Grant: Discovery Grants Program - Individual

Research on the effects of stress on sexual/reproductive function is contradictory. The dominant hypothesis states that stress is detrimental to sexual and reproductive function. Chronic stress can potentially impair sexual function in females because pregnancy is very costly in terms of energy, and because young are less likely to survive in a stressful environment. Chronic stress has also been shown to impair fertility in males, but it is unclear if it affects their sexual behavior. Physiologically, the acute stress response is designed to activate the energy resources necessary for survival and to suppress all unnecessary functions, including sexual function. While the negative effects of stress on sexual function have been demonstrated in many studies, there have also been several studies conducted with both human and non-human animal samples showing that stress can also enhance sexual response. ******The overarching objective of the proposed line of research is to study the underlying mechanisms that can explain both the facilitatory and inhibitory effects of acute and chronic stress on sexual function in humans to develop a model that incorporates interactions between biological, psychological, and social/environmental factors. Mechanisms to be tested include cognitive changes (attention & distraction), sympathetic nervous system activity, and adrenal and gonadal hormones. Objectives for this study include the following. 1) Develop a model that incorporates measures of SNS activity, hormones, and cognitive changes that occur in response to acute and chronic stress to determine how these variables affect sexual responding. 2) Understand how individual differences in stress sensitivity and allostatic load affect the relationship between stress and sexual response. 3) Examine gender/sex differences in the relationship between stress and sexual response. ******A majority of the previous work on the relationship between stress and sexual function in humans has focused on measuring the psychological mechanisms that might explain this relationship, such as anxiety and distraction. In contrast, much of what is known about the physiological mechanisms involved in the relationship between stress and sexual function is drawn from non-human animal models. While the animal literature has been informative, this work has focused almost exclusively on the interaction between hypothalamic-pituitary-adrenal (HPA) axis hormones (e.g., corticosteroids) and their effects on the hypothalamic-pituitary-gonadal (HPG) axis (the HPA/HPG interaction model). The present research will test hypotheses developed from animal models on human subjects and also expand the models to include measurement of cardiovascular components of stress and sexual response and additional adrenal hormones. It will also include psychological assessments of stress and related factors.**