Variations in digital temperature during frontal EMG biofeedback training in normal subjects

During frontal EMG biofeedback training, the relationship between frontal EMG and digital skin temperature was investigated in two experiments, which varied the number of baseline and feedback sessions. The results of Experiment 1 suggested a general relaxation effect, where digital temperature increased as frontal EMG decreased, especially for subjects with initially low hand temperature. Experiment 2 extended the number of baseline and feedback sessions and qualified the results of Experiment 1. EMG and digital temperature did not simultaneously converge toward general relaxation over the extended baseline or feedback sessions in Experiment 2. Furthermore, when the feedback signal was introduced, digital temperature dropped quickly but recovered to baseline levels within three feedback sessions; this drop in digital temperature was interpreted within the context of attentional demands of the biofeedback task. The results appeared consistent with the view that frontal biofeedback training teaches a discriminative skill of lower frontal EMG, and that this skill does not readily generalize to digital skin temperature.This research was supported by Grant 2 S06RR08038-17 funded by the National Institutes of Mental Health.     

Plasma catecholamine levels during temperature biofeedback training in normal subjects

Thirty-nine normal volunteers of both sexes were randomly assigned to receive 8 sessions of temperature biofeedback or autogenic training to increase finger temperature. Temperature biofeedback subjects produced significant elevations in finger temperature during training, whereas those who received autogenic training did not. Temperature feedback subjects had significantly higher heart rates and diastolic blood pressures during training compared to autogenic subjects. There were no significant changes or group differences in plasma catecholamine levels. These data do not support the hypothesis that feedback-induced vasodilation is accompanied by decreased sympathetic activation in normal populations, when only temperature biofeedback is employed.Supported by research grant No. HL-30604 from NHLBI. Dr. Angela McGuady served as Action Editor for this paper.     

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 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.     

Generalization of EMG biofeedback training

Five young adults received audio biofeedback training to reduce trapezius EMG levels while they engaged in reading in an office, seated at a table. A multiple-baseline-across subjects design was employed in two separate studies. After training, all subjects demonstrated reduced EMG levels while reading in a home or library setting. The first study suggested that subjects reduced EMG levels by minimizing movements and altering their postures; the second study systematically demonstrated changes in such behavior, which was correlated with EMG levels. The data provide evidence that EMG biofeedback resulted in response generalization across several motoric classes, and in stimulus generalization from the training setting to the natural environment. The importance of assessing generalization is discussed.     

Generalization of EMG biofeedback training

Five young adults received audio biofeedback training to reduce trapezius EMG levels while they engaged in reading in an office, seated at a table. A multiple-baseline-across subjects design was employed in two separate studies. After training, all subjects demonstrated reduced EMG levels while reading in a home or library setting. The first study suggested that subjects reduced EMG levels by minimizing movements and altering their postures; the second study systematically demonstrated changes in such behavior, which was correlated with EMG levels. The data provide evidence that EMG biofeedback resulted in response generalization across several motoric classes, and in stimulus generalization from the training setting to the natural environment. The importance of assessing generalization is discussed.     

A comparison of frontal EMG biofeedback and neck EMG biofeedback in the treatment of muscle-contraction headache

EMG biofeedback from the frontal area (FFB) was compared to EMG biofeedback from the neck (NFB) in the treatment of chronic muscle-contraction headache. Both treatment groups (N=10) evidenced significant decreases in reported headache activity, with the NFB group also significantly reducing medication consumption. An analysis of EMG changes suggested that subjects were able to produce large within-session changes in EMG activity during initial sessions, with the major effect of additional training being an increase in speed with which these changes occurred. In neither group, however, did changes in EMG activity correspond closely to changes in reported headache 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.     

Generalization of lowered EMG levels during musical performance following biofeedback training

Electromyographic (EMG) biofeedback training offers a means by which musicians can control excess muscle tension during performance. Music instructors generally agree that unnecessary muscle tension not only leads to physical problems but also can interfere with performance quality. It is important, however, that the reduced EMG levels resulting from biofeedback training generalize to situations in which feedback is not available, and that the reduction in muscle tension not result in decreased performance quality. Eight intermediate to advanced clarinet players participated in four EMG biofeedback training sessions during which short-term and extended generalization of lowered EMG levels was assessed along with trill and scale speed scores. Significant reductions in EMG levels associated with biofeedback training generalized to short-term and extended situations, while trill and scale performances remained at or above pretest levels.     

The effectiveness of EMG biofeedback training in low back pain

Eighteen patients with chronic low back pain(lbp) of muscle tension origin were given an EMG biofeedback training. Compared to seven controls they showed a significant decrease during training in muscle tension and subsequently in pain. However, at follow-up EMG levels dropped to the initial(high) level. Pain scores of patients with high pain decrements during training showed further improvement during follow-up, which was not the case with patients showing less substantial improvement. The importance of cognitions was discussed.We wish to express our thanks to Marijke Höweler-van Dalen for supervising this investigation, to Arnold Goedhart for statistical advice, to Dr. Orlebeke for his critical remarks, and to Dr. Penders for referring the patients in Amsterdam. We are particularly indebted to the general practitioners Paul Kreutzer and Jan Huls for referring the Andijk patients. Without their support this investigation would not have been possible.     

Flexibility development in sprinters using EMG biofeedback and relaxation training

This study compared the effectiveness of electromyographic (EMG) biofeedback and relaxation treatment in producing flexibility increases at the hip joint. Retention of flexibility gains and changes in sprinting performance were also examined. Fifteen male and 15 female athletes, predominantly sprinters, were matched according to age, sex, and flexibility and were randomly assigned to one of three groups. The control group received only the testing, the biofeedback group received visual and auditory EMG training, and the relaxation group received modified PMR and imagery exercises. Subjects in the two experimental groups were given eight twice-weekly 10-minute sessions and then were retested for flexibility. Retention of flexibility was reassessed 2 and 4 weeks later. Sprint performance improved for all groups. EMG biofeedback and relaxation treatment methods were no more effective than stretching exercises used by the control group for improving flexibility during the treatment period, but they did produce evidence of superior flexibility gains in the retention period. This may be important as flexibility has been reported to be related to the incidence of injuries.     

The effectiveness of EMG biofeedback training in low back pain.

Eighteen patients with chronic low back pain (lbp) of muscle tension origin were given an EMG biofeedback training. Compared to seven controls they showed a significant decrease during training in muscle tension and subsequently in pain. However, at follow-up EMG levels dropped to the initial (high) level. Pain scores of patients with high pain decrements during training showed further improvement during follow-up, which was not the case with patients showing less substantial improvement. The importance of cognitions was discussed.     

Parasympathetic rebound following EMG biofeedback training: A case study

The self-regulation literature contains very few reports of negative side-effects stemming from biofeedback training. Nevertheless, the case reported here is unique in that immediately following each of several early EMG feedback sessions, an otherwise headache-free patient reported an acute attack of headache and nausea. These attacks, the conditions under which they appeared, and the conditions leading to their remission will be described. Discussion will focus on the possible physiological mechanisms involved.     

Parasympathetic rebound following EMG biofeedback training: a case study

The self-regulation literature contains very few reports of negative side-effects stemming from biofeedback training. Nevertheless, the case reported here is unique in that immediately following each of several early EMG feedback sessions, an otherwise headache-free patient reported an acute attack of headache and nausea. These attacks, the conditions under which they appeared, and the conditions leading to their remission will be described. Discussion will focus on the possible physiological mechanisms involved.     

Predictors of success in the EMG biofeedback training of hyperactive male children

EMG biofeedback training is continuing to evolve as a promising treatment of hyperactivity. But while research on its application suggests that this technique induces significantly lower EMG levels in experimental samples as a whole, it also discloses that some children evidence but limited reductions. Most likely, this variability is introduced by differences in subject attributes. This study assessed that prospect by examining whether four common subject characteristics correlated with the extent of decrease in EMG level achieved by 59 hyperactive school-aged boys. Those variables were pretreatment EMG level, age degree of hyperactivity, and locus of control. Number of applications or training sessions was included as the fifth predictor. A multiple regression analysis determined that only locus of control was predictive of success in EMG training; however, it accounted for 72% of the variance Implications of these findings are discussed.     

Effectiveness of EMG biofeedback training for controlling arousal in subsequent stressful situations

Thirty-five subjects participated in (1) a pretreatment session during which arousal was measured while subjects anticipated and then viewed a stressful film; (2) four 20-min treatment sessions during which subjects received either contingent EMG biofeedback (biofeedback treatment), instructions to attend to a variable pitch tone (attention-placebo control), instructions to relax as much as possible (instructions-only control), or instructions to sit quietly (no-treatment control); and (3) a posttreatment session that was identical to the pretreatment session. Results indicate that when compared to the subjects in the control conditions, subjects who received EMG biofeedback were not effective in reducing frontalis EMG levels during treatment or while viewing the stressful film, but they were effective in reducing frontalis EMG levels while anticipating the stressful film. There was no evidence that EMG biofeedback influenced either skin conductance or self-reports of arousal.This research was supported in part by Bio-Medical and General Research Fund grants from the University of Kansas to David S. Holmes. Appreciation is due to B. Kent Houston, Edward F. Morrow, and Charles A. Hallenbeck for their contributions to the project.     

Cognitive skills training versus EMG biofeedback in the treatment of tension headaches

In an effort to study the role of cognitive skills training in the treatment of psychosomatic disorders, two single-case design experiments were conducted to assess the relative effectiveness of biofeedback procedures and cognitive coping techniques in the alleviation of tension headaches. For both subjects, biofeedback training influenced mean frontalis EMG levels, although such changes were not associated with concomitant reductions in headache activity. It was the presence or absence of cognitive skills training, however, that determined whether each subject reported changes in headache levels. These results suggest that a more efficient treatment approach for tension headaches would involve an increased emphasis on the modification of maladaptive cognitive activity. The present findings support the general view that a comprehensive approach in the treatment of stress-related disorders requires a concomitant focus on the cognitive, behavioral, and affective dimensions of the symptom. It was also suggested that biofeedback technology may be a useful tool for studying the physiological consequences of particular cognitive processes and in identifying particular cognitions with anxiety-provoking properties.     

Predictors of success in the EMG biofeedback training of hyperactive male children

EMG biofeedback training is continuing to evolve as a promising treatment of hyperactivity. But while research on its application suggests that this technique induces significantly lower EMG levels in experimental samples as a whole, it also discloses that some children evidence but limited reductions. Most likely, this variability is introduced by differences in subject attributes. This study assessed that prospect by examining whether four common subject characteristics correlated with the extent of decrease in EMG level achieved by 59 hyperactive school-aged boys. Those variables were pretreatment EMG level, age degree of hyperactivity, and locus of control. Number of applications or training sessions was included as the fifth predictor. A multiple regression analysis determined that only locus of control was predictive of success in EMG training; however, it accounted for 72% of the variance. Implications of these findings are discussed.     

A simple EMG—Reward system for biofeedback training of children

An automated reward system to be used with standard electromyographic (EMG) biofeedback instrumentation is described. The on-line reward system, when coupled with standard biofeedback instrumentation and procedures, constitutes instrumental conditioning. In addition to describing the EMG—reward interface circuity, a study demonstrating the efficacy of the instrumental conditioning approach with cerebral-palsied children is presented.This research was aided by a grant from the Easter Seal Research Foundation of the National Easter Seal Society for Crippled Children and Adults, and by a grant from the Tulsa Cerebral Palsy Association.     

The response of manual motor functioning in Parkinsonians to frontal EMG biofeedback and progressive relaxation

The purpose of the current investigation was to determine the effects of frontal EMG biofeedback and progressive relaxation training on manual motor functioning in Parkinsonians. Twenty patients were matched and randomly assigned to two groups. All subjects were administered a brief manual motor assessment. The experimental group then underwent weekly sessions of frontal EMG and relaxation training for a period of 15 weeks. At the conclusion of the training period, both experimental and control groups were again administered the manual motor tasks. The results indicated that Parkinsonian patients are capable of significantly lowering frontal EMG activity levels. The motor task results, however, yielded no statistically significant differences between the two groups as a result of the biofeedback training.