atmosphere with comfortable seating for the patient. Depending on the type and goals of biofeedback being performed, one or more sensors will be attached to the patient's body with conductive gel and/or adhesives. These may include:

  • Electromyographic (EMG) sensors. EMG sensors measure electrical activity in the muscles, specifically muscle tension. In treating TMJ or bruxism, these sensors would be placed along the muscles of the jaw. Chronic pain might be treated by monitoring electrical energy in other muscle groups.
  • Galvanic skin response (GSR) sensors. These are electrodes placed on the fingers that monitor perspiration, or sweat gland, activity. These may also be called skin conductance level (SCL).
  • Temperature sensors. Temperature, or thermal, sensors measure body temperature and changes in blood flow.
  • Electroencephalography (EEG) sensors. These electrodes are applied to the scalp to measure the electrical activity of the brain, or brain waves.
  • Heart rate sensors. A pulse monitor placed on the finger tip can monitor pulse rate.
  • Respiratory sensors. Respiratory sensors monitor oxygen intake and carbon dioxide output.

Precautions

Individuals who use a pacemaker or other implantable electrical devices should inform their biofeedback therapist before starting treatments, as certain types of biofeedback sensors have the potential to interfere with these devices.

Biofeedback may not be suitable for some patients. Patients must be willing to take a very active role in the treatment process. And because biofeedback focuses strictly on behavioral change, those patients who wish to gain insight into their symptoms by examining their past might be better served by psychodynamic therapy.

Biofeedback may also be inappropriate for cognitively impaired individuals, such as those patients with organic brain disease or a traumatic brain injury, depending on their levels of functioning.

Patients with specific pain symptoms of unknown origin should undergo a thorough medical examination before starting biofeedback treatments to rule out any serious underlying disease. Once a diagnosis has been made, biofeedback can be used concurrently with conventional treatment.

Biofeedback may only be one component of a comprehensive treatment plan. For illnesses and symptoms that are manifested from an organic disease process, such as cancer or diabetes, biofeedback should be an adjunct to (complementary to), and not a replacement for, conventional medical treatment.

Side effects

There are no known side effects to properly administered biofeedback or neurofeedback sessions.

Research & general acceptance

Preliminary research published in late 1999 indicated that neurofeedback may be a promising new tool in the treatment of schizophrenia . Researchers reported that schizophrenic patients had used neurofeedback to simulate brain wave patterns that antipsychotic medications produce in the brain. Further research is needed to determine what impact this may have on treatment for schizophrenia.

KEY TERMS

Raynaud's syndrome
A vascular, or circulatory system, disorder which is characterized by abnormally cold hands and feet. This chilling effect is caused by constriction of the blood vessels in the extremities, and occurs when the hands and feet are exposed to cold weather. Emotional stress can also trigger the cold symptoms.

The use of biofeedback techniques to treat an array of disorders has been extensively described in the medical literature. Controlled studies for some applications are limited, such as for the treatment of menopausal symptoms and premenstrual disorder (PMS). There is also some debate over the effectiveness of biofeedback in ADHD treatment, and the lack of controlled studies on that application. While many therapists, counselors, and mental health professionals have reported great success with treating their ADHD patients with neurofeedback techniques, some critics attribute this positive therapeutic impact to a placebo effect .

There may also be some debate among mental health professionals as to whether biofeedback should be considered a first line treatment for some mental illnesses, and to what degree other treatments, such as medication, should be employed as an adjunct therapy.

Training & certification

Individuals wishing to try biofeedback should contact a healthcare professional trained in biofeedback techniques. Licensed psychologists, psychiatrists, and physicians frequently train their patients in biofeedback techniques, or can recommend a specialist who does. In some cases, a licensed professional may employ a biofeedback technician who works under their direct guidance when treating patients. There are several national organizations for biofeedback therapists, including the Biofeedback Certification Institute of America, which also certifies therapists in the practice.

Resources

BOOKS

Robbins, Jim. A Symphony in the Brain: The Evolution of the New Brain Wave Biofeedback. Boston, MA: Atlantic Monthly Press, 2000.

PERIODICALS

Burgio, K.L. et al. "Behavioral vs. Drug Treatment for Urge Urinary Incontinence in Older Women: A randomized controlled trial." Journal of the American Medical Association 280 (Dec. 1998): 1995-2000.

Robbins, Jim. "On the Track with Neurofeedback." Newsweek 135, no. 25 (June 2000): 76.

ORGANIZATIONS

The Association for Applied Psychotherapy and Biofeedback. 10200 W. 44th Avenue, Suite 304, Wheat Ridge, CO 80033-2840. (303) 422-8436. <http://www.aapb.org>.

Biofeedback Certification Institute of America. 10200 W. 44th Avenue, Suite 310, Wheat Ridge, CO 80033. (303) 420-2902.

Paula Ford-Martin

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Ford-Martin, Paula. "Biofeedback." Gale Encyclopedia of Alternative Medicine. 2005. Encyclopedia.com. (September 25, 2016). http://www.encyclopedia.com/doc/1G2-3435100091.html

Ford-Martin, Paula. "Biofeedback." Gale Encyclopedia of Alternative Medicine. 2005. Retrieved September 25, 2016 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-3435100091.html

Biofeedback

Biofeedback

Definition

Biofeedback, or applied psychophysiological feedback, is a patient-guided treatment that teaches an individual to control muscle tension, pain, body temperature, brain waves, and other bodily functions and processes through relaxation, visualization, and other cognitive control techniques. The name biofeedback refers to the biological signals that are fed back, or returned, to the patient in order for the patient to develop techniques of manipulating them.

Purpose

Biofeedback has been used to successfully treat a number of disorders and their symptoms, including temporomandibular joint disorder (TMJ), chronic pain, irritable bowel syndrome (IBS), Raynaud's syndrome, epilepsy, attention-deficit hyperactivity disorder (ADHD ), migraine headaches, anxiety, depression, traumatic brain injury, and sleep disorders.

Illnesses that may be triggered at least in part by stress are also targeted by biofeedback therapy. Certain types of headaches, high blood pressure, bruxism (teeth grinding), post-traumatic stress disorder, eating disorders, substance abuse, and some anxiety disorders may be treated successfully by teaching patients the ability to relax and release both muscle and mental tension. Biofeedback is often just one part of a comprehensive treatment program for some of these disorders.

NASA has used biofeedback techniques to treat astronauts who suffer from severe space sickness, during which the autonomic nervous system is disrupted. Scientists at the University of Tennessee have adapted these techniques to treat individuals suffering from severe nausea and vomiting that is also rooted in autonomic nervous system dysfunction.

Recent research also indicates that biofeedback may be a useful tool in helping patients with urinary incontinence regain bladder control. Individuals learning pelvic-floor muscle strengthening exercises can gain better control over these muscles by using biofeedback. Sensors are placed on the muscles to train the patient where they are and when proper contractions are taking place.

Description

Origins

In 1961, Neal Miller, an experimental psychologist, suggested that autonomic nervous system responses (for instance, heart rate, blood pressure, gastrointestinal activity, regional blood flow) could be under voluntary control. As a result of his experiments, he showed that such autonomic processes were controllable. This work led to the creation of biofeedback therapy. Willer's work was expanded by other researchers. Thereafter, research performed in the 1970s by UCLA researcher Dr. Barry Sterman established that both cats and monkeys could be trained to control their brain wave patterns. Sterman then used his research techniques on human patients with epilepsy, where he was able to reduce seizures by 60% with the use of biofeedback techniques. Throughout the 1970s, other researchers published reports of their use of biofeedback in the treatment of cardiac arrhythmias, headaches, Raynaud's syndrome, and excess stomach acid, and as a tool for teaching deep relaxation. Since the early work of Miller and Sterman, biofeedback has developed into a front-line behavioral treatment for an even wider range of disorders and symptoms.

During biofeedback, special sensors are placed on the body. These sensors measure the bodily function that is causing the patient problem symptoms, such as heart rate, blood pressure, muscle tension (EMG or electromyographic feedback), brain waves (EEC or electroencophalographic feedback), respiration, and body temperature (thermal feedback), and translates the information into a visual and/or audible readout, such as a paper tracing, a light display, or a series of beeps.

While the patient views the instantaneous feedback from the biofeedback monitors, he or she begins to recognize what thoughts, fears, and mental images influence his or her physical reactions. By monitoring this relationship between mind and body, the patient can then use these same thoughts and mental images as subtle cues, as these act as reminders to become deeply relaxed, instead of anxious. These reminders also work to manipulate heart beat, brain wave patterns, body temperature, and other bodily functions. This is achieved through relaxation exercises, mental imagery, and other cognitive therapy techniques.

KEY TERMS

Autonomic nervous system The part of the nervous system that controls so-called involuntary functions, such as heart rate, salivary gland secretion, respiratory function, and pupil dilation.

Bruxism Habitual, often unconscious, grinding of the teeth.

Epilepsy A neurological disorder characterized by the sudden onset of seizures.

Placebo effect Placebo effect occurs when a treatment or medication with no known therapeutic value (a placebo) is administered to a patient, and the patient's symptoms improve. The patient believes and expects that the treatment is going to work, so it does. The placebo effect is also a factor to some degree in clinically-effective therapies, and explains why patients respond better than others to treatment despite similar symptoms and illnesses.

Raynaud's syndrome A vascular, or circulatory system, disorder which is characterized by abnormally cold hands and feet. This chilling effect is caused by constriction of the blood vessels in the extremities, and occurs when the hands and feet are exposed to cold weather. Emotional stress can also trigger the cold symptoms.

Schizophrenia Schizophrenia is a psychotic disorder that causes distortions in perception (delusions and hallucinations), inappropriate moods and behaviors, and disorganized or incoherent speech and behavior.

Temporomandibular joint disorder Inflammation, irritation, and pain of the jaw caused by improper opening and closing of the temporomandibular joint. Other symptoms include clicking of the jaw and a limited range of motion.

As the biofeedback response takes place, patients can actually see or hear the results of their efforts instantly through the sensor readout on the biofeedback equipment. Once these techniques are learned and the patient is able to recognize the state of relaxation or visualization necessary to alleviate symptoms, the biofeedback equipment itself is no longer needed. The patient then has a powerful, portable, and self-administered treatment tool to deal with problem symptoms.

Biofeedback that specializes in reading and altering brain waves is sometimes called neurofeedback. The brain produces four distinct types of brain wavesdelta, theta, alpha, and betathat all operate at a different frequency. Delta, the slowest frequency wave, is the brain wave pattern associated with sleep. Beta waves, which occur in a normal, waking state, can range from 12-35 Hz. Problems begin to develop when beta wave averages fall in the low end (underarousal) or the high end (overarousal) of that spectrum. Underarousal might be present in conditions such as depression or attention-deficit disorder, and overarousal may be indicative of an anxiety disorder, obsessive compulsive disorder, or excessive stress. Beta wave neurofeedback focuses on normalizing that beta wave pattern to an optimum value of around 14 Hz. A second type of neurofeedback, alpha-theta, focuses on developing the more relaxing alpha (8-13 Hz) and theta waves (4-9 Hz) that are usually associated with deep, meditative states, and has been used with some success in substance abuse treatment.

Through brain wave manipulation, neurofeedback can be useful in treating a variety of disorders that are suspected or proven to impact brain wave patterns, such as epilepsy, attention-deficit disorder, migraine headaches, anxiety, depression, traumatic brain injury, and sleep disorders. The equipment used for neurofeedback usually uses a monitor as an output device. The monitor displays specific patterns that the patient attempts to change by producing the appropriate type of brain wave. Or, the monitor may reward the patient for producing the appropriate brain wave by producing a positive reinforcer, or reward. For example, children may be rewarded with a series of successful moves in a displayed video game.

Depending on the type of biofeedback, individuals may need up to 30 sessions with a trained professional to learn the techniques required to control their symptoms on a long-term basis. Therapists usually recommend that their patients practice both biofeedback and relaxation techniques on their own at home.

Preparations

Before initiating biofeedback treatment, the therapist and patient will have an initial consultation to record the patients medical history and treatment background and discuss goals for therapy.

Before a neurofeedback session, an EEG is taken from the patient to determine his or her baseline brainwave pattern.

Biofeedback typically is performed in a quiet and relaxed atmosphere with comfortable seating for the patient. Depending on the type and goals of biofeedback being performed, one or more sensors will be attached to the patient's body with conductive gel and/or adhesives. These may include:

  • Electromyographic (EMG) sensors. EMG sensors measure electrical activity in the muscles, specifically muscle tension. In treating TMJ or bruxism, these sensors would be placed along the muscles of the jaw. Chronic pain might be treated by monitoring electrical energy in other muscle groups.
  • Galvanic skin response (GSR) sensors. These are electrodes placed on the fingers that monitor perspiration, or sweat gland, activity. These may also be called skin conductance level (SCL).
  • Temperature sensors. Temperature, or thermal, sensors measure body temperature and changes in blood flow.
  • Electroencephalography (EEG) sensors. These electrodes are applied to the scalp to measure the electrical activity of the brain, or brain waves.
  • Heart rate sensors. A pulse monitor placed on the finger tip can monitor pulse rate.
  • Respiratory sensors. Respiratory sensors monitor oxygen intake and carbon dioxide output.

Precautions

Individuals who use a pacemaker or other implantable electrical devices should inform their biofeedback therapist before starting treatments, as certain types of biofeedback sensors have the potential to interfere with these devices.

Biofeedback may not be suitable for some patients. Patients must be willing to take a very active role in the treatment process. And because biofeedback focuses strictly on behavioral change, those patients who wish to gain insight into their symptoms by examining their past might be better served by psychodynamic therapy.

Biofeedback may also be inappropriate for cognitively impaired individuals, such as those patients with organic brain disease or a traumatic brain injury, depending on their levels of functioning.

Patients with specific pain symptoms of unknown origin should undergo a thorough medical examination before starting biofeedback treatments to rule out any serious underlying disease. Once a diagnosis has been made, biofeedback can be used concurrently with conventional treatment.

Biofeedback may only be one component of a comprehensive treatment plan. For illnesses and symptoms that are manifested from an organic disease process, such as cancer or diabetes, biofeedback should be an adjunct to (complementary to), and not a replacement for, conventional medical treatment.

Side effects

There are no known side effects to properly administered biofeedback or neurofeedback sessions.

Research and general acceptance

Preliminary research published in late 1999 indicated that neurofeedback may be a promising new tool in the treatment of schizophrenia. Researchers reported that schizophrenic patients had used neurofeedback to simulate brain wave patterns that antipsychotic medications produce in the brain. Further research is needed to determine what impact this may have on treatment for schizophrenia.

The use of biofeedback techniques to treat an array of disorders has been extensively described in the medical literature. Controlled studies for some applications are limited, such as for the treatment of menopausal symptoms and premenstrual disorder (PMS). There is also some debate over the effectiveness of biofeedback in ADHD treatment, and the lack of controlled studies on that application. While many therapists, counselors, and mental health professionals have reported great success with treating their ADHD patients with neurofeedback techniques, some critics attribute this positive therapeutic impact to a placebo effect.

There may also be some debate among mental health professionals as to whether biofeedback should be considered a first line treatment for some mental illnesses, and to what degree other treatments, such as medication, should be employed as an adjunct therapy.

Resources

BOOKS

Robbins, Jim. A Symphony in the Brain: The Evolution of the New Brain Wave Biofeedback. Boston, MA: Atlantic Monthly Press, 2000.

PERIODICALS

Robbins, Jim. "On the Track with Neurofeedback." Newsweek 135, no. 25 (June 2000): 76.

ORGANIZATIONS

Association for Applied Psychotherapy and Biofeedback. 10200 W. 44th Avenue, Suite 304, Wheat Ridge, CO 80033-2840. (303) 422-8436. http://www.aapb.org.

Biofeedback Certification Institute of America.10200 W. 44th Avenue, Suite 310, Wheat Ridge, CO 80033. (303) 420-2902.

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Ford-Martin, Paula. "Biofeedback." Gale Encyclopedia of Medicine, 3rd ed.. 2006. Encyclopedia.com. 25 Sep. 2016 <http://www.encyclopedia.com>.

Ford-Martin, Paula. "Biofeedback." Gale Encyclopedia of Medicine, 3rd ed.. 2006. Encyclopedia.com. (September 25, 2016). http://www.encyclopedia.com/doc/1G2-3451600241.html

Ford-Martin, Paula. "Biofeedback." Gale Encyclopedia of Medicine, 3rd ed.. 2006. Retrieved September 25, 2016 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-3451600241.html

Biofeedback

Biofeedback

A technique that allows individuals to monitor their own physiological processes so they can learn to control them.

Biofeedback originated with the field of psychophysiology, which measures physiological responses as a way of studying human behavior. Types of behavior that may be studied in this way range from basic emotional responses to higher cognitive functions. Today, biofeedback is also associated with behavioral medicine, which combines behavioral and biomedical science in both clinical and research settings. In biofeedback training, the monitoring of physiological responses is performed for therapeutic instead of (or in addition to) investigative purposes. Biofeedback has been applied with success to a variety of clinical problems, ranging from migraine headaches to hypertension.

The technique provides people with continuous information about physiological processes of which they are normally unaware, such as blood pressure or heart rate. Through special equipment, these processes are recorded, and the information is relayed back to the person through a changing tone or meter reading. With practice, people learn strategies that enable them to achieve voluntary control over the processes involved. For example, persons trying to control their blood pressure levels may see a light flash whenever the pressure drops below a certain level. They may then try to remember and analyze what their thoughts or emotions were at that moment and deliberately repeat them to keep the pressure level low. Initially, they may simply be asked to try and keep the light flashing for as long as possible and given verbal reinforcement for their efforts.

The biofeedback training may continue for several days or weeks, with the subjects trying to keep the light flashing for longer periods in subsequent sessions. Eventually they will need to produce the desired response without electronic feedback, a goal which can be accomplished through various methods. They may practice the learned response at the end of the training session or at home between sessions. There can also be random trials without feedback during the sessions. An alternate strategy is the gradual and systematic removal of the feedback signal during the training sessions over a period of time. After the initial training is completed, subjects may return to the biofeedback facility to assess their retention of the skills they have learned or for additional training.

Biofeedback training has been used in treating a number of different clinical problems. Monitoring of patients' heart rates has been used with some success to help people suffering from heartbeat irregularities, including premature ventricular contractions (PVCs) and tachycardia, while hypertensive individuals have been

able to control high blood pressure through the use of biofeedback. Clinicians have been particularly successful in their use of neuromuscular feedback to treat complaints arising from tension in specific muscles or muscle groups. Tension headaches have been alleviated through the reduction of frontalis (forehead) tension, and relaxation of the face and neck muscles has been helpful to stutterers. Feedback from muscle groups has been helpful in the rehabilitation of stroke patients and other persons with neuromuscular disorders such as foot drop. These patients may be unable to relax or contract muscles at will, and biofeedback can make them aware of small, otherwise imperceptible changes in the desired direction and allow them to repeat and eventually increase such changes.

In addition to its alleviation of physical complaints, neuromuscular biofeedback has been an effective tool in the treatment of chronic anxiety, even when it has resisted psychotherapy and medication. By learning deep muscle relaxation, anxious patients, including those suffering from related conditions such as insomnia, have seen a reduction in their symptoms. Even for patients who have been able to achieve relaxation through other means, such as meditation or progressive relaxation, biofeedback can be a valuable supplementary technique that offers special advantages, such as allowing a therapist to track closely the points at which a patient tenses up and try to learn what thoughts are associated with the tension. Biofeedback-induced relaxation of forehead muscles has also been effective in treating asthma.

Another type of biofeedback involves the monitoring of brain activity through electroencephalographs (EEGs). A reduction of seizures in epileptics has been reported through biofeedback techniques involving EEG activity near the sensorimotor cortex, known as sensory motor rhythm. Brain wave activity has also been of interest in connection with alpha waves, which are thought to characterize a desirable state of relaxed alertness. Patients have been taught to increase their alpha rhythms in three or four 30-minute conditioning sessions.

Further Reading

Andreassi, John L. Psychophysiology: Human Behavior and Physiological Response. New York: Oxford University Press, 1980.

Beatty, J., and H. Legewie, eds. Biofeedback and Behavior. New York: Plenum Press, 1977.

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Biofeedback

Biofeedback

A term covering a range of EEG (electroencephalographic) feedback instruments and techniques, as well as apparatus giving information on other biological functions. Biofeedback instruments can convey to the subject the characteristics of his own brainwaves, skin resistance, or heartbeats so that he can learn to modify these functions consciously. In this way, the subject can enhance his capacity for relaxation or reproduce some of the psycho-physiological control shown by yogis and Zen masters.

Modification of brainwaves by biofeedback machines was first introduced in the United States by Joe Kamiya in the late 1960s; Elmer Green of the Menninger Clinic promoted the practice through the 1970s. It appeared that biofeedback could become a major technique within transpersonal psychology, and that subjects could be trained to control or to generate brain wave activity at will, thus achieving altered states of consciousness leading to the production of various psychic, spiritual, and mystical experiences.

The chief brain waves identified within biofeedback studies are: alpha (related to relaxation and dream states), frequency 8 to 13 cycles per second (cps); beta (mental and visual activity), 14 to 50 cps; theta (dream and sleep states), 4 to 7 cps; and delta (deep sleep states), 0.5 to 3.5 cps.

The simple relationship first thought to exist between brain waves and psychic and spiritual development proved to be much more complicated and ambiguous than originally believed. At present biofeedback has been used mainly in teaching people to alter various body functions to improve their health; it has been particularly effective in cases of migraine headaches.

Sources:

Green, Elmer. "Biofeedback for Mind-Body Self-Regulation: Healing and Creativity." In The Varieties of Healing Experience: Exploring Psychic Phenomena and Healing. Los Altos, Calif.: Academy of Parapsychology and Medicine, 1971.

Kamiya, Joe. "Conscious Control of Brain Waves." Psychology Today 1, no. 11 (April 1968).

Stearn, Jess. The Power of Alpha-Thinking: Miracle of the Mind. New York: William Morrow, 1976. Reprint, New York: New American Library, 1977.

Timmons, Beverly, and Joe Kamiya. "The Psychology and Physiology of Meditation and Related Phenomena." Journal of Transpersonal Psychology 1 (1970).

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biofeedback

biofeedback, method for learning to increase one's ability to control biological responses, such as blood pressure, muscle tension, and heart rate. Sophisticated instruments are often used to measure physiological responses and make them apparent to the patient, who then tries to alter and ultimately control them without the aid of monitoring devices. Biofeedback programs have been used to teach patients to relax muscles or adjust blood flow in the case of headache, to help partially paralyzed stroke victims activate muscles, and to alleviate anxiety in dental patients.

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biofeedback

biofeedback In alternative medicine, the use of monitoring systems to provide information about body processes to enable them to be controlled voluntarily. By observing data on events that are normally involuntary, such as breathing and the heartbeat, many people learn to gain control over them to some extent in order to improve well-being. The technique has proved helpful in a number of conditions, including migraine and hypertension.

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biofeedback

biofeedback The technique whereby a subject can learn to control certain body functions, such as heart rate or blood pressure, that are usually unconsciously regulated by the autonomic nervous system. It is facilitated by the use of monitoring devices, such as pulse monitors, electroencephalographs, and electromyographs, and can be useful in treating high blood pressure, migraine, epilepsy, and other disorders.

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"biofeedback." A Dictionary of Biology. 2004. Encyclopedia.com. 25 Sep. 2016 <http://www.encyclopedia.com>.

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biofeedback

bi·o·feed·back / ˌbīōˈfēdˌbak/ • n. the use of electronic monitoring of a normally automatic bodily function in order to train someone to acquire voluntary control of that function.

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