Research Findings Biofeedback: Three Decades of "Little" Breakthroughs Excerpted from the "Mind-Body Connection," The Center for Mind/Body Medicine This is the first of a series of occasional articles on research findings in an important area of mind-body medicine. Some of the most important "breakthroughs" in the field of biofeedback have come not from one definitive study but from the accumulation of numerous studies over many years. Rather than focusing only on the latest published articles, we felt it important to place the field of biofeedback in its historical context. Back in the 1960s when experimental psychologist Neal Miller first demonstrated that the autonomic nervous system could be trained to alter some bodily processes, it was thought biofeedback would change the world. Miller's discovery uprooted the prevailing paradigm, that the autonomic, or visceral, nervous system was basically "dumb" and beyond voluntary control. At the time, some scientists predicted that biofeedback eventually would allow patients to "take a fully active and direct role in literally learning not to be sick" (Dienstfrey, 1991). Over the next three decades, some 3,000 articles and 100 books on biofeedback were published. And although the research has not uncovered the kind of "unified field" originally hoped for, biofeedback has been shown to be an effective treatment for dozens of specific ailments. These include bronchial asthma, drug and alcohol abuse, anxiety, tension and migraine headaches, cardiac arrhythmias, essential hypertension, Raynaud's disease/syndrome, fecal and urinary incontinence, irritable bowel syndrome, muscle reeducation, hyperactivity and attention deficit disorder, epilepsy, menopausal hot flashes, chronic pain syndromes, and anticipatory nausea and vomiting associated with chemotherapy. While biofeedback has been used successfully to treat some psychological and mental disorders, it seems to work best with patients in which physiological processes are relevant (Futterman & Shapiro, 1986). The most common forms of biofeedback today make use of instruments to "feed back" information about such bodily processes as muscle tension (EMG feedback), skin temperature (thermal feedback), brain waves (EEG feedback) and respiration. By watching the monitoring device, patients can adjust their thinking and other mental processes in order to control bodily processes. In some cases, subjects learn by trial and error what kind of thinking or behavior affects those processes. In other cases, subjects are taught specific methods, such as relaxation or imagery, which it is believed will have an impact on bodily functions. One of the most exciting areas of biofeedback research today is the use of alpha-theta brainwave training. This therapy has proven effective in the treatment of various disorders, including chemical dependence, post-traumatic stress disorder, depression, anxiety, multiple personality, panic and eating disorders. Drs. Eugene Peniston and Paul Kulkosky's (1989, 1990, 1991) pioneering work showed that training chronic alcoholics to increase the lower-frequency alpha and theta brain waves, while controlling the higher frequency beta waves, resulted in significantly less depression, less craving for alcohol and less relapse. (The alpha brain wave has been associated with a tranquil, serene state, while the theta wave corresponds to a deeper meditative state.) The researchers' treatment protocol includes 6-8 weeks of thermal biofeedback and autogenic training, followed by 30 sessions of evoked images of personal change and alpha-theta EEG biofeedback. The sessions are performed twice a day, five days a week. The results of the therapy have been nothing short of remarkable--80 percent short-term effectiveness, with ongoing studies tracking the long-term results. The training resulted not only in decreases in alcoholic behavior (relapse, cravings, etc.) but changes in a wide range of dysfunctional personality factors (Peniston & Kulkosky, 1990). The training even affected blood chemistry: serum Beta-endorphin levels increased in patients who completed alpha-theta brain wave training (Peniston & Kulkosky, 1989). What accounts for these changes? The current theories behind alpha-theta brainwave training are documented in an excellent article by Jonathan D. Cowan, Ph.D. in the Megabrain Report: The Journal of Mind Technology (Vol. 2, No. 3). Cowan suggests that the power of the imagery instructions given prior to the EEG training, in which patients rehearse new intentions and positive alternatives, should not be underestimated. "These images of personal change are experienced in a relaxed state, followed closely by the effect induced by alpha-theta biofeedback, which is usually very pleasant. This forms an association between the images and pleasant effect which is repeated 30 times throughout the course of therapy.... The power of [the] ... training may be partly due to inputting images and suggestions in such a way that they bypass the conscious mind, thereby benefiting from the lack of interference from adult disbelief and disempowerment." Other researchers have used a treatment protocol similar to Peniston's with equally good results. A couple of clinicians have added another twist � patients do the EEG brainwave training together in a group setting. The supportive element in group process has long been a key factor in alcoholism treatment (12-step and other groups). But the use of brain wave training in a group has raised interesting questions about whether people can actually influence each other's brain waves. Certainly "mob psychology" indicates that people are capable of thinking and acting quite differently while in a group than when alone. But how that relates to brain chemistry remains a mystery. In the mind-body self-regulation groups run by the Center for Mind-Body Medicine, participants regularly use biofeedback techniques together in the group. The program's director, Mary Lee Esty, believes the group practice has a supportive, reinforcing effect that enhances individual, at-home practice. The impact of biofeedback and mind-body self-regulation techniques within a small group setting merits further study. The Center plans to begin such a research project in 1996. Increasingly sophisticated measurement devices may expand biofeedback's possibilities in the future. For example, a number of biofeedback experts, including Esty in Washington, D.C., are pioneering a new form of EEG training that uses light stimulation to increase the range and variability of patients' dominant brain frequencies. The treatment is proving successful with trauma victims whose brains have gotten "stuck" in a pattern of predominantly slow waves. EEG slowing is associated with symptoms such as anxiety, depression, irritability, fatigue, hyperactivity, distractibility, mood swings, confusion and disorganization. More and more, biofeedback researchers are discovering that the key to wellness is not figuring out how to achieve a perpetual "theta state." The key is brain flexibility, or as Cowan writes, teaching [a person] "to perceive and control a number of different transitions among his own unique state-contexts, which differ among themselves in the amounts of each of these rhythms that they produce. Says Esty, "The objective is balance." Clearly, the entire field of biofeedback is as ripe for new discovery as it was 30 years ago. According to Alternative Medicine: Expanding Medical Horizons, biofeedback deserves more broad clinical trials on large patient populations to determine its effectiveness. "A major reason why many patients like biofeedback training is that...it puts them in charge, giving them a sense of mastery and self-reliance over their illness and health," states the report to the National Institutes of Health. "Such an attitude may play a crucial role in the lower health care costs seen in patients after learning biofeedback skills." Auditory Beats in the Brain by Gerald Oster Scientific American, October 1973 Slow modulations called binaural beats are perceived when tones of different frequency are presented separately to each ear. The sensation may show how certain sounds are processed in the brain. If two tuning forks of slightly different pitch are struck simultaneously, the resulting sound waxes and wanes periodically. The modulations are referred to as beats; their frequency is equal to the difference between the frequencies of the two original tones. Binaural beats have been widely regarded as a mere curiosity. A recent textbook on hearing does not mention them at all. Yet the measurement of binaural beats can explain the processes by which sounds are located -- a crucial aspect of perception. It is possible that hormonally induced physiological behavior changes may be made apparent by measuring the binaural-beat spectrum. The Mind Revealed by Marcia Barinaga SCIENCE, Vol. 249 (1989) Some neuroscientists think that recently discovered oscillations of electrical potential at 40 hertz hold the key to how the brain assembles sense impressions into a single object. Has Wolf Singer uncovered the cellular basis of consciousness? Some neuroscientists think he may have, although Singer himself stops short of such a bold claim. It was in his recording that Singer noticed that, for short periods of less than half a second, the field potential was oscillating--alternately rising and dipping--with a frequency of 40 hertz. Those oscillations reflected a synchronous, repeating pattern of current flow into the neurons in the vicinity of the electrode. And since such an ion flow often triggers an action potential, that meant that many of those neurons must be firing action potentials together, in brief phase-locked synchrony. "We think of consciousness as occurring in different ways," Crick says. "You can be consc...
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