Clinical Applications of Biofeedback: Implications for Psychiatry NORMAN MARCUS, M.D. Clinical Coordinator ofPsychiatr’ic Skills Residency Program in Social Medicine Montefiore Hospital and Medical Center Bronx, New York
The field became progressively more useful and accessible as advancing technology overcame deficiencies in accuracy of measurements,3 and as electronic mmiaturization led to the development of portable units that could be sold at significantly decreased prices compared with the cumbersome older units.46 Biofeedback has been defined by Barbara Brown, self-described midwife attending its birth, as simply the feedback of biological information to the person whose body it is. For the reader who has somehow
GILBERT LEVIN, PH.D. Associate Professor of Psychiatry and Community Health Department of Psychiatry Albert Einstein College of Medicine Bronx, New York
“
‘ ‘
escaped
The authors briefly describe biofeedback techniques such as EMG feedback, temperature feedback, and heart rate feedback, along with reports from the literature about their application to specific problems such as subvocalization while reading, Raynaud’s disease, cardiac arrhythmias, and epilepsy. Many clinical applications of biofeedback are aimed at inducing relaxation, a state that has important psychotherapeutic potential. The authors suggest that biofeedback could be used to reduce a patient’s general level of arousal or as an adjunct to behavior therapy or insight therapy. While there have been no reports in the literature of any harmful effects secondary to feedback training, the authors caution that some patients may respond negatively to an objectively measured state of relaxation. #{149}Biofeedback treatment approaches to a variety of clinical symptoms have been tentatively added to the armamentarium of the clinician. Some innovative practitioners were using biofeedback equipment in the 1950s,’ but popular interest in and enthusiasm for the field did not emerge until the late 1960s, when the lay press reported on the experiments in which subjects “learned voluntary control over their EEC patterns.”2 Dr. Marcus also is assistant professor of community health and clinical instructor of psychiatry at the Albert Einstein College of Medicine. His address at Monteflore Hospital is 111 East 210 Street, Bronx, New York 10467. 1 C. B. Whatmore and D. R. Kohli, The Physiopathology and Treatment of Functional Disorders, Grune & Stratton, New York City, 1974. 2j Kamiya, “Conscious Control of Brain Waves,” Psychology Today, Vol. 1, April 1968, pp. 55-60.
HOSPITAL
& COMMUNITY
PSYCHIATRY
the
flood
of publicity
about
the
biofeedback
phenomenon, a somewhat more detailed description may be useful: biofeedback is an educational method in which ordinarily unavailable information about variations in an individual’s own bodily processes is presented continuously to him, enabling him to make adjustments in those bodily processes that would have been impossible or difficult without access to the information fed back. For example, a blindfolded man fails to learn how to hit the target with a dart because he lacks information about the results of his previous efforts. When the blindfold is removed, the feedback loop is closed, and the man becomes capable of learning. After each miss he modifies his toss until, through trial and error, he hits the target-and perhaps even the bull’s-eye. In recent years this self-corrective feedback principle has been used to modify a wide range of body processes. Reports of new clinical applications are now emerging at a very rapid rate. Many of these applications are aimed at reducing tension or inducing relaxation. This orientation is particularly true of clinical applications used in psychiatric or psychological clinics. 3 W. I. Grossman and H. Weiner, ‘ Some Factors Affecting the Reliability of Surface Electromyography,” Psychosomatic Medicine, Vol. 28, January-February 1966, pp. 78-83. 4 R. L. Schwitzgebel and J. D. Rugh, ‘Of Bread, Circuses, and Alpha Machines,” American Psychologist, Vol. 30, March 1975, pp. 363-370. ‘D. A. Paskewitz, “Biofeedback Instrumentation: Soldering Closed the Loop,” American Psychologist, Vol. 30, March 1975, pp. 371-378. #{149} D. Girdano, Buying Biofeedback,” in Biofeedback and Self Control, T. X. Barber et a!., editors, Aldine, Chicago, 1976. B. B. Brown, New Mind, New Body, Harper & Row, New York City, 1974.
VOLUME
28 NUMBER
1 JANUARY
1977
21
The studies we have examined lead us to two conclusions: the induction of relaxation has important psychotherapeutic potential, and biofeedback is only one of several methods that may be used to induce relaxation. Before discussing these points, however, we will address three questions pertaining to biofeedback: What clinical applications have been tried? What effects have been achieved? What are the implications for psychiatric practice? Biofeedback modalities have been reported in the treatment of a wide range of dysfunctional states. The practical clinical importance to the psychiatrist of many of these approaches would appear to be his knowledge that such treatment exists rather than his actual implementation of that treatment. We will briefly describe how the biofeedback technique is used and what
reports
have
been
published
about
its use with
specific
problems. EMGfeedback. In procedures using electromyographic (EMG) feedback, electrodes are placed on the subject’s skin overlying the muscle or muscle group to be trained. The electrical activity is converted into a sound that the subject can hear through a speaker or headphones. The sound-clicks or a tone-varies directly with the amount of electrical activity emanating from the muscle; for example, a greater number of clicks or a higher pitched tone indicates more muscle tension. Brudny and others8 and Cleeland9 have described the successful treatment of patients with torticollis through the use of EMG feedback. Hardyck, Petrinovich, and Ellsworth’#{176} and Aarons11 trained subjects who subvocalized while reading to relax their laryngeal muscles and thus eliminate subvocalization. The decrease in subvocalization was accompanied by an increase in reading speed and comprehension. J ohnson and Carton12 and Brudny’3 have used EMG feedback to train neurologically damaged patients to increase their muscle activity in partially injured musdes that were clinically nonfunctional. In this exercise the patients were asked to concentrate on increasing the number of clicks or the pitch of the tone. Temperature feedback. A heat-sensitive electrode is taped to the part of the body where temperature change is desired. In visual feedback, the temperature
registers on a dial; the needle indicator moves to the left when the temperature drops and to the right when it rises. In audio feedback, the pitch of a sound tone goes down as the temperature rises and goes up as the temperature falls. Raynaud’s disease has been treated by teaching the subject to warm his extremities.” Heart rate and rhythm feedback. A subject is connected to an EKG machine that is modified to turn on a green light when his heart is beating too slowly, a red light when it is beating too fast, and an amber light when it is beating in the desired range. Engel’5 and Weiss’6 have worked with subjects who have cardiac arrhythmias. The subjects were monitored to determine what heart-rate range seemed to promote the appearance of abnormal beats (generally premature ventricular contractions); subjects then were trained to either increase or decrease their heart rate so it would not fall in the dangerous range. Similar studies have been done by other investigators in different laboratories; the results seem promising but not conclusive. EEGfeedback. An EEC is set up so that a sound will be produced when the subject’s electrical brain waves reach the frequency range desired. Sterman has re-
ported
B. B. Grynbaum, by Feedback and Rehabilitation,
and Display Vol.
J.
Korein, “Spasmodic of EMG,” Archives 55, September 1974,
Tortiof Physpp. 403-
ical Medicine 408. #{149} C. S. Cleeland, ‘ Behavioral Techniques in the Modification of Spasmodic Torticollis,” Neurology, Vol. 23, November 1973, pp. 1241-1247. 10 C. D. Hardyck, L F. Petrinovich, and D. W. Ellsworth, ‘Feedback of Speech Muscle Activity During Silent Reading, Science, Vol. 154, December 16, 1966, pp. 1467-1468. ‘ L. Aarons, “Subvocalization: Aural and EMG Feedback in Reading,” Perceptual and Motor Skills, Vol. 33, August 1971, pp. 271-306. 12 H. E. Johnson and W. H. Garton, Muscle Re-education in Hemiplegia by Use of Electromyographic Device,” Archives of Physical Medicine and Rehabilitation, Vol. 54, July 1973, pp. 320-322. 1 J Brudny et a!., EMG Feedback Therapy: Review of Treatment of 114 Patients,” Archives of Physical Medicine and Rehabilitation, Vol. 57, February 1976, pp. 55-61.
22
HOSPITAL
& COMMUNITY
PSYCHIATRY
treatment
of various
epileptic
disorders
the process of enhancing the subject’s produca 12-to-14 cycles-per-second rhythm over the sensory motor cortex. Although the study group is small -four patients-the results strongly suggest that patients develop the capacity to control seizure activity when they can produce greater amounts of sensorimotor rhythm (SMR).’7 Hauri reports using SMR training in the treatment of nondepressed subjects who have frequent awakenings from sleep.’8 Anal sphincter control. A double balloon tied around a hollow metal capsule is placed at the internal and external sphmncters. Polyethylene tubing leads from each balloon to a mechanical transducer so that pressures in the balloons can be translated into a polygraphic readout that the subject can watch. Engel and others’9 reported on six patients with rectal incontinence secondary to impairment of their external rectal sphincter. Four of the patients had normal control and the other two significant improvement over 14
#{149} J. Brudny, collis: Treatment
on the
through tion of
R. S. Surwit,
‘
Biofeedback:
A Possible
Treatment
for Raynaud’s
Disease,” Seminars in Psychiatry. Vol. 5, November 1973, pp. 483490. 15 B. T. Engel, “Clinical Applications of Operant Conditioning Techniques in the Control of the Cardiac Arrhythmias,” Seminars in Psychiatry, Vol. 5, November 1973, pp. 433-438. 10 T. Weiss and B. T. Engel, ‘ ‘ Operant Conditioning of Heart Rate in Patients With Premature Ventricular Contractions,’ ‘ Psychosomatic Medicine, Vol. 33, July-August 1971, pp. 301-321. 17 M. B. Sterman, ‘Neurophysiologic and Clinical Studies of Sensorimotor EEC Biofeedback Training: Some Effects on Epilepsy,” Seminars in Psychiatry, Vol. 5, November 1973, pp. 507-525. 1$ P. Hauri, P. J. Phelps, and J. B. Jordan, “Biofeedback as a Treatment for Insomnia,” Proceedings of the Biofeedback Research Society, Denver, February 1976, p. 34. ‘ B. T. Engel, P. Nikoomanesh, and M. M. Schuster, “Operant Conditioning of Rectosphincteric Responses in the Treatment of Fecal Incontinence,” New England Journal of Medicine, Vol. 290, March 21, 1974, pp. 646-649.
the
follow-up
five
years.
period,
PSYCHOSOMATIC
which
lasted
from
six months
to
DISEASES
Psychiatrists have been involved in the actual treatment of a number of psychosomatic and functional disorders. Although the hopes generated by Franz Alexander’s early work were not realized, some patients with classical psychosomatic disease are seen, and others seek help for coincidental neurotic conflicts. The one classical psychosomatic disease that has been treated with biofeedback and has attracted atten-
tion
recently
is essential
labile
hypertension.
The
ap-
proach here is multifaceted; it reflects two major ayenues of approach. One method focuses on the technique of lowering the level of arousal and the other
focuses
specifically
and
exclusively
on
the
function
being trained. An example of the latter is Neil Miller’s report of the treatment of a woman with essential hypertension. He used a device that measured her blood pressure and fed back an audio signal when the desired decrease in blood pressure was achieved.2#{176} Patel did not directly feed back blood pressure readings, but rather taught relaxation and meditative techniques and supplemented the training with galvanic skin response (GSR) and EMG feedback.21’22 Pelletier argues that patients with psychosomatic disorders are good candidates for biofeedback treatment because they have already mastered control over their autonomic nervous system, only in the wrong direction. He describes a flexible method of using EEC, EMC, CSR, and temperature feedback, depending on the parameter that manifests abnormal’ values, and of moving within this group when resistance to the development of further control develops.28 ‘ ‘
FUNCTIONAL
‘
DISORDERS
Patients with functional disorders, or disease states that can only be described as an unexplained hyper or hypo activity of the system in question, are frequently referred to the psychiatrist for consultation or for treatment. Diagnoses found may include conversion hysteria, somatic depressive equivalent, and psychosis with somatic delusions. Behavior therapy has been used to treat such conditions, as has traditional psychotherapy, 20
N. Miller,
Current
Status
“Learning
of Visceral
of Physiological
and
Glandular
Psychology:
Readings,
Responses,”
D. Singh California, 1972,
in
and
C. T. Morgan, editors, Brooks-Cole, Monterey, pp. 245-250. 21 C. Patel and W. R. North, “Randomised Controlled Trial of Yoga and Biofeedback in Management of Hypertension,” Lancel, Vol. 2, July 19, 1975, pp. 93-95. 22 C. Patel, “Twelve-Month Follow-up of Yoga and Biofeedback in Management of Hypertension,” Lancet, Vol. 1, January 11, 1975, p.
62-64. 2$ K. Clinical Society,
Pelletier, ‘ Diagnosis, Procedures, Biofeedback,” Proceedings of Denver, January 1975, p. 30.
the
and Phenomenology of Biofeedback Research
analysis, and chemotherapy. Biofeedback investigators also have reported on their work in this area. Perhaps the psychiatrist can be more helpful to his somatically oriented colleagues through the refinement and incorporation of some of the following biofeedback techniques. EMG feedback. Tension headaches have been treated by a number of investigators.24’25 The data from the published reports indicate that there is a reduction in headache activity coincident to the acquired ability to relax the frontalis muscles and the surrounding musdes of the forehead. However, the most successful subjects have been those who practiced relaxation regularly at home. The relative contributions of EMG training and daily relaxation periods have not been delineated. Temperature feedback. Some investigators have reported that they have been able to train migraine patients to warm their hands and thus to decrease or eliminate the occurrence of migraine headache episodes,2828 Turin has presented evidence to demonstrate an increase in headache activity with hand cooling and a decrease with hand warming.29 Penile tumescence. A recent article has demonstrated the efficacy of biofeedback in teaching normal subjects to voluntarily control penile erection.8#{176} A strain gauge is placed around the penis and is attached to an integrator that is programmed to turn on a light when the desired change in penile circumference is reached. It remains to be demonstrated if this procedure can be applied to cases of impotence. Gastrointestinal function feedback. An electronic stethoscope amplifies bowel sounds picked up over the abdomen. The subject learns to decrease the frequency and intensity of the sounds. Furman reports on the successful treatment of functional diarrhea using bowel-sound feedback. His five cases include three patients on low-residue diets, one on an intermittent low-residue diet, and one following no dietary restrictions at all. All but one had been medicated in varying degrees over extended periods of time. Medication consisted of anticholinergics, ataractics, antispasmodics, and opiates. Frequency of bowel move24 T. H. Budzynski ache: A Controlled 35, November-December 25 I Wickramasekera,
et al., “ EMG Biofeedback and Outcome Study,” Psychosomatic 1973, pp. 484-496. “ Electromyographic Feedback
Tension Medicine, Training
HeadVol. and
Tension Clinical
Headache: Preliminary Observations,” American Journal of Hypnosis, Vol. 15, October 1972, pp. 83-85. 20 J D. Sargent, E. E. Green, and E. D. Walters, ‘ Preliminary Report on the Use of Autogenic Feedback Training in the Treatment of Migraine and Tension Headaches,” Psychosomatic Medicine, Vol. 35, March-April 1973, pp. 129-135. 27 E. Peper, ‘ Frontiers of Clinical Biofeedback,” in Biofeedback: Behavioral Medicine, L. Birk, editor, Grune & Stratton, New York City, 1973. I. Wickramasekera, Temperature Feedback for the Control of Migraine,” Journal of Behavior Therapy and Experimental Psychiatry, Vol. 4, June 1975, pp. 343-345. A. Turin and W. C. Johnson, “Biofeedback Therapy for Migraine Headaches,” Archives of General Psychiatry, in press. 3#{176} R. C. Rosen, D. Shapiro, and G. E. Schwartz, Voluntary Control of Penile Tumescence,” Psychosomatic Medicine, Vol. 37, November-December 1975, pp. 479-483.
VOLUME
28 NUMBER
1 JANUARY
1977
23
Biofeedback is an educational method in which ordinarily unavailable information about variations in an individual’s own bodily processes is presented continuously to him, enabling him to adjust those processes. ments varied from four to 15 per day. All patients reported exacerbation of their symptoms at times of stress, and all had resigned themselves to their problem and adapted their daily lives around it.31 PSYCHOTHERAPEUTIC
APPLICATIONS
If we think of biofeedback as a means of inducing relaxation, then it has a broad range of potential applications to psychotherapy. While numerous anecdotal reports have appeared, very few systematic studies have been carried out. Since investigation along these lines appears warranted, we offer the following suggestions. Relaxation as a principal means of treatment. Regular elicitation of the relaxation response appears to have generalized positive consequences for the organism.8285 If we extend the notion of psychotherapy to include primary prevention, then a case could be made for trying biofeedback techniques as a means of reducing the general level of arousal, instead of such other methods as meditation, progressive relaxation, and autogenic training. However, since these other methods require no hardware or other paraphernalia, they would seem to be preferable unless future research demonstrates an unequivocal advantage for biofeedback. Frontalis EMC was tried as the sole treatment for patients suffering from chronic undifferentiated anxiety, with negative results.3 In the late 1960s reports of alpha wave learning were published37 and claims were made that the mere production of alpha would produce a positive mood alteration. Later studies, however, 31 5, Furman, Intestinal Biofeedback in Functional Diarrhea: A Preliminary Report,” in Biofeedback and Self-Control, L. V. DiCara et a!., editors, Aldine, Chicago, 1974. 3#{176} H. Benson, The Relaxation Response, Morrow, New York City, 1975. 3#{176} B. C. Glueck and C. F. Stroebel, “Biofeedback and Meditation in the Treatment of Psychiatric Illnesses,” Comprehensive Psychiatry, Vol. 16, July-August 1975, pp. 303-321. 3#{176} E. Jacobson, Relaxation, Thomas, Springfield, Illinois, 1970. 3#{176} H. Schultz and W. Luthe, Autogenic Training, Grune & Stratton, New York City, 1959. 3#{176} M. Raskin, C. Johnson, and J. W. Rondestvedt, ‘Chronic Anxiety Treated by Feedback-Induced Muscle Relaxation: A Pilot Study,” Archives of General Psychiatry, Vol. 28, February 1973, pp. 263-267. “ J. Vanisya, ‘Operant Control of the EEC Alpha Rhythm and Some of Its Reported Effects on Consciousness,” in Biofeedback and Self Control, T. X. Barber et a!., editors, Aldine, Chicago, 1971.
24
HOSPITAL
& COMMUNITY
PSYCHIATRY
demonstrated that the alpha state did not necessarily produce a desirable mood.38 Lynch and others suggest that alpha learning does not occur at all, but that we are seeing the gradual return to baseline production in the reported experiments.39 That is, the subjects progressively habituate to the experimental procedure so that their brain wave production at the end of an experiment only reflects what would have occurred in a nonexperimental relaxed state. Hardt has recently found that alpha learning occurs in stages.4#{176}Thus the flattening out of the curve representing alpha production over the duration of Lynch’s experiment may be just a function of the short time span of the experiment. Whatever the case may be, direct clinical applicability of alpha training has yet to be demonstrated. While improvements in technology might make it possible to treat anxiety as well as other specific psychiatric disorders solely through biofeedback, this seems improbable and a less promising application than some of the lines suggested below. Relaxation as an adjunct to other forms of therapy. Many practitioners of systematic desensitization and other forms of behavioral therapy rely heavily on the induction of relaxation in their therapeutic work. Once the stimulus that triggers the patient’s undesired behavior has been identified, relaxation can be induced and the stimulus introduced at a low level of intensity. Over the course of therapy, the patient learns to maintam a relaxed state even in the presence of strong stimulation. Biofeedback monitoring may have special advantages in this work because it permits objective measurement of the level of arousal under different levels of stimulus intensity. Carrington and Ephron advocate the combined use of psychotherapy and meditation as a treatment method. They cite numerous benefits of this procedure and offer some interesting speculations about the therapeutic mechanisms underlying meditation. They instruct their patients to meditate for a period of time before each therapeutic session, and observe that this procedure seems to have a general unblocking effect on the therapy.4’ A pre-session period of relaxation might promote freer verbalization and thus facilitate therapeutic movement in a wide range of therapeutic approaches. Biofeedback as an adjunct to insight therapy. The potential of biofeedback to promote self-awareness has only begun to be explored and warrants further inU T. A. Travis, C. Y. Kondo, and J. R. Knott, “ Alpha Enhancement Research: A Review,” Biological Psychiatry, Vol. 10, February 1975, pp. 69-80. 3#{176} J. J. Lynch, D. A. Paskewitz, and M. T. Orne, “Some Factors in the Feedback Control of Human Alpha Rhythm,” Psychosomatic Medicine, Vol. 36, September-October 1974, pp. 399-410. 4#{176} J. Hardt, “The Ups and Downs of Learning Alpha Feedback,” Proceedings of the Biofeedback Research Society, Denver, January 1975, p. 118. 41 P. Carrington and H. Ephron, “Meditation as an Adjunct to Psychotherapy,” in New Dimensions in Psychiatry: A World View, S. Arieti and C. Chrzanowski, editors, Wiley, New York City, 1975, pp. 261-292.
vestigation. Toomin reports using GSR monitoring in psychotherapy for the purpose of assisting the patient to gain access to blocked affect. A patient who shows no GSR response while discussing emotionally charged material may gain greater access to the affect associated with the material if he can learn to produce more appropriate visceral responses. Toomin uses biofeedback training techniques to teach more appropriate affective responding, and then works with the newly available material using more conventional psychotherapeutic methods.42 Investigators treating psychosomatic disorders, including headaches, have noted that unless repressed material-frequently rage or sadness-is expressed and worked through, there is poor learning of muscle control and little or no lasting symptom relief.43’44 In an analogous fashion, one of the authors of this paper (NM), has used EMC monitoring to concretize specific defensive patterns. In one case, a patient who was burdened with almost continuous preconscious ideation of a hostile and paranoid nature was able to realize this only after he observed the high ambient level of his own muscle tension on the EMC monitor. That recognition helped the patient develop a more positive orientation toward the world. The use of instrumentation may be especially helpful with obsessive patients who may be more apt to accept an observation that is substantiated by a reading from a machine. SOME
PRECAUTIONS
There have been no reports in the literature of any harmful effects secondary to feedback training. One would not expect a procedure that produces relaxation’ to cause injury to a patient. However, some patients may respond negatively to an objectively measured state of relaxation. An example is a patient who was not aware of his high level of ambient muscle tension. When he was placed on an EMG feedback device and was instructed to keep the sound low in pitch, he reduced the tension in his frontalis muscle and contiguous muscle groups. He suddenly experienced overwhelming anxiety and jumped up from the couch. What probably happened was that the excessive muscle activity had been serving as a means of binding anxiety. As the muscle tension was reduced, the anxiety became conscious. Thus we have a somatic analogue to the analysis of intrapsychic defenses with the production of anxiety states. In both situations the practitioner must help the patient cope with the anxiety. ‘ ‘
‘
42
M.
Toomin
and
H. Toomin,
“Psychodynamic
Correlates
Paradoxically Invariant GSR,” Proceedings of the Biofeedback search Society, Denver, January 1975, p. 31. C. S. Adler and S. M. Adler, “The Pragmatic Application Biofeedback to Headaches: A Five-Year Clinical Follow-up,” ceedings of the Biofeedback Research Society, Denver, January
In some cases relaxation may jeopardize patients with stress-related diseases. Many patients with diabetes mellitus who are under stress will require more insulin to control their blood sugar. A diabetic patient taught some types of relaxation may decrease his need for insulin; if he is not closely monitored during the period of relaxation training, he may develop hypoglycemic episodes, and, in some cases, fall into insulin coma.45’46 Patients receiving antihypertensive medications are in a similar situation. Methods to induce generalized states of relaxation frequently affect all the parameters that are associated with the level of arousal (GSR, muscle tension, skin temperature, EEC patterns, heart rate, respiration, blood pressure).47 When we are using biofeedback, we are usually working with only one parameter. Since all the functions of the body are interrelated, we cannot totally predict what effect lowering or altering one function may have on other functions. For example, if we were training someone with high blood pressure to lower his CSR response, what might this do to his blood pressure? Is the excessive production of CSR (or the inappropriately small response) a protective homeostatic mechanism? As the use of biofeedback spreads, clinicians will have to address themselves to these questions. There are no regulations at the present time governing the use of biofeedback equipment. Recently, however, an FDA panel ruled that biofeedback machinery will require labeling that indicates that it is a medical therapeutic device. Practitioners interested in biofeedback training can attend numerous workshops that are publicized in the professional journals or can buy teaching tapes that have been prepared by experts in the field.481 45 J. Fowler and T. Budzynski, “The Effects of an EMG Biofeedback Relaxation Program on the Control of Diabetes in One Patient,” Proceedings of the Biofeedback Research Society, Denver, February 1974, p. 9. 4#{176}Schultz and Luthe, op. cit. M. A. Wenger and B. K. Bagchi, ‘Studies of Autonomic Functions in Practitioners of Yoga in India,” Behavioral Science, Vol. 6, October 1961, pp. 312-323. 4#{176}The Biofeedback Research Society in Denver publishes a complete bibliography of the field as well as an annual proceedings of research conventions and a journal. The society’s mailing address is University of Colorado Medical Center, 4200 East Ninth Avenue, Denver, Colorado 80220.
of the Reof Pro1976,
p.2. “R. Gallon and S. Padnes, “EMG Biofeedback and Response,” Proceedings of the Biofeedback Research ver, January 1976, p. 24.
the Relaxation Society, Den-
VOLUME
28 NUMBER
1 JANUARY
1977
25
The field became progressively more useful and accessible as advancing technology overcame deficiencies in accuracy of measurements,3 and as electronic mmiaturization led to the development of portable units that could be sold at significantly decreased prices compared with the cumbersome older units.46 Biofeedback has been defined by Barbara Brown, self-described midwife attending its birth, as simply the feedback of biological information to the person whose body it is. For the reader who has somehow
GILBERT LEVIN, PH.D. Associate Professor of Psychiatry and Community Health Department of Psychiatry Albert Einstein College of Medicine Bronx, New York
“
‘ ‘
escaped
The authors briefly describe biofeedback techniques such as EMG feedback, temperature feedback, and heart rate feedback, along with reports from the literature about their application to specific problems such as subvocalization while reading, Raynaud’s disease, cardiac arrhythmias, and epilepsy. Many clinical applications of biofeedback are aimed at inducing relaxation, a state that has important psychotherapeutic potential. The authors suggest that biofeedback could be used to reduce a patient’s general level of arousal or as an adjunct to behavior therapy or insight therapy. While there have been no reports in the literature of any harmful effects secondary to feedback training, the authors caution that some patients may respond negatively to an objectively measured state of relaxation. #{149}Biofeedback treatment approaches to a variety of clinical symptoms have been tentatively added to the armamentarium of the clinician. Some innovative practitioners were using biofeedback equipment in the 1950s,’ but popular interest in and enthusiasm for the field did not emerge until the late 1960s, when the lay press reported on the experiments in which subjects “learned voluntary control over their EEC patterns.”2 Dr. Marcus also is assistant professor of community health and clinical instructor of psychiatry at the Albert Einstein College of Medicine. His address at Monteflore Hospital is 111 East 210 Street, Bronx, New York 10467. 1 C. B. Whatmore and D. R. Kohli, The Physiopathology and Treatment of Functional Disorders, Grune & Stratton, New York City, 1974. 2j Kamiya, “Conscious Control of Brain Waves,” Psychology Today, Vol. 1, April 1968, pp. 55-60.
HOSPITAL
& COMMUNITY
PSYCHIATRY
the
flood
of publicity
about
the
biofeedback
phenomenon, a somewhat more detailed description may be useful: biofeedback is an educational method in which ordinarily unavailable information about variations in an individual’s own bodily processes is presented continuously to him, enabling him to make adjustments in those bodily processes that would have been impossible or difficult without access to the information fed back. For example, a blindfolded man fails to learn how to hit the target with a dart because he lacks information about the results of his previous efforts. When the blindfold is removed, the feedback loop is closed, and the man becomes capable of learning. After each miss he modifies his toss until, through trial and error, he hits the target-and perhaps even the bull’s-eye. In recent years this self-corrective feedback principle has been used to modify a wide range of body processes. Reports of new clinical applications are now emerging at a very rapid rate. Many of these applications are aimed at reducing tension or inducing relaxation. This orientation is particularly true of clinical applications used in psychiatric or psychological clinics. 3 W. I. Grossman and H. Weiner, ‘ Some Factors Affecting the Reliability of Surface Electromyography,” Psychosomatic Medicine, Vol. 28, January-February 1966, pp. 78-83. 4 R. L. Schwitzgebel and J. D. Rugh, ‘Of Bread, Circuses, and Alpha Machines,” American Psychologist, Vol. 30, March 1975, pp. 363-370. ‘D. A. Paskewitz, “Biofeedback Instrumentation: Soldering Closed the Loop,” American Psychologist, Vol. 30, March 1975, pp. 371-378. #{149} D. Girdano, Buying Biofeedback,” in Biofeedback and Self Control, T. X. Barber et a!., editors, Aldine, Chicago, 1976. B. B. Brown, New Mind, New Body, Harper & Row, New York City, 1974.
VOLUME
28 NUMBER
1 JANUARY
1977
21
The studies we have examined lead us to two conclusions: the induction of relaxation has important psychotherapeutic potential, and biofeedback is only one of several methods that may be used to induce relaxation. Before discussing these points, however, we will address three questions pertaining to biofeedback: What clinical applications have been tried? What effects have been achieved? What are the implications for psychiatric practice? Biofeedback modalities have been reported in the treatment of a wide range of dysfunctional states. The practical clinical importance to the psychiatrist of many of these approaches would appear to be his knowledge that such treatment exists rather than his actual implementation of that treatment. We will briefly describe how the biofeedback technique is used and what
reports
have
been
published
about
its use with
specific
problems. EMGfeedback. In procedures using electromyographic (EMG) feedback, electrodes are placed on the subject’s skin overlying the muscle or muscle group to be trained. The electrical activity is converted into a sound that the subject can hear through a speaker or headphones. The sound-clicks or a tone-varies directly with the amount of electrical activity emanating from the muscle; for example, a greater number of clicks or a higher pitched tone indicates more muscle tension. Brudny and others8 and Cleeland9 have described the successful treatment of patients with torticollis through the use of EMG feedback. Hardyck, Petrinovich, and Ellsworth’#{176} and Aarons11 trained subjects who subvocalized while reading to relax their laryngeal muscles and thus eliminate subvocalization. The decrease in subvocalization was accompanied by an increase in reading speed and comprehension. J ohnson and Carton12 and Brudny’3 have used EMG feedback to train neurologically damaged patients to increase their muscle activity in partially injured musdes that were clinically nonfunctional. In this exercise the patients were asked to concentrate on increasing the number of clicks or the pitch of the tone. Temperature feedback. A heat-sensitive electrode is taped to the part of the body where temperature change is desired. In visual feedback, the temperature
registers on a dial; the needle indicator moves to the left when the temperature drops and to the right when it rises. In audio feedback, the pitch of a sound tone goes down as the temperature rises and goes up as the temperature falls. Raynaud’s disease has been treated by teaching the subject to warm his extremities.” Heart rate and rhythm feedback. A subject is connected to an EKG machine that is modified to turn on a green light when his heart is beating too slowly, a red light when it is beating too fast, and an amber light when it is beating in the desired range. Engel’5 and Weiss’6 have worked with subjects who have cardiac arrhythmias. The subjects were monitored to determine what heart-rate range seemed to promote the appearance of abnormal beats (generally premature ventricular contractions); subjects then were trained to either increase or decrease their heart rate so it would not fall in the dangerous range. Similar studies have been done by other investigators in different laboratories; the results seem promising but not conclusive. EEGfeedback. An EEC is set up so that a sound will be produced when the subject’s electrical brain waves reach the frequency range desired. Sterman has re-
ported
B. B. Grynbaum, by Feedback and Rehabilitation,
and Display Vol.
J.
Korein, “Spasmodic of EMG,” Archives 55, September 1974,
Tortiof Physpp. 403-
ical Medicine 408. #{149} C. S. Cleeland, ‘ Behavioral Techniques in the Modification of Spasmodic Torticollis,” Neurology, Vol. 23, November 1973, pp. 1241-1247. 10 C. D. Hardyck, L F. Petrinovich, and D. W. Ellsworth, ‘Feedback of Speech Muscle Activity During Silent Reading, Science, Vol. 154, December 16, 1966, pp. 1467-1468. ‘ L. Aarons, “Subvocalization: Aural and EMG Feedback in Reading,” Perceptual and Motor Skills, Vol. 33, August 1971, pp. 271-306. 12 H. E. Johnson and W. H. Garton, Muscle Re-education in Hemiplegia by Use of Electromyographic Device,” Archives of Physical Medicine and Rehabilitation, Vol. 54, July 1973, pp. 320-322. 1 J Brudny et a!., EMG Feedback Therapy: Review of Treatment of 114 Patients,” Archives of Physical Medicine and Rehabilitation, Vol. 57, February 1976, pp. 55-61.
22
HOSPITAL
& COMMUNITY
PSYCHIATRY
treatment
of various
epileptic
disorders
the process of enhancing the subject’s produca 12-to-14 cycles-per-second rhythm over the sensory motor cortex. Although the study group is small -four patients-the results strongly suggest that patients develop the capacity to control seizure activity when they can produce greater amounts of sensorimotor rhythm (SMR).’7 Hauri reports using SMR training in the treatment of nondepressed subjects who have frequent awakenings from sleep.’8 Anal sphincter control. A double balloon tied around a hollow metal capsule is placed at the internal and external sphmncters. Polyethylene tubing leads from each balloon to a mechanical transducer so that pressures in the balloons can be translated into a polygraphic readout that the subject can watch. Engel and others’9 reported on six patients with rectal incontinence secondary to impairment of their external rectal sphincter. Four of the patients had normal control and the other two significant improvement over 14
#{149} J. Brudny, collis: Treatment
on the
through tion of
R. S. Surwit,
‘
Biofeedback:
A Possible
Treatment
for Raynaud’s
Disease,” Seminars in Psychiatry. Vol. 5, November 1973, pp. 483490. 15 B. T. Engel, “Clinical Applications of Operant Conditioning Techniques in the Control of the Cardiac Arrhythmias,” Seminars in Psychiatry, Vol. 5, November 1973, pp. 433-438. 10 T. Weiss and B. T. Engel, ‘ ‘ Operant Conditioning of Heart Rate in Patients With Premature Ventricular Contractions,’ ‘ Psychosomatic Medicine, Vol. 33, July-August 1971, pp. 301-321. 17 M. B. Sterman, ‘Neurophysiologic and Clinical Studies of Sensorimotor EEC Biofeedback Training: Some Effects on Epilepsy,” Seminars in Psychiatry, Vol. 5, November 1973, pp. 507-525. 1$ P. Hauri, P. J. Phelps, and J. B. Jordan, “Biofeedback as a Treatment for Insomnia,” Proceedings of the Biofeedback Research Society, Denver, February 1976, p. 34. ‘ B. T. Engel, P. Nikoomanesh, and M. M. Schuster, “Operant Conditioning of Rectosphincteric Responses in the Treatment of Fecal Incontinence,” New England Journal of Medicine, Vol. 290, March 21, 1974, pp. 646-649.
the
follow-up
five
years.
period,
PSYCHOSOMATIC
which
lasted
from
six months
to
DISEASES
Psychiatrists have been involved in the actual treatment of a number of psychosomatic and functional disorders. Although the hopes generated by Franz Alexander’s early work were not realized, some patients with classical psychosomatic disease are seen, and others seek help for coincidental neurotic conflicts. The one classical psychosomatic disease that has been treated with biofeedback and has attracted atten-
tion
recently
is essential
labile
hypertension.
The
ap-
proach here is multifaceted; it reflects two major ayenues of approach. One method focuses on the technique of lowering the level of arousal and the other
focuses
specifically
and
exclusively
on
the
function
being trained. An example of the latter is Neil Miller’s report of the treatment of a woman with essential hypertension. He used a device that measured her blood pressure and fed back an audio signal when the desired decrease in blood pressure was achieved.2#{176} Patel did not directly feed back blood pressure readings, but rather taught relaxation and meditative techniques and supplemented the training with galvanic skin response (GSR) and EMG feedback.21’22 Pelletier argues that patients with psychosomatic disorders are good candidates for biofeedback treatment because they have already mastered control over their autonomic nervous system, only in the wrong direction. He describes a flexible method of using EEC, EMC, CSR, and temperature feedback, depending on the parameter that manifests abnormal’ values, and of moving within this group when resistance to the development of further control develops.28 ‘ ‘
FUNCTIONAL
‘
DISORDERS
Patients with functional disorders, or disease states that can only be described as an unexplained hyper or hypo activity of the system in question, are frequently referred to the psychiatrist for consultation or for treatment. Diagnoses found may include conversion hysteria, somatic depressive equivalent, and psychosis with somatic delusions. Behavior therapy has been used to treat such conditions, as has traditional psychotherapy, 20
N. Miller,
Current
Status
“Learning
of Visceral
of Physiological
and
Glandular
Psychology:
Readings,
Responses,”
D. Singh California, 1972,
in
and
C. T. Morgan, editors, Brooks-Cole, Monterey, pp. 245-250. 21 C. Patel and W. R. North, “Randomised Controlled Trial of Yoga and Biofeedback in Management of Hypertension,” Lancel, Vol. 2, July 19, 1975, pp. 93-95. 22 C. Patel, “Twelve-Month Follow-up of Yoga and Biofeedback in Management of Hypertension,” Lancet, Vol. 1, January 11, 1975, p.
62-64. 2$ K. Clinical Society,
Pelletier, ‘ Diagnosis, Procedures, Biofeedback,” Proceedings of Denver, January 1975, p. 30.
the
and Phenomenology of Biofeedback Research
analysis, and chemotherapy. Biofeedback investigators also have reported on their work in this area. Perhaps the psychiatrist can be more helpful to his somatically oriented colleagues through the refinement and incorporation of some of the following biofeedback techniques. EMG feedback. Tension headaches have been treated by a number of investigators.24’25 The data from the published reports indicate that there is a reduction in headache activity coincident to the acquired ability to relax the frontalis muscles and the surrounding musdes of the forehead. However, the most successful subjects have been those who practiced relaxation regularly at home. The relative contributions of EMG training and daily relaxation periods have not been delineated. Temperature feedback. Some investigators have reported that they have been able to train migraine patients to warm their hands and thus to decrease or eliminate the occurrence of migraine headache episodes,2828 Turin has presented evidence to demonstrate an increase in headache activity with hand cooling and a decrease with hand warming.29 Penile tumescence. A recent article has demonstrated the efficacy of biofeedback in teaching normal subjects to voluntarily control penile erection.8#{176} A strain gauge is placed around the penis and is attached to an integrator that is programmed to turn on a light when the desired change in penile circumference is reached. It remains to be demonstrated if this procedure can be applied to cases of impotence. Gastrointestinal function feedback. An electronic stethoscope amplifies bowel sounds picked up over the abdomen. The subject learns to decrease the frequency and intensity of the sounds. Furman reports on the successful treatment of functional diarrhea using bowel-sound feedback. His five cases include three patients on low-residue diets, one on an intermittent low-residue diet, and one following no dietary restrictions at all. All but one had been medicated in varying degrees over extended periods of time. Medication consisted of anticholinergics, ataractics, antispasmodics, and opiates. Frequency of bowel move24 T. H. Budzynski ache: A Controlled 35, November-December 25 I Wickramasekera,
et al., “ EMG Biofeedback and Outcome Study,” Psychosomatic 1973, pp. 484-496. “ Electromyographic Feedback
Tension Medicine, Training
HeadVol. and
Tension Clinical
Headache: Preliminary Observations,” American Journal of Hypnosis, Vol. 15, October 1972, pp. 83-85. 20 J D. Sargent, E. E. Green, and E. D. Walters, ‘ Preliminary Report on the Use of Autogenic Feedback Training in the Treatment of Migraine and Tension Headaches,” Psychosomatic Medicine, Vol. 35, March-April 1973, pp. 129-135. 27 E. Peper, ‘ Frontiers of Clinical Biofeedback,” in Biofeedback: Behavioral Medicine, L. Birk, editor, Grune & Stratton, New York City, 1973. I. Wickramasekera, Temperature Feedback for the Control of Migraine,” Journal of Behavior Therapy and Experimental Psychiatry, Vol. 4, June 1975, pp. 343-345. A. Turin and W. C. Johnson, “Biofeedback Therapy for Migraine Headaches,” Archives of General Psychiatry, in press. 3#{176} R. C. Rosen, D. Shapiro, and G. E. Schwartz, Voluntary Control of Penile Tumescence,” Psychosomatic Medicine, Vol. 37, November-December 1975, pp. 479-483.
VOLUME
28 NUMBER
1 JANUARY
1977
23
Biofeedback is an educational method in which ordinarily unavailable information about variations in an individual’s own bodily processes is presented continuously to him, enabling him to adjust those processes. ments varied from four to 15 per day. All patients reported exacerbation of their symptoms at times of stress, and all had resigned themselves to their problem and adapted their daily lives around it.31 PSYCHOTHERAPEUTIC
APPLICATIONS
If we think of biofeedback as a means of inducing relaxation, then it has a broad range of potential applications to psychotherapy. While numerous anecdotal reports have appeared, very few systematic studies have been carried out. Since investigation along these lines appears warranted, we offer the following suggestions. Relaxation as a principal means of treatment. Regular elicitation of the relaxation response appears to have generalized positive consequences for the organism.8285 If we extend the notion of psychotherapy to include primary prevention, then a case could be made for trying biofeedback techniques as a means of reducing the general level of arousal, instead of such other methods as meditation, progressive relaxation, and autogenic training. However, since these other methods require no hardware or other paraphernalia, they would seem to be preferable unless future research demonstrates an unequivocal advantage for biofeedback. Frontalis EMC was tried as the sole treatment for patients suffering from chronic undifferentiated anxiety, with negative results.3 In the late 1960s reports of alpha wave learning were published37 and claims were made that the mere production of alpha would produce a positive mood alteration. Later studies, however, 31 5, Furman, Intestinal Biofeedback in Functional Diarrhea: A Preliminary Report,” in Biofeedback and Self-Control, L. V. DiCara et a!., editors, Aldine, Chicago, 1974. 3#{176} H. Benson, The Relaxation Response, Morrow, New York City, 1975. 3#{176} B. C. Glueck and C. F. Stroebel, “Biofeedback and Meditation in the Treatment of Psychiatric Illnesses,” Comprehensive Psychiatry, Vol. 16, July-August 1975, pp. 303-321. 3#{176} E. Jacobson, Relaxation, Thomas, Springfield, Illinois, 1970. 3#{176} H. Schultz and W. Luthe, Autogenic Training, Grune & Stratton, New York City, 1959. 3#{176} M. Raskin, C. Johnson, and J. W. Rondestvedt, ‘Chronic Anxiety Treated by Feedback-Induced Muscle Relaxation: A Pilot Study,” Archives of General Psychiatry, Vol. 28, February 1973, pp. 263-267. “ J. Vanisya, ‘Operant Control of the EEC Alpha Rhythm and Some of Its Reported Effects on Consciousness,” in Biofeedback and Self Control, T. X. Barber et a!., editors, Aldine, Chicago, 1971.
24
HOSPITAL
& COMMUNITY
PSYCHIATRY
demonstrated that the alpha state did not necessarily produce a desirable mood.38 Lynch and others suggest that alpha learning does not occur at all, but that we are seeing the gradual return to baseline production in the reported experiments.39 That is, the subjects progressively habituate to the experimental procedure so that their brain wave production at the end of an experiment only reflects what would have occurred in a nonexperimental relaxed state. Hardt has recently found that alpha learning occurs in stages.4#{176}Thus the flattening out of the curve representing alpha production over the duration of Lynch’s experiment may be just a function of the short time span of the experiment. Whatever the case may be, direct clinical applicability of alpha training has yet to be demonstrated. While improvements in technology might make it possible to treat anxiety as well as other specific psychiatric disorders solely through biofeedback, this seems improbable and a less promising application than some of the lines suggested below. Relaxation as an adjunct to other forms of therapy. Many practitioners of systematic desensitization and other forms of behavioral therapy rely heavily on the induction of relaxation in their therapeutic work. Once the stimulus that triggers the patient’s undesired behavior has been identified, relaxation can be induced and the stimulus introduced at a low level of intensity. Over the course of therapy, the patient learns to maintam a relaxed state even in the presence of strong stimulation. Biofeedback monitoring may have special advantages in this work because it permits objective measurement of the level of arousal under different levels of stimulus intensity. Carrington and Ephron advocate the combined use of psychotherapy and meditation as a treatment method. They cite numerous benefits of this procedure and offer some interesting speculations about the therapeutic mechanisms underlying meditation. They instruct their patients to meditate for a period of time before each therapeutic session, and observe that this procedure seems to have a general unblocking effect on the therapy.4’ A pre-session period of relaxation might promote freer verbalization and thus facilitate therapeutic movement in a wide range of therapeutic approaches. Biofeedback as an adjunct to insight therapy. The potential of biofeedback to promote self-awareness has only begun to be explored and warrants further inU T. A. Travis, C. Y. Kondo, and J. R. Knott, “ Alpha Enhancement Research: A Review,” Biological Psychiatry, Vol. 10, February 1975, pp. 69-80. 3#{176} J. J. Lynch, D. A. Paskewitz, and M. T. Orne, “Some Factors in the Feedback Control of Human Alpha Rhythm,” Psychosomatic Medicine, Vol. 36, September-October 1974, pp. 399-410. 4#{176} J. Hardt, “The Ups and Downs of Learning Alpha Feedback,” Proceedings of the Biofeedback Research Society, Denver, January 1975, p. 118. 41 P. Carrington and H. Ephron, “Meditation as an Adjunct to Psychotherapy,” in New Dimensions in Psychiatry: A World View, S. Arieti and C. Chrzanowski, editors, Wiley, New York City, 1975, pp. 261-292.
vestigation. Toomin reports using GSR monitoring in psychotherapy for the purpose of assisting the patient to gain access to blocked affect. A patient who shows no GSR response while discussing emotionally charged material may gain greater access to the affect associated with the material if he can learn to produce more appropriate visceral responses. Toomin uses biofeedback training techniques to teach more appropriate affective responding, and then works with the newly available material using more conventional psychotherapeutic methods.42 Investigators treating psychosomatic disorders, including headaches, have noted that unless repressed material-frequently rage or sadness-is expressed and worked through, there is poor learning of muscle control and little or no lasting symptom relief.43’44 In an analogous fashion, one of the authors of this paper (NM), has used EMC monitoring to concretize specific defensive patterns. In one case, a patient who was burdened with almost continuous preconscious ideation of a hostile and paranoid nature was able to realize this only after he observed the high ambient level of his own muscle tension on the EMC monitor. That recognition helped the patient develop a more positive orientation toward the world. The use of instrumentation may be especially helpful with obsessive patients who may be more apt to accept an observation that is substantiated by a reading from a machine. SOME
PRECAUTIONS
There have been no reports in the literature of any harmful effects secondary to feedback training. One would not expect a procedure that produces relaxation’ to cause injury to a patient. However, some patients may respond negatively to an objectively measured state of relaxation. An example is a patient who was not aware of his high level of ambient muscle tension. When he was placed on an EMG feedback device and was instructed to keep the sound low in pitch, he reduced the tension in his frontalis muscle and contiguous muscle groups. He suddenly experienced overwhelming anxiety and jumped up from the couch. What probably happened was that the excessive muscle activity had been serving as a means of binding anxiety. As the muscle tension was reduced, the anxiety became conscious. Thus we have a somatic analogue to the analysis of intrapsychic defenses with the production of anxiety states. In both situations the practitioner must help the patient cope with the anxiety. ‘ ‘
‘
42
M.
Toomin
and
H. Toomin,
“Psychodynamic
Correlates
Paradoxically Invariant GSR,” Proceedings of the Biofeedback search Society, Denver, January 1975, p. 31. C. S. Adler and S. M. Adler, “The Pragmatic Application Biofeedback to Headaches: A Five-Year Clinical Follow-up,” ceedings of the Biofeedback Research Society, Denver, January
In some cases relaxation may jeopardize patients with stress-related diseases. Many patients with diabetes mellitus who are under stress will require more insulin to control their blood sugar. A diabetic patient taught some types of relaxation may decrease his need for insulin; if he is not closely monitored during the period of relaxation training, he may develop hypoglycemic episodes, and, in some cases, fall into insulin coma.45’46 Patients receiving antihypertensive medications are in a similar situation. Methods to induce generalized states of relaxation frequently affect all the parameters that are associated with the level of arousal (GSR, muscle tension, skin temperature, EEC patterns, heart rate, respiration, blood pressure).47 When we are using biofeedback, we are usually working with only one parameter. Since all the functions of the body are interrelated, we cannot totally predict what effect lowering or altering one function may have on other functions. For example, if we were training someone with high blood pressure to lower his CSR response, what might this do to his blood pressure? Is the excessive production of CSR (or the inappropriately small response) a protective homeostatic mechanism? As the use of biofeedback spreads, clinicians will have to address themselves to these questions. There are no regulations at the present time governing the use of biofeedback equipment. Recently, however, an FDA panel ruled that biofeedback machinery will require labeling that indicates that it is a medical therapeutic device. Practitioners interested in biofeedback training can attend numerous workshops that are publicized in the professional journals or can buy teaching tapes that have been prepared by experts in the field.481 45 J. Fowler and T. Budzynski, “The Effects of an EMG Biofeedback Relaxation Program on the Control of Diabetes in One Patient,” Proceedings of the Biofeedback Research Society, Denver, February 1974, p. 9. 4#{176}Schultz and Luthe, op. cit. M. A. Wenger and B. K. Bagchi, ‘Studies of Autonomic Functions in Practitioners of Yoga in India,” Behavioral Science, Vol. 6, October 1961, pp. 312-323. 4#{176}The Biofeedback Research Society in Denver publishes a complete bibliography of the field as well as an annual proceedings of research conventions and a journal. The society’s mailing address is University of Colorado Medical Center, 4200 East Ninth Avenue, Denver, Colorado 80220.
of the Reof Pro1976,
p.2. “R. Gallon and S. Padnes, “EMG Biofeedback and Response,” Proceedings of the Biofeedback Research ver, January 1976, p. 24.
the Relaxation Society, Den-
VOLUME
28 NUMBER
1 JANUARY
1977
25
