Effect of trainer's presence and response-contingent feedback in biofeedback-relaxation training

The present study investigated the effects of a trainer's presence vs a trainer's absence on subject-controlled, response-contingent relaxation training. Ten college students each received either frontalis EMG biofeedback training with trainer present, biofeedback training with trainer absent or information/placebo control with a trainer present. The relaxation procedure included a .5-hr baseline session and five .5-hr. training sessions. Analysis indicated that the biofeedback groups showed greater within-session reduction of EMG activity than the control condition but did not differ from each other. Post-session EMG levels across training sessions showed a significant decrease for all three groups. However, the two biofeedback groups relaxed more across sessions than did the control group and the two biofeedback groups did not differ from each other. Subjective ratings showed that subjects in all conditions became more relaxed both within and across sessions. The results indicate that a trainer's presence is not crucial in facilitating subject-controlled, response-contingent relaxation training.