Publication Date


Document Type


First Advisor

Martin, Randall B.

Degree Name

M.A. (Master of Arts)

Legacy Department

Department of Psychology


Heart beat; Biological control systems


This research project sought to extend previous finding relating personality characteristics to autonomic control. Specifically, past research has shown people who differ on the dimension of locus of control display varying degrees of control of their cardiac activity. Subjects who score as in ternals on this dimension have been found to be better at cardiac acceleration than are those subjects who score as externals. Studies which have examined the relationship between cardiac deceleration and locus of control have yielded inconsistent results. A second focus of the present study concerns the effectiveness of providing subjects specific strategies with which to control their heart rate. Several studies which have examined the effects of instructions such as these have yielded conflicting results. Since externals have been found to rely more on cues from the environment than do internals, it was reasoned that externals may derive greater benefit from the strategy instructions. That is, since internals are more prone to rely on their own resources, their performance on a task of autonomic control should not differ when they are given instructions. Externals, on the other hand, may derive considerable benefit from them. It was predicted that these differences would be more apparent during cardiac acceleration than deceleration. A group of 150 male introductory psychology students completed the Rotter IE Scale, a measure of locus of control. The subjects whose scores were extreme in either direction were invited to participate in the second phase of the study. There were 30 internals and 30 externals who participated in the second phase of the study. Half of the subjects in each of these groups were provided specific strategy instructions. Subjects were asked to try to raise and lower their heart rates during 20 60- second trials. The raise and lower trials were randomly ordered. Subjects were provided with analogue feedback of their heart rate. Heart and respiration rates were monitored for all subjects. Results indicated that all groups displayed equal skill at cardiac slowing. The mean for the group of internals with instructions exceeded those for the other three groups during the raise condition however. Subsequent analyses revealed that subjects in the internal instruction group had accelerated rates of respiration which coincided with the cardiac increases. When respiration rates were controlled statistically, the group differences became less apparent. It was concluded that the performance of subjects in the present study was largely due to the constraints imposed by the methodology employed. It was proposed that the present methodology offered a greater challenge than did those of previous studies. Suggestions for future studies underscored the importance of consistent methodology in studies in this area.


Includes bibliographical references.||Includes illustrations.


79 pages




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