EMG Biofeedback with College Student Volunteers: Limitations of Effects of Independent Variables

Abstract

In the present study the relative effects of biofeedback, a set to relax, and a no set (adaptation) condition upon EMG changes in the frontalis muscles were addressed. Subjects were college student volunteers and the proportion of males to females was equal among groups. All subjects were first monitored for minutes (adaptation, no set). Subsequently, subjects in the biofeedback group were then instructed to relax and also to attend to feedback signals to facilitate relaxation for 20 additional minutes (1-min. trials). Subjects in the relaxation set group were given a set to relax but not biofeedback until the last 5-min. segment. Subjects in the no set group were given no instructions to relax and no biofeedback until the last 5-min. segment. Results indicated reductions of EMG monitored tension levels in all groups with no significant between-group differences. Pre- and poststate anxiety self-report measures also showed a significant reduction in anxiety for all groups but no between-group differences reached significance.