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J Segreto-Bures

Publications and source records attributed to J Segreto-Bures.

3 recordsLinked to original sources
PubMed1984

Effects of noncontingent feedback on EMG training, EMG responses, and subjective experience.

Various types of noncontingent feedback have been used as control procedures in EMG training; however, their effects on such training have received little attention. Experiment 1 in the present study examined the effects of noncontingent feedback on EMG training, and Experiment 2 assessed the effects of feedback characteristics on EMG responses. In Experiment 1, three noncontingent feedback groups (yoked control, randomly fluctuating tones, and decreasing tones) and one contingent group underwent 20 minutes of training for frontal EMG decreases. Procedures in Experiment 2 were identical to those in Experiment 1 except that subjects were instructed merely to listen to the feedback tones. Results of Experiment 1 indicated that contingent and noncontingent fluctuating feedback groups achieved significantly lower EMG levels than noncontingent decreasing and yoked control groups. In Experiment 2, however, no differences in EMG activity were found among groups. In both experiments, groups did not differ in terms of subjective variables such as frustration, suspiciousness about the tone, or length of time attending to the tone. Results of these two experiments suggest that differences in EMG responses to various types of noncontingent feedback result from interactions between characteristics of the feedback stimulus and instructions to decrease the stimulus.

Adolescent↗
PubMedDate not supplied

Subject expectancy effects in frontal EMG conditioning.

The influence of subject expectancies on performance has been examined extensively within the framework of behavior therapy but has received little attention within the context of EMG training. This study assessed the effects of subject expectancy on acquisition during frontal EMG conditioning. Prior to conditioning, subjects were either given no expectancy or instructed that learning to control the feedback stimulus would be either easy (high expectancy) or difficult (low expectancy). Subjects in the three expectancy conditions then underwent 20 min of contingent reinforcement for frontal EMG decreases. Three similar groups of no, low, or high expectancy subjects received noncontingent reinforcement. Differential EMG behavior was exhibited between the two no-expectancy groups, with the contingent group reliably lower in EMG activity than that noncontingent. However, differences were not observed between contingent and noncontingent subjects given either low or high expectancy sets. None of the groups could be differentiated on the basis of subjective variables such as anxiety, relaxation, or frustration. These findings suggest that subject expectancies, either positive or negative, interfere with the acquisition of conditioned EMG behavior.

Adolescent↗