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Physiological responses to naturally occurring stressors: The roles of context and dehydroepiandrosterone
While HPA-axis and sympathetic responding to acute stress is an adaptive reaction, chronic activation can lead to the development of health problems. How both systems coordinate remains unclear, although recent reports on their asymmetry suggest independent responding. Hyperactive and asymmetrical acute response patterns are characteristic of physiological dysfunction; both are predictive of health problems. Acute physiological response variability is the product of interactions between individual differences and environmental contexts. The current research examined the effects of context on acute physiological responding in relation to DHEA and behavior. Study 1 examined exam-taking in college students. Exam stress significantly increased cortisol responding and increased negative affect compared to attending a lecture. Study 2, a replication of Study 1, found increased cortisol and negative affect on the exam day. Those whose cortisol increased the most tended to have low levels of DHEA, but those whose cortisol change was minimal tended to have higher levels of DHEA. Study 3 assessed cortisol and sympathetic (sAA) responding in hockey players during practice, game and rest days. Game day cortisol levels were higher compared to both practice and rest day levels, while sAA levels did not vary between days. Perceived stress and negative affect both predicted sAA reactivity on the game day. Study 4 found sAA increases, but cortisol decreases, following a sprinting activity in football players. DHEA reactivity was shown to mediate both sAA and cortisol responses, and behavioral traits of aggression and neuroticism correlated with both sAA and cortisol measures. Finally, Study 5 found no differences in cortisol or sAA levels between concert and rehearsal days in singers. Cortisol levels decreased on both days, however, following singing. DHEA and cortisol reactivity were correlated on the rehearsal day only, while traits of aggression and neuroticism were correlated with sAA and cortisol measures on both days. The current research increases our understanding of physiological stress responses by providing important links between contexts of stress, DHEA and behavior.^
Psychology, Psychobiology|Biology, Physiology|Psychology, Physiological
Beltzer, Emilie K, "Physiological responses to naturally occurring stressors: The roles of context and dehydroepiandrosterone" (2008). ETD collection for University of Nebraska - Lincoln. AAI3315883.