Respiratory Sinus Arrhythmia Versus Neck/Trapezius EMG and Incentive Inspirometry Biofeedback for Asthma: A Pilot Study

This pilot study compared biofeedback to increase respiratory sinus arrhythmia (RSA) with EMG and incentive inspirometry biofeedback in asthmatic adults. A three-group design (Waiting List Control n = 5, RSA biofeedback n = 6, and EMG biofeedback n = 6) was used. Six sessions of training were given in each of the biofeedback groups. In each of three testing sessions, five min. of respiratory resistance and EKG were obtained before and after a 20-min biofeedback session. Additional five-min epochs of data were collected at the beginning and end of the biofeedback period (or, in the control group, self-relaxation). Decreases in respiratory impedance occurred only in the RSA biofeedback group. Traub-Hering-Mayer (THM) waves (.03-.12 Hz) in heart period increased significantly in amplitude during RSA biofeedback. Subjects did not report significantly more relaxation during EMG or RSA biofeedback than during the control condition. However, decreases in pulmonary impedance, across groups, were associated with increases in relaxation. The results are consistent with Vaschillo's theory that RSA biofeedback exercises homeostatic autonomic reflex mechanisms through increasing the amplitude of cardiac oscillations. However, deep breathing during RSA biofeedback is a possible alternate explanation.     

Change Mechanisms Associated with Combined Relaxation/EMG Biofeedback Training for Chronic Tension Headache

Therapeutic mechanisms hypothesized to underlie improvements in tension headache activity achieved with combined relaxation and eleclromyographic (EMG) biofeedback therapy were examined. These therapeutic mechanisms included (1) changes in EMG activity in frontal and trapezii muscles, (2) changes in central pain modulation as indexed by the duration of the second exteroceptive silent period (ES2), and (3) changes in headache locus of control and self-efficacy. Forty-four young adults with chronic tension-type headaches were assigned either to six sessions of relaxation and EMG biofeedback training (N = 30) or to an assessment only control group (N = 14) that required three assessment sessions. Measures of self-efficacy and locus of control were collected at pre- and posttreatment, and ES2 was evaluated at the beginning and end of the first, third, and lost session. EMG was monitored before, during, and following training trials. Relaxation/EMG biofeedback training effectively reduced headache activity: 51.7% of subjects who received relaxation/biofeedback therapy recorded at least a 50% reduction in headache activity following treatment, while controls failed to improve on any measure. Improvements in headache activity in treated subjects were correlated with increases in self-efficacy induced by biofeedback training but not with changes in EMG activity or in ES2 durations. These results provide additional support for the hypothesis that cognitive changes underlie the effectiveness of relaxation and biofeedback therapies, at least in young adult tension-type headache sufferers.     

Specific Muscle EMG Biofeedback for Hand Dystonia

Currently available therapies have only limited success in patients having hand dystonia (writer's cramp). We employed specific muscle EMG biofeedback (audio feedback of the EMG from proximal large muscles of the limb that show abnormally high activity during writing) in 10 of 13 consecutive patients (age, 19–62 years; all males) with a duration of illness from 6 months to 8 years. In three patients, biofeedback was not applicable due to lack of abnormal EMG values. Nine patients showed dystonic posture during writing and had hypertrophy of one or more large muscles of the dominant hand. The remaining four patients showed either involvement of small muscles or muscle wasting. Ten patients were given four or more sessions of EMG audio biofeedback from the proximal large limb muscles, which showed maximum EMG activity. They also practiced writing daily with the relaxed limb for 5 to 10 min. Nine patients showed improvement from 37 to 93% in handwriting, alleviation of discomfort, and pain (assessed on a visual analogue scale). One patient did not show any improvement. Thus EMG biofeedback improved the clinical and electromyographic picture in those patients with hand dystonia who showed EMG overactivity of proximal limb muscles during writing. This specific type of EMG biofeedback appears to be a promising tool for hand dystonia and might also be applied to other types of dystonias.     

Biofeedback modification of frontal EMG in normal subjects

We carried out a controlled study on the voluntary control of the frontalis muscle by biofeedback procedures employing 20 normal subjects. Subjects were randomly divided into two groups of 10: (1) the biofeedback group and (2) the control group. Each of the two groups received five training sessions of about 40 minutes' duration each on different days. The results obtained are as follows: (1) In the biofeedback group, mean EMG levels decreased progressively and markedly from 2.16µVp-p min in the first session to 1.54µVp-p min in the last session. On the contrary, the control group did not show constant decreases in EMG levels over sessions. (2) The changes in the heart rate did not correlate with the changes in EMG activity. (3) The changes in the respiratory rate correlated with the changes in EMG activity.     

The effect of frontal EMG biofeedback training on the behavior of children with activity-level problems

N=1 withdrawal designs were employed with three children evidencing activity-level problems. Tutoring sessions occurred daily over a 2 1/2-month period. Each child was reinforced for decreasing frontalis muscle tension during auditory feedback while working arithmetic problems. Feedback was faded while tension reduction reinforcement was maintained. These procedures were repeated with reinforcement for increasing, rather than decreasing, muscle tension. Frontal EMG level, percent time on task, and motoric activity rate were obtained during sessions. Parent ratings of problem behavior in the home were recorded daily. Biofeedback with reinforcement was effective in both raising and lowering muscle tension. Effects were maintained by reinforcement. Results suggest a direct relationship between tension and activity levels. Academic performance and problem behavior improved significantly with reductions in EMG activity, although individual exceptions to these findings were present. Results lend support to the efficacy of frontal EMG biofeedback training in reducing activity, increasing attention to an academic task, and reducing problem behaviors.     

Biofeedback modification of frontal EMG in normal subjects

We carried out a controlled study on the voluntary control of the frontalis muscle by biofeedback procedures employing 20 normal subjects. Subjects were randomly divided into two groups of 10: (1) the biofeedback group and (2) the control group. Each of the two groups received five training sessions of about 40 minutes' duration each on different days. The results obtained are as follows: (1) In the biofeedback group, mean EMG levels decreased progressively and markedly from 2. 16 muVp-p min the first session to 1.54 muVp-p min in the last session. On the contrary, the control group did not show constant decreases in EMG levels over sessions. (2) The changes in the heart rate did not correlate with the changes in EMG activity. (3) The changes in the respiratory rate correlated with the changes in EMG activity.     

Biofeedback training in frontalis muscle relaxation and enhancement of belief in personal control

The hypothesis that biofeedback training in frontalis muscle relaxation increases beliefs in internal (personal) locus of control was tested. Subjects were divided into two groups (internals and externals) based on Mirels' (1970) factor analyzedpersonal control subscale of Rotter's (1966) I-E Scale. Internal and external subjects were assigned randomly to one of three conditions: biofeedback (BF), false feedback (FF), or no feedback (NF). All subjects were measured on frontalis electromyographic (EMG) activity. Training consisted of three sessions spaced 1 week apart. Each session was comprised of a 5-minute baseline (nonfeedback) trial followed by a 20-minute experimental session. After each experimental session, subjects completed a questionnaire which assessed the extent to which they attributed their EMG performance to personal and environmental sources. After three sessions, subjects were posttested on the I-E Scale. Results indicated that subjects receiving BF reduced their EMG activity more than did subjects in either the FF or NF conditions, and this effect was maintained across all three sessions. Subjects who received BF shifted toward internal personal locus of control from pre- to posttesting, whereas no such change was found for either FF or NF subjects. Also, the relationship between BF training and change in personal locus of control was mediated by subjects attributing their EMG reduction more to personal effort than to properties of the task. Results are discussed in terms of the importance of contingent feedback as a determinant of cognitions of control.     

Biofeedback treatment of Raynaud's disease and phenomenon

Six Raynaud's disease and four Raynaud's phenomenon patients were treated with 12 sessions of finger temperature biofeedback. The mean frequency of vasospastic attacks was reduced to 7.5% of that reported during the pretreatment baseline and was maintained for a 1 year follow-up period. Significant control of digital temperature was demonstrated during laboratory training sessions. Raynaud's phenomenon patients showed significantly greater temperature increases during feedback periods than Raynaud's disease patients. Correlations between finger temperature and other physiological measures suggested that results could not be attributed to general physical relaxation. The role of imagery in self-control of digital temperature is considered.Portions of this paper were presented at the annual meeting of the Biofeedback Society of America, Albuquerque, March 1978.     

Reliability of Infrared Plethysmography in BVP Biofeedback Therapy and the Relevance for Clinical Application

Biofeedback methods are well established as behavioral techniques for the therapy of various psychophysiological diseases. The forms of feedback generally employed are muscle activity (electromyogram), skin temperature, brain activity (electroencephalogram), and vasomotoricity. The latter technique, which employs plethysmographic feedback, has been studied most extensively in the therapy of migraine (vasoconstriction training, blood volume pulse training). Although the clinical efficacy has been demonstrated in several studies, little is known about the psychometric properties of this technique. This study examined the intrasession and intersession reliability of the pulse volume amplitude (PVA). The results showed that the PVA measurements within a single biofeedback session were highly reliable. Repositioning of the probe within the session resulted in a lower correlation coefficient, but one that was still sizable and significant. The PVA values from different sessions were not reliable (or comparable).     

The use and utility of EMG biofeedback with chronic schizophrenic patients

This study examined the efficacy of muscle relaxation training via electromyographic (EMG) biofeedback from the frontalis and forearm extensor muscles of schizophrenic inpatients. Thirty chronically hospitalized patients were randomly assigned to one of three conditions: EMG biofeedback from the forearm extensor and frontalis muscles, progressive relaxation, and a control group. Treatment consisted of one session of orientation and baseline, and six sessions of training. The results indicated that the schizophrenic patients receiving EMG training had significantly lower EMG recordings than the progressive relaxation group, which, in turn, was significantly lower than the control group. Analyses of covariance on the Tension-Anxiety scale from the Profile of Mood States revealed no significant effects, while finger-tapping rates were significantly improved only for the arm receiving feedback training in the EMG group. On the Nurses Observation Scale for Inpatient Evaluation the biofeedback group significantly improved on the Social Competence and Social Interest factors.We would like to express our appreciation for the contributions the following people made to this project: Drs. Barry Smith, Robert Steele, Agnes Hartfield, Jeffrey Barth, Althea Wagman, and the late Harold Weiner; Earl Downs and the participating staff at Springfield State Hospital Center; and Robert Kline and Michael Kelley, who performed the data analyses. This research was supported in part by a grant from the Computer Science Center at the University of Maryland.     

Biofeedback and progressive relaxation treatment of sleep-onset insomnia

Previous research suggests that self-defined insomniacs are distinguished from normals by high levels of anxiety and physiological arousal, which might be mitigated by muscle relaxation. This study assessed the relative effects of frontal EMG biofeedback, progressive relaxation, and a placebo set of relaxation exercises on the sleep of 18 onset insomniacs. Each subject was trained in one of these three methods for six half-hour sessions and slept in the laboratory for two consecutive nights before and after training. The experimental groups demonstrated significant decreases in physiological activity during training while changes in the control group were minimal. Reductions in sleep-onset time were: biofeedback group, 29.66 minutes; progressive relaxation group, 22.92 minutes; control group, 2.79 minutes. The experimental groups improved significantly(p<.05) more than the control group, but did not differ from each other. No significant relationships between physiological levels and sleep-onset time were found, which suggests that muscle relaxation alone was not responsible for subjects' improvements. Since 20 minutes of daily practice were required to achieve an approximate 30-minute decrease in sleep-onset time, the practical utility of the methods is questioned.Portions of this paper were presented at the 15th Annual Meeting of the Association for the Psychophysiological Study of Sleep, Edinburgh, July, 1975, and at the 6th Annual Meeting, Biofeedback Research Society, Monterey, California, February, 1975.     

The use and utility of EMG biofeedback with chronic schizophrenic patients

This study examined the efficacy of muscle relaxation training via electromyographic (EMG) biofeedback from the frontalis and forearm extensor muscles of schizophrenic inpatients. Thirty chronically hospitalized patients were randomly assigned to one of three conditions: EMG biofeedback from the forearm extensor and frontalis muscles, progressive relaxation, and a control group. Treatment consisted of one session of orientation and baseline, and six sessions of training. The results indicated that the schizophrenic patients receiving EMG training had significantly lower EMG recordings than the progressive relaxation group, which, in turn, was significantly lower than the control group. Analyses of covariance on the Tension-Anxiety scale from the Profile of Mood States revealed no significant effects, while finger-tapping rates were significantly improved only for the arm receiving feedback training in the EMG group. On the Nurses Observation Scale for Inpatient Evaluation the biofeedback group significantly improved on the Social Competence and Social Interest factors.     

Expectancies of reinforcement control in biofeedback and cognitive performance

This study investigated the effects of expectancies concerning the controllability of outcomes in a biofeedback task. Forty-eight college undergraduates were subjects. Frontal (forehead) electromyographic (EMG) responses were measured during baseline (no treatment), pretreatment, and test sessions. During pretreatment, subjects were assigned to one of three groups. Using a fictitious blood vessel control task, the success group received false feedback and instructions that conveyed that outcomes had been successfully controlled. The failure group received feedback and instructions that conveyed that outcomes had not been controlled. A control group was given no specific task. During the subsequent test stage, all subjects were asked to reduce frontal muscle tension levels through relaxation while assisted with true EMG feedback. Relative to the success and control groups, EMG levels of the failure group reflected more rapid acquisition of frontal muscle relaxation. However, performance on a cognitive task was not affected by the pretreatment. It was concluded that expectancies generated during the false feedback pretreatment were related to later biofeedback performance. The results were discussed in terms of concepts of locus of control and theories of learned helplessness and reactance.A version of this paper was presented at the annual meeting of the Biofeedback Society of America, San Diego, 1979.     

The role of EMG awareness in EMG biofeedback learning

Underlying most research on biofeedback learning is a theoretical model of the processes involved. The current study tested a prediction from the Awareness Model: High initial EMG awareness should facilitate response control during EMG biofeedback training. Seventy-two undergraduates were assessed for forehead EMG awareness by asking them to produce target responses from 1.0 to 5.0 µV every 15 s for 16 trials. Based on this assessment, two groups (high and low awareness) were trained for 64 trials to produce these target levels with either EMG biofeedback, practice (no feedback), or noncontingent EMG feedback. A transfer task was identical to the initial assessment. During training, the biofeedback group deviated less from target than the practice and noncontingent groups. The biofeedback group was the only group to improve from initial EMG awareness activity. During transfer, only the low awareness biofeedback group remained below initial EMG awareness level. These findings can be interpreted in terms of the Two-Process Model.     

A preliminary analysis of EMG variance as an index of change in EMG biofeedback treatment of tension-type headache

The effectiveness of EMG biofeedback training for tension headache has been well established. Previous studies evaluating changes in an average EMG activity score from pre- to posttreatment have not consistently found a relationship between a reduction in average EMG activity and headache improvement at posttreatment. The current study is a preliminary analysis of the utility of EMG variance as another possible mechanism of change. Frontalis EMG average activity and variances from 6 chronic tension-type headache sufferers who demonstrated significant improvement in headache activity at posttreatment (at least 70%) and 6 chronic tension-type headache sufferers who did not demonstrate improvement (less than 30%) were examined across 6 sessions of biofeedback treatment. The improved group demonstrated larger time-specific EMG variance in relation to mean EMG amplitudes during all treatment sessions. A dramatic decline in time-specific variance was observed during the later treatment sessions for improved participants; this pattern was not observed in the group who demonstrated little or no improvement. Results from the current study suggest that the inclusion of both average EMG activity and EMG variance may provide a more comprehensive measure to evaluate possible physiological changes responsible for improvement in headache activity following EMG biofeedback training.     

Biofeedback,relaxation training,and music: Homeostasis for coping with stress

This study compared the efficacy of five relaxation training procedures, four of which employed EMG auditory feedback: (1) biofeedback only (BF), (2) autogenic training phrases (ATP), (3) music (MU), (4) autogenic training phrases and music (ATP & MU), and (5) a control group, in developing self-regulation of a cultivated low arousal state as a countermeasure to tensed muscular reaction to stressful imagery. Twenty subjects established a pre- and posttraining frontalis region EMG biofeedback baseline measurement. Sixteen subjects were assigned at random to the 25-minute taped relaxation training procedure. After eight training sessions (4 weeks), MU and ATP & MU groups achieved highly significant differences when compared with the control group. The ATP & MU group attained the lowest postbaseline arousal level measured by the EMG. EMG as a physiological measure for transfer of training functioned well in detecting the psychophysiological affect of stressful imagery.This report is based on a thesis submitted in partial fulfillment of the requirements for the Master of Arts in Psychology degree by the author. The author extends his gratitude to Dr. Theodore Steiner, Dr. Paul Eskildsen, and Dr. Frank Hovell, who served on the committee, and to Rosemary Kolentus, for her help with this article.     

Skin temperature biofeedback for Raynaud's disease: A double-blind study

The lack of control procedures inherent in most of the experiments conducted to assess the effectiveness of skin temperature biofeedback in the treatment of Raynaud's disease renders the results inconclusive. In this study, control groups and a double-blind approach are adopted. Thirty-six patients, carefully screened for a diagnosis of primary Raynaud's disease, were assigned to a skin temperature increase group (N=12), to an EMG relaxation control group (N=12), or to a notreatment control group (N=12). All patients kept records of their symptoms for the duration of the study. Each subject in the two training groups received 20 sessions, the last 2 conducted under cold stress. Data analysis according to original group assignment, as well as following regrouping of subjects according to several learning criteria, showed that while all patients reported a marked decrease in the number of vasospastic attacks, no significant differences were found among the three groups on the clinical measures used to assess symptomatic relief. The general improvement reported must therefore be attributed to nonspecific factors.This study was supported in part by Rehabilitation Services Administration Grant No. 16-P-56810/5–17 to the University of Minnesota Medical Rehabilitation Research and Training Center. We are grateful to Gail Gaebe, Carla Grossman, Steve Janousek, Linda Rubbelke, and Scott Williamson, who served as blind assistants, and to Steve Sheffield for his technical support.     

The Effect of Biofeedback on Function in Patients with Heart Failure

Decreased HRV has been consistently associated with increased cardiac mortality and morbidity in HF patients. The aim of this study is to determine if a 6-week course of heart rate variability (HRV) biofeedback and breathing retraining could increase exercise tolerance, HRV, and quality of life in patients with New York Heart Association Class I-III heart failure (HF). Participants (N = 29) were randomly assigned to either the treatment group consisting of six sessions of breathing retraining, HRV biofeedback and daily practice, or the comparison group consisting of six sessions of quasi-false alpha-theta biofeedback and daily practice. Exercise tolerance, measured by the 6-min walk test (6MWT), HRV, measured by the standard deviation of normal of normal beats (SDNN), and quality of life, measured by the Minnesota Living with Congestive Heart Failure Questionnaire, were measured baseline (week 0), post (week 6), and follow-up (week 18). Cardiorespiratory biofeedback significantly increased exercise tolerance (p = .05) for the treatment group in the high (≥31%) left ventricular ejection fraction (LVEF) category between baseline and follow-up. Neither a significant difference in SDNN (p = .09) nor quality of life (p = .08), was found between baseline and follow-up. A combination of HRV biofeedback and breathing retraining may improve exercise tolerance in patients with HF with an LVEF of 31% or higher. Because exercise tolerance is considered a strong prognostic indicator, cardiorespiratory biofeedback has the potential to improve cardiac mortality and morbidity in HF patients.

Comparison of Biofeedback and Relaxation in the Treatment of Pediatric Headache and the Influence of Parent Involvement on Outcome

The relative efficacy of EMG-frontalis feedback and progressive relaxation was examined in children with tension-type or combined headaches (8–14 yrs. old). Furthermore, the influence of parent involvement, in the form of a three-session educational approach, on training outcome was systematically explored (2 × 2 factor design). Fifty children took part in the study, 40 were randomly assigned to the four different treatment conditions, 10 children participated in the self-monitoring control group. The training comprised 6 sessions of 1 hr each in the relaxation treatment and 12 sessions of 1/2 hr duration in the biofeedback group. Headache diaries were kept by children and parents for 4-week period prior to therapy, and for a similar length of time at post-treatment and follow-up (6 months). Multivariate analyses of variance on the headache diary data yield no significant main or interaction effects of treatment format or of parent involvement, but only a main effect of period, indicating a general efficacy of the four treatment conditions. At follow-up the reduction of headache activity is even more prominent. A different evaluative approach points to the superiority of biofeedback revealing a mean effect size for biofeedback training that reflects a good to excellent improvement rate. Correlations between headache data from children and parents are high.     

Electromyographic biofeedback treatment of a woman with chronic dysphagia

In this case report, a 25-year-old female with chronic dysphagia spastica(difficulty swallowing because of constriction of the throat muscles) was treated with 20 sessions of frontal electromyographic(EMG) biofeedback and home-relaxation practice. The subject monitored on a 10-point scale her difficulty swallowing during meals for 2 months prior to treatment, during treatment, and after treatment. There was a significant decrease in reported difficulty swallowing associated with frontalis EMG feedback. Improvement was maintained at a 6-month follow-up.