Effect of EMG Biofeedback and Progressive Muscle Relaxation Training on Awareness of Frontalis Muscle Tension

Awareness of muscle tension, as estimated by a modification of the Kinsman et al. (1975) procedure for determining probability of correct estimation (P(c)) of absolute differences in muscle tension between adjacent trials, was examined before and after volunteer subjects underwent 4 sessions of either: 1) EMG biofeedback (BF) training, 2) progressive muscle relaxation (PMR) training, or 3) a placebo-control (MC) procedure which involved listening to music as an alleged guide for relaxation. The subjects were 30 females (mean age = 28.3 yrs) responding to an offering of experimental treatment for anxiety and tension. Measurements of frontalis muscle tension (EMG) and P(c) were made before and after training. The results showed that EMG was significantly reduced by BF and PMR training but not by the MC procedure. Increases in P(c) after training were significantly greater for BF than for PMR or MC training. There were no group differences for subjective report of tension. Correlations between pre- to post-training EMG and P(c) change scores were significant only for the BF group and the combined group of BF and PMR subjects. These results suggest that: 1) both BF and PMR training were effective in producing frontalis EMG reductions, 2) the following relationship may exist among training groups in terms of relative influence upon awareness of tension—BF training > PMR training > MC training, and 3) awareness of tension appears to be related to the ability to reduce EMG although the exact nature of this relationship remains unclear.     

Striate Muscle Tensional Patterning in Frontalis EMG Biofeedback

Four normal male subjects were exposed to 5 30-min alternate-day sessions of continuous frontalis EMG biofeedback training preceded by 15-min adaptation periods. A computer-controlled scanning electromyograph sampled integrated EMG activity from the frontalis and seven adjunctive muscle groups. Tensional profiles for all eight muscle groups were assembled every 1.84 sec, resulting in an 8 × 960 data array for each session. Statistical analyses revealed that although frontalis EMG levels decreased significantly in the training, those of adjunctive recording sites did not. Cross correlation analyses for session 1 frontalis and adjunctive site EMG levels showed typically negligible correlations at all temporal lags, although some neck sites showed moderate cross correlation with the frontalis in 2 subjects. Separate principal-component analyses for sessions 1 and 5 produced little evidence for a general muscle tension factor. Low coefficients of congruence between session 1 and session 5 truncated-component solutions demonstrated little replicability of tensional linkages from the first to the last session.     

Intersession Interval and Reductions in Frontalis EMG During Biofeedback Training

Subjects were given practice in reducing frontalis EMG using biofeedback procedures with either Short, Medium, or Long intervals between practice sessions. After 10 sessions there were significant differences among the groups in decreasing EMG amplitude.     

Lack of Correlation Between Frontalis EMG and Either Neck EMG or Verbal Ratings of Tension

Eight normal subjects were trained with the aid of EMG feedback to successively increase and decrease the activity of the frontalis muscle on 5 consecutive days. Along with the activity of the frontalis, sternomastoid EMG was recorded from 4 subjects and EMG from both the semispinalis and splenius capitus was recorded from the other 4 subjects. Estimates of the degree of subjective tension or relaxation were obtained following Baseline, Increase Frontalis, and Decrease Frontalis periods on each treatment day. Frontalis EMG activity showed significant increases and decreases relative to baseline levels during appropriate periods. Sternomastoid EMG did not change significantly during either Increase Frontalis or Decrease Frontalis periods. Semispinalis/splenius EMG activity also did not change during Increase Frontalis periods, but increased significantly during Decrease Frontalis periods. Subjects’estimates of subjective tension increased above baseline during increases in frontalis EMG activity, but did not change significantly during decreases in frontalis EMG. These data support the findings of Alexander that changes in frontalis EMG neither generalize to other somatic muscles nor correlate with verbal reports of cognitive tension or relaxation.     

Generalized Muscle Changes during EMG Relaxation Training

Tension levels from muscles in the forehead (frontalis) and back of the neck (semispinalis capitis) were simultaneously recorded during short term relaxation training with EMG feedback to assess the efficacy of this technique for producing generalized deep muscle relaxation. The degree of association between the activity of the two muscles was measured both with cross-correlation coefficients and a linear regression technique. The two muscles showed a tendency to covary which did not change during training and was unrelated to which muscle was the source of feedback. These results provide evidence for a moderate degree of association between these muscle groups during relaxation training and suggest that EMG feedback may be more useful in producing general relaxation than was previously thought.     

Relaxation Training and Biofeedback in the Reduction of Reducation Muscle Tension

To assess the comparative effectiveness of frontalis electromygraphic (E M G) biofeedback and relaxation instructions in reducing frontalis EMG levels, 101 male and female university students were randomly assigned to one of the following groups: 1) frontalis EMG biofeedback (variable frequency auditory feedback). 2) passive relaxation instruct inns (instructions to attend to and relax mustiest. 3) active relaxation instructions tensing and relaxing exercises), 4) false feedback, and 5l no treatment control. In a one-session design, subjects receiving biofeedback and passive relaxation instructions demonstrated the greatest decrement in frontalis EMG level. The relationships between decrements in frontalis EMG level and sex, baseline EMG and manifest anxiety are discussed.     

A Comparison of Auditory and Visual Feedback in Biofeedback Assisted Muscular Relaxation Training

This study compared the efficacy of auditory and visual feedback in electromyographic (EMG) biofeedback assisted relaxation training of the frontalis muscle.Twenty-eight subjects, divided into 4 groups matched on baseline frontalis EMG levels and trait anxiety, received 7 training sessions each under one of the following conditions: (1) auditory feedback-eyes closed; (2) auditory feedback-eyes open; (3) visual feedback; or (4) no feedback-eyes closed. The group who received auditory feedback with the eyes closed manifested significant lowering of EMG over session compared to no significant reduction in EMG for the other three groups. EMG changes failed to correlate significantly with changes in self reports of subjective relaxation derived from pre-to-post session state anxiety test data. The possibility that the ineffectiveness of visual feedback in this study may be specific to the frontalis muscle was discussed and the need for further research in several areas was stressed.     

Frontalis Muscle Tension and Sleep Latency

This study examined the relationship between frontalis muscle tension and sleep latency. Fifteen subjects reporting various sleep latencies participated. In addition to recording frontalis muscle tension, sleep was monitored on a polygraph for 3 nights. Contrary to expectation, the waking frontalis EMG level did not predict sleep latency. If future research were to show a similar lack of relationship between tension in other muscle groups and sleep onset, it would call into question the use of muscle relaxant drugs and muscle relaxation training in the treatment of sleep-onset insomnia.     

Training and Transfer of Training Effects in EMG Biofeedback Assisted Muscular Relaxation

Twenty-two normal adults participated in an electromyographic (EMG) biofeedback experiment designed to test if the feedback stimulus is necessary in obtaining EMG reductions during typical laboratory procedures, and if prior training on one muscle facilitates the training of a second muscle. One group of subjects received forearm feedback training followed by frontalis training. A second group received training in the reverse order. Two control groups relaxed first on their own followed by either forearm or frontalis training. Attention was directed toward motivating control subjects to perform maximally during relaxation without feedback. Heart and respiration rates and skin conductance and temperature were also recorded. Both trained and untrained subjects produced significant EMG reductions but did not differ from each other; nor did a transfer of training effect emerge. No differences resulted between feedback and non-feedback conditions for the other physiological measures or for changes in state anxiety. These data compromise somewhat the previous demonstrations of EMG biofeedback “learning,” and are unsupportive of EMG biofeedback as a general relaxation training technique.     

肌电反馈放松训练对大学生失眠症治疗作用的初步探索

目的: 探究肌电反馈放松训练对大学生失眠症的治疗作用.方法: 采用肌电反馈放松训练对36例失眠症患者进行治疗,在治疗前后让失眠症患者填写抑郁自评量表、焦虑自评量表,并记录治疗前后被试的睡眠多导图和肌电值.结果: 与治疗前相比,治疗后被试的睡眠潜伏期缩短(32.9 4±22.6/85.7 4±52.8,P=0.015),觉醒次数减少(1.8±0.8/3.5 4±1.5,P=0.031),快速眼动睡眠期时间延长(78.7 4±22.9/42.5±24.5,P=O.033),3期、4期睡眠时间延长(56.0 4±39.4/31.9 4±26.2,P±=0.024),睡眠效率提高(78.1 4±11.2/64.3 4±21.3,P=0.027);焦虑自评量表得分和抑郁自评量表得分均降低(30.9 4±5.3/35.7 4±5.8、40.9 ±8.6/43.7 4±6.2,P=0.027、0.016);肌电值降低(2.6 4±0.9/0.8±4±O.2,P=0.017).结论: 肌电反馈放松训练具有放松肌肉、缓解紧张、改善睡眠的作用.     

Simultaneous EMGs From Six Sites During Muscular Relaxation: A Comparison Between Forehead and Forearm Feedback

In light of the continuing popularity of frontalis EMG feedback for general relaxation purposes, a pertinent question is whether this procedure is superior to feedback from other muscles. This question was addressed by comparing a frontalis feedback group (n = 12) with a forearm feedback group (n = 10) in a one-session experiment. The experimental session included a 10-min rest period preceded by verbal relaxation instructions and demonstration of the respective feedback contingencies, and followed by a 30-min feedback period. EMG records were obtained from forehead, forearm, neck, masseter, sternomastoid, and lower leg. In the two target muscles, significant group differences developed during rest, but no additional significant effects were produced during feedback. Regarding the four untrained sites, EMG tended to decrease in the forehead group, but not significantly below the levels of the forearm group. Simultaneous EMG cross-correlations within 5-min intervals based on successive 1-sec averages showed significant covariation between muscles in the head and neck area; the source of this covariation was uncertain, however—electrical “crosstalk” and generalized muscular responding were two possibilities discussed.     

The Effects of Feedback Sensory Modality, Feedback Information Content, and Sex on Short-Term Biofeedback Training of Three Responses

In three factorial experiments, auditory vs visual vs tactile feedback, analog feedback vs analog feedback which was anchored, and sex, were varied to assess the effects of these variables on performance in short-term biofeedback training of heart rate reduction, hand temperature increase, and forehead muscle tension reduction. A total of 108 subjects served in the study. Moderate but reliable changes were found during the course of the training session for all three physiological responses. The ability to reduce heart rate in a single training session did not appear to be a function of any of the variables manipulated in this study, but rather could be attributed to adaptation. In both muscle tension and temperature training, however, there were significant interactions between sex and sensory modality of the feedback stimulus and, in the case of muscle tension training, between information content of the feedback signal and sex. The overall pattern of results indicated that performance during biofeedback training is a complicated function of sex and the type of signal used to provide feedback, and that this function is not constant across physiological response systems.     

Multiple Response Comparison of Parietal EEG and Frontalis EMG Biofeedback

In Study I parietal EEG and frontalis EMG were simultaneously recorded from 20 normal subjects while half of the subjects received 45 min of eyes-closed alpha EEG enhancement feedback and the other half received a similar amount of EMG suppression feedback. EMG feedback resulted in a significant reduction in frontalis EMG activity accompanied by a reliable increase in parietal alpha density, while EEG feedback produced only an increase in alpha without corresponding EMG reduction. In Study II, each of 8 subjects underwent four separate feedback contingencies in two 40-min sessions—one session with eyes open and the other with eyes closed. The four types of feedback were: a) alpha-up (alpha enhancement), b) alpha-down (alpha suppression), c) EMG-down (frontalis tension decrease), and d) EMG-up (frontalis tension increase). EMG feedback, up and down, resulted in the more consistent pattern of generalized arousal changes reflected in heart rate and respiratory rate as well as EEG and EMG activity. Within the constraints of a limited training period, the results suggest that frontalis EMG feedback is the more efficient procedure for producing a generalized relaxation response. However, since fingertip vasoconstriction accompanied all four types of feedback, caution must be exercised to avoid the oversimplification of generalized organism effects.     

Placebo Effects in Biofeedback and Self-Perception of Muscle Tension

This study evaluated the effectiveness of laryngeal muscle biofeedback, a common treatment for subvocalization, utilizing a strict control group structure. Subjects were 29 undergraduates assigned to Laryngeal Feedback (N = 10), Masseter Feedback (N = 10), or No Feedback Control (N = 9) conditions. The results indicated that laryngeal muscle biofeedback had no specific treatment effect; however, masseter biofeedback demonstrated a specific treatment effect when the new procedure was utilized. Subjects in the Masseter Feedback Group displayed masseter EMG levels which were substantially lower than subjects in the Laryngeal Feedback Group (p<.05). In order to validate the results of the biofeedback control procedure, accuracy of myogenic perception was also tested, and found to be significant for the masseter (p<.001) but not for the laryngeal muscle. It is shown that the biofeedback control procedure can more accurately assess the presence or absence of specific treatment effects in biofeedback. Theoretical implications of the myogenic perception concept are discussed, and suggestions for future research in biofeedback and myogenic perception are provided.     

Biofeedback and Progressive Relaxation: Effects on Systolic and Diastolic Blood Pressure and Heart Rate

Two groups of subjects were pretrained in Jacobson's progressive relaxation, then instructed to lower their blood pressure while receiving contingent feedback or no feedback for two 1-hr sessions. A third group was pretrained in a control relaxation procedure, then instructed to lower blood pressure while receiving contingent feedback. All subjects returned for a Follow-up session in which they attempted to reduce blood pressure without feedback. The results indicated reliable decreases in systolic blood pressure for all three groups in the first two sessions. The group pretrained in progressive relaxation and given feedback achieved greater control than the other two groups which did not differ from each other. During the Follow-up session, blood pressure decreases were small but reliable in the two groups pretrained in progressive relaxation. Heart rate and diastolic blood pressure decreased in all groups, with the progressive relaxation groups achieving the lowest levels. It is concluded that progressive relaxation and blood pressure feedback in combination are highly compatible and that progressive relaxation allows for modest blood pressure control in the absence of feedback.     

Comparison of the Effectiveness of Biofeedback and Relaxation Training on Hand Warming

Finger pulse volume (FPV) biofeedback, relaxation training (RT), and finger temperature (FT) biofeedback were compared for their effectiveness in the alteration of hand temperature (HT). It was hypothesized that the use of FPV, a more direct measure of peripheral blood flow, should be more effective in producing hand warming than the demonstrably latent FT or the less direct RT manipulation. No significant difference in HT alteration was found between the two biofeedback training groups and neither the finger temperature nor finger pulse volume biofeedback groups were more successful than the relaxation training group in the alteration of HT. No significant differences were found in the alteration of FPV among the three groups. A major finding of this study indicates that all groups produced a significant inverted U training function across trials for both FT and FPV. In all cases, rapid learning was demonstrated in the early trials followed by a decline toward baseline in the later trials. These findings are discussed in terms of the role of strategy formation, frustration, saturation, and the limitations of the physiological learning process.     

帕罗西汀联合生物反馈治疗躯体形式障碍的疗效观察

目的比较帕罗西汀联合生物反馈放松疗法治疗躯体形式障碍的临床疗效。方法将50例躯体形式障碍患者随机分为研究组(帕罗西汀联合生物反馈放松疗法治疗)25例与对照组(单用帕罗西汀治疗)25例,于治疗前及治疗后第1、2、4周末用症状自评量表(SCL—90)躯体化因子分、汉密尔顿抑郁量表(HAM D)评定疗效。结果治疗后2组SCL—90躯体化因子分(t=2.38,P<0.01)、HAM D总分(t=2.35,P<0.01)较治疗前明显减少,差异有统计学意义。4周末有效率研究组80%,对照组52%,差异有统计学意义(P<0.01)。从第1周末开始,研究组SCL—90中躯体化因子分即明显低于对照组(t=2.51,P<0.05)。第2周末开始,研究组HAM D总分亦明显低于对照组(t=2.54,P<0.05)。结论帕罗西汀联合生物反馈比单用帕罗西汀治疗躯体形式障碍起效更快,疗效更佳。     

The Effect of Repeated Tense-Release Sequences on EMG and Self-Report of Muscle Tension: An Evaluation of Jacobsonian and Post-Jacobsonian Assumptions About Progressive Relaxation

This study tested three psychophysiological hypotheses generated from assumptions underlying post-Jacobsonian progressive relaxation techniques and assumptions that conflict with the rationale for Jacobson's progressive relaxation method. Twenty-eight subjects tensed and released tension from the forearm extensor and frontalis muscles during a series of trials interspersed with intervals of relaxation. Correlations between self-report of tension and EMG were moderate during relaxation, but did not increase across successive tense-release trials, thus indicating no increase in self-awareness of muscle tension. As predicted by Jacobson, paying attention to either muscle produced increased tension in the frontal area, but Jacobson's prediction of increases in forearm tension while paying attention to the forearm was not confirmed. Evidence was equivocal for the existence of the “pendulum effect” predicted by Bernstein and Borkovec. Tense-release trials produced gradual decreases in frontal EMG, but no changes in forearm EMG. Declines below baseline in self-reported muscle tension occurred only several minutes after the end of the tense-release trials, and did so for the forearm despite lack of EMG decreases in that area. This finding may reflect the influence of cognitive rather than muscular processes.     

Comparison of Frontal EMG Biofeedback and Several Types of Relaxation Instructions in Reducing Multiple Indices of Arousal

During the training phase, 96 subjects were given one of four types of relaxation instructions (single instructions, repeated instructions, relaxation training, no instructions) and in addition either did or did not receive frontal EMG biofeedback training. Results indicated that each of the instructions and biofeedback procedures were equally effective in reducing frontal EMG, but that none of these procedures had any effect on subjective anxiety or autonomic indices of arousal (pulse rate, skin temperature, and finger pulse volume). During the generalization/stress phase, subjects were threatened with electric shock and were told to apply the relaxation techniques they learned during the training phase even though no additional instructions and/ or biofeedback training would be provided. To assess the effectiveness of the shock manipulation, a no-threat control group was included. Results indicated that: a) the shock manipulation was effective in increasing arousal, b) previous instructions and/or biofeedback were equally effective in reducing frontal EMG levels, but that c) only relaxation training was consistently effective in reducing subjective and autonomic indices of arousal. These findings: a) suggest that in stressful situations, relaxation training may be more effective than either EMG biofeedback or simple relaxation instructions in producing a general relaxation effect as opposed to a specific EMG effect; and b) indicate the importance of assessing the effectiveness of relaxation procedures during stressful situations during which subjects’ levels of arousal are elevated above resting baseline levels.     

Myoelectric and Force Feedback in the Facilitation of Isometric Strength Training: A Controlled Comparison

Three groups of 10 normal subjects were trained with 13 maximal isometric contractions on each of 8 days. During 8 of the 13 trials, subject groups received either myoelectric feedback (MFB), or force feedback (FFB), or no feedback. Over the 8 training days all groups increased EMG activity, but no significant group differences in rate of acquisition were obtained. All groups made gains in force over the 8 days. Force feedback produced better acquisition than either MFB or control conditions. However, both MFB and FFB produced comparable and significant differences between feedback and no-feedback trials within a session, highlighting the importance of control group designs in the assessment of biofeedback effects. Dissociation between surface EMG and force was shown not only in the training effects, but also in the difference between feedback and no-feedback performance within a session. An analysis of covariance revealed that during feedback trials MFB produced some EMG facilitation which could not be attributed to increased force production. This effect may have been due to selective reinforcement by MFB of co-contraction in the extraneous musculature, or of changes in motor unit firing patterns. These phenomena may also account for the relative failure of MFB to facilitate force acquisition. A one-month follow-up showed significant retention following similar losses of force in all groups.