Date of Award


Degree Type

Thesis - Restricted

Degree Name

Master of Arts (MA)




Twenty-three undergraduate college students participated in four weekly frontalis EMG biofeedback sessions . Subjects were initially divided into internals and externals by the Health Locus of Control scale, and assigned to a biofeedback or control condition. Training was followed by a post-test with the Health Locus of Control scale . It was predicted that internals would achieve greater EMG decreases than externals . It was also hypothesized that biofeedback externals would achieve great er pretest to post-test (internally directed) changes in health locus of control scores than the control externals . Pretest to post-test EMG levels were obtained for each of the four sessions for both the biofeedback and control conditions. Some support for the fir s t hypothesis was indicated by a significant interaction between condition and health locus of control group , based on EMG change scores (pretest session one minus post-test session four) . Results of a Scheffe test on mean pairs indicated significant differences between biofeedback internals and control internals , and biofeedback internals and control externals . Thus , among the internals , those in the biofeedback condition achieved greater EMG decreases than those in the control condition , and under the biofeedback condition , internals exhibited greater EMG decreases than externals . A nonparametric sign test on the health locus of control regressed change scores was nonsignificant , failing to support the second hypothesis .