Specific versus placebo effects in biofeedback training: A critical lay perspective

Recent interchanges on the question of how to evaluate biofeedback have been cast in terms of a researcher versus clinician dichotomy. This tends to make the arguments ad hominem and focuses attention on minutiae that are of limited general interest. Accordingly, one purpose of the present paper is to state the specific-effects approach to biofeedback evaluation from a critical lay, rather than a research, perspective. The logic of the specific-effects approach to treatment evaluation is first illustrated by a hypothetical example (the Minefield Parable), and it is then suggested that the approach is appropriate for the evaluation of any treatment, be it physical, psychological, or some complex combination. The other purpose of the paper is to further clarify the specific-effects position by responding to some difficulties that have been raised by critics of the position. Some of these difficulties are based on misrepresentations of the position, while others are genuine. However, even for the genuine difficulties, practical solutions are available. The paper concludes that the question of whether a particular class of treatments works is one that is properly raised by the intelligent consumer, and that, for the answer to that question, only the facts, based on adequately controlled clinical studies, will do.The preparation of this paper was supported by a grant from the National Science and Engineering Research Council of Canada. I am indebted to Hal Scher and Donna Shulhan for comments on an earlier draft.     

Problems inherent in assessing biofeedback efficacy studies

This paper discusses some of the problems involved in drawing conclusions across studies about the efficacy of biofeedback. It focuses on biofeedback for the treatment of hypertension, but the same difficulties arise when considering the effect of biofeedback in other disorders. Large multicenter studies using the same inclusion and exclusion criteria, biofeedback protocol, and methodology are badly needed if biofeedback practitioners are ever going to demonstrate the real effectiveness of biofeedback.     

Specific versus placebo effects in biofeedback: Some brief back-to-basics considerations

Following the semantic complexities raised in earlier papers, this paper seeks to return to some of the more basic considerations arising from the preceding discussion. A critical part of the context of that discussion is the increasingly important issue of accountability. In this context, the citing of supportive studies is not enough, one must also be able to justify the logical relevance of those studies. The discussion therefore turns of the logic of treatment evaluation, which must be treated as objectively as possible. Also critical is the distinction between the question of whether an effect is present and the question of what the source of that question might be. In the quest for treatment evaluation, only the former question is important. However, this quest is one that is in the interest of researchers, clinicians, and consumers, for all of whom only the facts will do.The preparation of this paper was supported by grants from the National Science and Engineering Research Council of Canada to both authors. We are indebted to Hal Scher for comments on an earlier draft.     

Specific versus placebo effects in biofeedback: some brief back-to-basics considerations

Following the semantic complexities raised in earlier papers, this paper seeks to return to some of the more basic considerations arising from the preceding discussion. A critical part of the context of that discussion is the increasingly important issue of accountability. In this context, the citing of supportive studies is not enough; one must also be able to justify the logical relevance of those studies. The discussion therefore turns on the logic of treatment evaluation, which must be treated as objectively as possible. Also critical is the distinction between the question of whether an effect is present and the question of what the source of that question might be. In the quest for treatment evaluation, only the former question is important. However, this quest is one that is in the interest of researchers, clinicians, and consumers, for all of whom only the facts will do.     

Nocturnal biofeedback for nocturnal bruxism

Reports have appeared recently describing the successful reduction of nocturnal bruxism through nocturnal biofeedback. These claims of effective treatments rest mainly on the use of a single index of integrated masseter EMG levels as a measure of bruxism and are based only on short-term effects. The present study was conducted to provide a more rigorous evaluation of the effectiveness of noctural biofeedback for nocturnal bruxism through the use of all-night polysomnographic recordings. The results from multiple indices of bruxism are internally consistent and indicate that simple nocturnal biofeedback does not appear to be effective in reducing nocturnal bruxing. Recommendations are made for a more comprehensive approach to the treatment of nocturnal bruxism.     

An alternative perspective on biofeedback efficacy studies: a reply to Steiner and Dince

Clinical applications of biofeedback have proliferated and considerable lore surrounding the application of these techniques has evolved. Many assertions about the effectiveness of biofeedback training are based on findings of the least well-controlled studies, while many of the better controlled studies have failed to show that biofeedback directly mediates target symptoms or is superior to other treatments. Steiner and Dince (1981) suggest that the failure of these controlled studies is primarily attributable to methodological deficiencies. We believe that the question of whether or not there is a specific effect of biofeedback training is still frequently confused with the question of whether or not the treatment package as a whole has therapeutic value. Biofeedback is often therapeutic; however, evidence is often lacking that its effectiveness is due to biofeedback-trained changes in a target physiological process.     

Specific effects and biofeedback versus biofeedback-assisted self-regulation training

In any field, clear and logical conceptualizations are the basis of accurate models----correct research design----correct results----correct conclusions----advancement in the field. Faulty conceptualizations----faulty models----faulty research design----faulty results----faulty conclusions----confusion. In analyzing the conceptualizations of "biofeedback" as expressed by John Furedy (1987) in, "Specific versus Placebo Effects in Biofeedback Training: A Critical Lay Perspective," we focus on two issues: Does biofeedback have a treatment effect? Is biofeedback necessary for the training effect? In discussing issue (1) we describe the multiple meanings of "biofeedback" and raise the fundamental question: Is biofeedback a treatment? We argue that faulty conceptualizations of clinical biofeedback (1) assume that the treatment in clinical biofeedback is "biofeedback" with specific effects, (2) assume that the scientific basis of biofeedback is dependent upon demonstrations of these specific effects through double-blind design that distinguish "specific" from "placebo effects," and (3) trivialize clinical research by attempting to determine the usefulness of biofeedback information--usefulness that is already understood logically by professionals and consumers and demonstrated by clinical studies in the laboratory and in the clinic. We further argue that accurate conceptualizations of clinical biofeedback (1) identify self-regulation skills as the treatment with specific effects of physiological change and symptom reduction, and (2) describe the use of information from biofeedback instruments as scientific verification of self-regulation skills. Finally, the scientific basis of clinical biofeedback is based on (1) evidence from experimental and clinical control studies that have demonstrated the effectiveness of self-regulation skills for symptom alleviation, and (2) the use of biofeedback instruments to verify the acquisition of self-regulatory skills, thus fulfilling the scientific dictum of verifiability.     

The behavioral treatment of Raynaud's disease: A review

Raynaud's disease is a peripheral vascular system disorder characterized by episodes of vasoconstriction in the hands and feet resulting in a lowering of skin temperature and pain. Recent studies are reviewed that focus on the behavioral treatment of Raynaud's disease—in particular, biofeedback and autogenic training. Methodological problems and other difficulties include the measurement of skin temperature, schedules of reinforcement/feedback, and characteristics of the experimenter and subject. Studies in this area indicate some promise for certain behavioral interventions, especially finger temperature biofeedback under cold stress conditions. On the other hand, further research is needed to clarify the mechanisms, especially that of vasodilation, and the applications of temperature biofeedback, as well as the role of attitudinal, interpersonal, and cognitive factors.     

The behavioral treatment of Raynaud's disease: a review

Raynaud's disease is a peripheral vascular system disorder characterized by episodes of vasoconstriction in the hands and feet resulting in a lowering of skin temperature and pain. Recent studies are reviewed that focus on the behavioral treatment of Raynaud's disease--in particular, biofeedback and autogenic training. Methodological problems and other difficulties include the measurement of skin temperature, schedules of reinforcement/feedback, and characteristics of the experimenter and subject. Studies in this area indicate some promise for certain behavioral interventions, especially finger temperature biofeedback under cold stress conditions. On the other hand, further research is needed to clarify the mechanisms, especially that of vasodilation, and the applications of temperature biofeedback, as well as the role of attitudinal, interpersonal, and cognitive factors.     

Specific effects and biofeedback versus biofeedback-assisted self-regulation training

In any field, clear and logical conceptualizations are the basis of accurate models → correct research design → correct results → correct conclusions → advancement in the field. Faulty conceptualizations → faulty models → faulty research design → faulty results → faulty conclusions → confusion. In analyzing the conceptualizations of “biofeedback” as expressed by John Furedy (1987) in, “Specific versus Placebo Effects in Biofeedback Training: A Critical Lay Perspective,” we focus on two issues: Does biofeedback have a treatment effect? Is biofeedback necessary for the training effect? In discussing issue (1) we describe the multiple meanings of “biofeedback” and raise the fundamental question: Is biofeedback a treatment? We argue that faulty conceptualizations of clinical biofeedback (1) assume that the treatment in clinical biofeedback is “biofeedback” with specific effects, (2) assume that the scientific basis of biofeedback is dependent upon demonstrations of these specific effects through double-blind designs that distinguish “specific” from “placebo effects,” and (3) trivialize clinical research by attempting to determine the usefulness of biofeedback information — usefulness that is already understood logically by professionals and consumers and demonstrated by clinical studies in the laboratory and in the clinic. We further argue that accurate conceptualizations of clinical biofeedback (1) identify self-regulation skills as the treatment with specific effects of physiological change and symptom reduction, and (2) describe the use of information from biofeedback instruments as scientific verification of self-regulation skills. Finally, the scientific basis of clinical biofeedback is based on (1) evidence from experimental and clinical control studies that have demonstrated the effectiveness of self-regulation skills for symptom alleviation, and (2) the use of biofeedback instruments to verify the acquisition of self-regulatory skills, thus fulfilling the scientific dictum of verifiability.     

Biofeedback theory and application in allied health

The implementation of biofeedback procedures represents a new approach to clinical management of speech disorders. Thus far, results of experiments utilizing biofeedback techniques have suggested positive effects in the remediation of speech disorders. The purpose of this paper is to provide the reader with the principles of biofeedback; to survey areas of clinical application including voice, fluency, and other clinical disorders; and to explore potential applications of biofeedback procedures for the speech and language pathologist.     

Biofeedback for Psychiatric Disorders: A Systematic Review

Biofeedback potentially provides non-invasive, effective psychophysiological interventions for psychiatric disorders. The encompassing purpose of this review was to establish how biofeedback interventions have been used to treat select psychiatric disorders [anxiety, autistic spectrum disorders, depression, dissociation, eating disorders, schizophrenia and psychoses] to date and provide a useful reference for consultation by clinicians and researchers planning to administer a biofeedback treatment. A systematic search of EMBASE, MEDLINE, PsycINFO, and WOK databases and hand searches in Applied Psychophysiology and Biofeedback, and Journal of Neurotherapy, identified 227 articles; 63 of which are included within this review. Electroencephalographic neurofeedback constituted the most investigated modality (31.7 %). Anxiety disorders were the most commonly treated (68.3 %). Multi-modal biofeedback appeared most effective in significantly ameliorating symptoms, suggesting that targeting more than one physiological modality for bio-regulation increases therapeutic efficacy. Overall, 80.9 % of articles reported some level of clinical amelioration related to biofeedback exposure, 65.0 % to a statistically significant (p < .05) level of symptom reduction based on reported standardized clinical parameters. Although the heterogeneity of the included studies warrants caution before explicit efficacy statements can be made. Further development of standardized controlled methodological protocols tailored for specific disorders and guidelines to generate comprehensive reports may contribute towards establishing the value of biofeedback interventions within mainstream psychiatry.     

Comparing treatment-induced changes for k independent samples of paired observations

In a recent paper, MARASCUILO [19] has provided an asymptotic solution to the important question on how to test for differences in change parameters when paired observation of binary type (+, -) have been made on two or more independent samples of individuals. In this article, an alternative approach is presented implying asymptotic as well as exact tests for changes. They are based on pre-post test designs from clinical research and allow for controlled evaluation of one treatment modality as well as for comparing 2 or more than 2 treatment modalities. The rationale of the tests is based on McNEMARS [21] test for paired binary observations in one, two, or k samples.     

Ethical and practice considerations for biofeedback therapists in the treatment of urinary incontinence

The treatment of incontinence presents many unique issues for biofeedback therapists that are routine for professionals in fields such as nursing or medicine. Although, all professional practice is guided by ethical standards, the unique circumstances encountered during biofeedback treatments for this disorder warrant the development of specific guidelines. This is true whether insertable or surface EMG devices are used. Therefore, the purpose of this article is to propose a set of ethical guidelines for biofeedback therapists. The intended audience includes professionals such as psychologists, clinical psychophysiologists, and other mental health-care providers who use biofeedback techniques. These are not formally endorsed by any professional organizations (e.g., APA, AAPB) at this time. Ethical considerations include proper medical evaluation, informed consent, patient instruction, disrobing, nonerotic physical contact, patient safety, and patient satisfaction.     

The “How and Why” of Group Biofeedback for Chronic Disease Management

Biofeedback has been shown to have some level of efficacy for the treatment of a number of chronic medical conditions; however, individualized biofeedback treatment is not always feasible. While group- based interventions are growing in practice due to numerous advantages, the dearth of research examining the efficacy of Group Biofeedback (GBF) suggests that this treatment modality may not be commonly utilized. Thus, the current paper highlights some advantages and constructively addresses potential challenges of utilizing GBF. Obstacles specific to GBF include equipment for participants, need for support staffing, and billing. However, the potential benefits are numerous, and pertain to cost-effectiveness, improved patient access, and additive benefits specific to group-based treatment. We offer a six-session GBF protocol to be used to guide future clinical work in this area. We hope that through the ideas and protocol presented in this paper, biofeedback practitioners will be more inclined to implement GBF.     

Approximations, idealizations and 'experiments' at the physics-biology interface

This paper, which is based on recent empirical research at the University of Leeds, the University of Edinburgh, and the University of Bristol, presents two difficulties which arise when condensed matter physicists interact with molecular biologists: (1) the former use models which appear to be too coarse-grained, approximate and/or idealized to serve a useful scientific purpose to the latter; and (2) the latter have a rather narrower view of what counts as an experiment, particularly when it comes to computer simulations, than the former. It argues that these findings are related; that computer simulations are considered to be undeserving of experimental status, by molecular biologists, precisely because of the idealizations and approximations that they involve. The complexity of biological systems is a key factor. The paper concludes by critically examining whether the new research programme of 'systems biology' offers a genuine alternative to the modelling strategies used by physicists. It argues that it does not.     

An interdisciplinary approach to the treatment of a hyperfunctional voice disorder

The purpose of this article is to describe the treatment of a 45-year-old male with a hyperfunctional voice disorder by a biofeedback therapist and a speech-language pathologist. The interdisciplinary approach to the treatment of this voice disorder involved the combined use of traditional voice therapy techniques and EMG biofeedback procedures together with cognitive behavioral therapy. Voice therapy was facilitated through the use of a computer-based, speech-monitoring system. The remediation of this voice disorder was attributed to the collaborative efforts of two professionals representing diverse professional training and treatment protocols. The results showed reductions in muscle activity in the infrahyoid and laryngeal areas as well as improved use of proper breathing and voicing onset behaviors. Follow-up at 10 and 15 months posttreatment intervals indicated that the client had retained all target voice skills and the tension reduction/biofeedback skills. Results suggest that interdisciplinary, collaborative efforts using biofeedback and voice therapy can prove beneficial in the treatment of hyperfunctional voice disorders.Note: Neither author has been compensated in any way for the use of the CAFET System nor does either have any financial interest in the company.     

Biofeedback training: offerings, plans, and some attitudes in graduate schools and internships

Graduate schools and APA-approved internships in North America were surveyed to determine the type and extent of biofeedback training, additional biofeedback training planned, requirements considered to be a minimum necessary before beginning clinical practice of biofeedback, when biofeedback is considered an appropriate application, and whether biofeedback is considered a "passing fad" in clinical practice. Questionnaires were returned by 56% of the graduate schools and 54% of the internships, and revealed training in 58% and 67% respectively. Training in biofeedback procedures appears to be growing, and most graduate schools and internships think that biofeedback is not a passing fad in clinical practice. Training emphases vary considerably across graduate schools and internships, with some schools and internships excluding theory and/or practice and/or research from their instruction. The results are discussed in relation to the question of determining which procedures to include in future instruction.     

Effects of Biofeedback in Phonatory Disorders and Phonatory Performance: A Systematic Literature Review

The purpose of this article was to systematically review the literature on the effects of biofeedback therapy in the domain of phonatory disorders and phonatory performance, using studies in peer-reviewed journals. An extensive definition of biofeedback is given and its place in voice treatment is defined. Eighteen group or case studies or reports considering the effects of electromyographic, laryngoscopic and acoustic biofeedback in dysphonic patients (hyperfunctional voice disorders, hypofunctional voice disorders, psychogenic voice disorder, laryngeal trauma, total laryngectomy, vocal cord dysfunction) and participants with normal voices are included and an analysis of procedure as well as research design and results is presented. The usefulness of biofeedback in phonatory disorders and performance was to be interpreted based on tendencies, since there is a lack of randomized controlled efficacy studies. In only 3 of 18 studies (16.7%) did biofeedback therapy fail to improve voice quality or not result in better results than other forms of therapy. Recommendations for improved methodologies are made, which include the use of acoustic voice quality parameters.     

A components analysis of biofeedback in the treatment of fecal incontinence

Fecal incontinence is a socially disabling symptom for which rectosphincteric biofeedback has been reported to be dramatically effective. The most commonly employed biofeedback procedure incorporates three separate and potentially effective components: (1) exercise of the external sphincter muscle, (2) training in discrimination of rectal sensations, and (3) training synchrony of the internal and external sphincter responses. This paper reports the results of single case experiments employed with eight incontinent patients to examine the contributions of each of these components. All eight patients improved, but only one required the biofeedback procedure as it was originally described. Three responded to sensory discrimination training, one to exercise training, and one to the training of synchronous sphincteric responses; three recovered independently of the effects of biofeedback. Despite the achievement of continence, the rectosphincteric reflexes following treatment continued to be abnormal in every case. These findings suggest that the character of the external sphincter response to rectal distension is an unreliable index of sphincter function and that exercise and sensory discrimination training procedures are effective for some cases of fecal incontinence.The work described in this paper was supported by Grant No. MA 6241 from the Medical Research Council of Canada.