Effects of frontalis tension level on discrimination task accuracy and reaction time.

The frontalis muscle is a focal point of many relaxation training programmes, so the effects of varying frontalis tension levels on concurrent task performance need consideration when recommending in situ muscle relaxation. Two experiments are reported; performance on a discrimination task was examined across high, moderate, and low induced frontalis tension. When length of exposure to the task stimuli was unlimited, accuracy of discrimination was affected by tension; when exposure was limited, reaction time was affected. In both experiments the high frontalis tension resulted in better performance than the other levels. Implications for the practice of in situ relaxation are considered.

Respiratory resistance feedback in the treatment of bronchial asthma in adults.

Two studies evaluated feedback of total respiratory resistance of the airways (TRR) as a treatment for adults with moderate to severe chronic bronchial asthma. Respiratory function tests and questionnaires were used to select the patients and to assess treatment effects. Study I provided eight biofeedback sessions in four weeks (each session containing four, 3-min training trials) plus three pre-treatment and three post-treatment sessions. Over the eight treatment sessions biofeedback failed to produce any significant improvements, although overall the nine patients showed lower mean initial TRR values at the three post-treatment sessions compared with the three pre-treatment sessions. Patients consistently showed improvement following bronchodilator administration at the end of every session. In study II, biofeedback was provided in one intensive session of 20, 2-min trials. While careful instruction about biofeedback was provided to subjects, and more post-treatment measures were included, no significant improvements were shown following biofeedback, but were shown following bronchodilator administration.

Effects of pelvic muscle tension and expectancy on general and specific indicators of sexual arousal.

One group of 20 males was told that tensing the pelvic musculature would enhance sexual responsiveness (tension-good), while another group of 20 males was told that relaxation would increase responsiveness (relaxation-good). Using feedback to regulate EMG to predetermined levels, subjects were required in a counterbalanced design to tense and relax while viewing one of two matched series of 14 erotic slides interspersed with neutral slides. Expectancy and induced tension or relaxation both affected penile response: Relaxation was accompanied by lower levels of penile volume response to slides than was tension but only in the relaxation-good group. A similar pattern of means was shown in scores on a general arousal factor with virtually equal contributions from respiration rate, respiration amplitude, and heart rate. These data are interpreted to show that tension enhanced responsiveness irrespective of induced expectancy but that the effect of relaxation depended upon whether subjects were (correctly) informed that tension was conducive to greater response. Over subjects and conditions, penile volume was poorly correlated with the other physiological measures.

The effects of induced frontalis tension variation on aspects of cognitive efficiency.

Sixteen subjects performed a serial reaction-time task while varying frontalis tension levels. There were three levels of induced tension variation: high, moderate and low. Results indicated that reaction times were differentially affected across the three tension levels, and the slow response end of the reaction-time distribution was slightly more sensitive to frontalis tension changes than the median. The relative importance of errors of omission and errors of commission may determine which tension level is optimal for task performance, but the results reported here indicate that attempts to reduce frontalis tension levels may be inappropriate in situations requiring sustained alertness.

The role of awareness in the control of frontalis muscle activity.

An experiment was conducted to evaluate whether awareness of change in frontalis muscle activity was necessary and sufficient for voluntary control over the muscle. Forty subjects were required to relax, tense and complete both a test of awareness and an isometric magnitude production task, using the frontalis muscle. Following the completion of these pre-training assessment procedures, one group of subjects underwent either: Training in muscular awareness; biofeedback training in muscular control; both awareness and muscular control training; or a non-training control procedure. Following training, all subjects were again evaluated using the pre-training assessment procedures. The results indicated that an increase in awareness was not sufficient to produce an increase in muscular control, nor was it necessary for an increase in the ability to tense the frontalis muscle. These results suggest that Brener's model of voluntary control needs to be re-examined.

Reduction of stuttering by young male stutterers using EMG feedback.

A clinical program was designed in which male stutterers (age 10-14 years) were trained to reduce speech muscle tension by application of electromyograph (EMG) feedback. The program was designed (a) to reduce nonspeech EMG activity of facial muscles involved in speech, (b) to use this skill for control of muscle EMG activity while speaking, (c) to maintain the physiological EMG activity reduction with behavioral self-control techniques. Three subjects were treated on a single-subject ABCD baseline design, with an ABABAB reversal design within the treatment (B) phase. EMG feedback was shown to reduce stuttering in the clinic. After maintenance techniques were taught, stuttering was shown to have reduced 60-80% in the home environment while speech rate remained constant or increased. A 9-month follow-up showed that the improvement produced in treatment was continuing.