Biological Aspects of Self-Esteem and Stress

Abstract

The human stress response represents a basic mechanism to increase the availability of energy substrates in different parts of the body, and allow optimal adaptation to changing demands from the environment. However, psychological stress—and the emotions that tend to accompany threat perception such as anxiety and fear—can also interfere with performance and the effective self-regulation of behavior. In this chapter, we consider how specific personality variables, especially self-esteem and locus of control, play a central role in the appraisal of many situations, and thus contribute to the experience of stress. The studies described here provide evidence that participants with low self-esteem and low locus of control tend to show increased and more consistent release of cortisol in response to standardized laboratory stress tests. This effect is observable during stressful experiences, as well as in the failure of the cortisol response to habituate to repeated stress exposure. We further show how this endocrinology/personality link is systematically associated with hippocampal volumes, which are an important structure in the formation of memory, emotional regulation, and the regulation of the stress response. We suggest that stress dysregulation at the psychological level is due, at least in part, to impairments in memory associated with reduced hippocampal function. Taken together, this chapter highlights the importance of considering individual differences in self-esteem and locus of control in understanding people’s behavioral and endocrinological responses to stress.

Conclusions

A person’s response to stress is known to be linked to a number of psychological variables. A case can be made that specific personality variables, especially self-esteem and locus of control , play a central role in the appraisal of many situations, and thus contribute to the experience of stress. The studies described here provide evidence that participants with low self-esteem and low locus of control tend to show increased and more consistent release of cortisol in response to standardized laboratory stress tests. This effect is observable during stressful experiences, as well as in the failure of the cortisol response to habituate to repeated stress exposure.

We have further shown how this endocrinology/personality link is systematically associated with hippocampal volumes. The hippocampus is an important structure in the formation of memory, emotional regulation, and the regulation of the stress response. Variations in hippocampal volume have been postulated and shown to be systematically linked to HPA axis dysregulation, but intriguingly, the direction of this dysregulation is inconsistent across studies. We conclude that the dysregulation at the psychological level is due, at least in part, to impairments in memory associated with reduced hippocampal function: If specific situational and environmental characteristics associated with negative past events cannot be recalled, this lack of awareness of situational circumstance can lead to an overgeneralization of negative past events, and therefore an increased likelihood to consider the current situations as stressful as well. Thus, poor contextualization mediated by the hippocampus could be linked to abnormal stress responses on the one hand, and lower self-esteem on the other.

Taken together, the research that we have reviewed in this chapter highlights the importance of considering individual differences in self-esteem and locus of control in understanding people’s behavioral and endocrinological responses to stress. In this way, our research contributes to a deeper understanding of the biobehavioral foundations of self-regulation .

Acknowledgments

We thank Elsa Yu for the editorial help with the manuscript. The works presented in this chapter were supported by grants from the Canadian Institutes of Health Research (CIHR) and the Natural Sciences and Engineering Research Council of Canada (NSERC) to Mark Baldwin and Jens Pruessner.