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Hormonal Correlates Of P50 Suppression In Socially Anxious Young Adults, Andrea M. Tountas

University of New Orleans Theses and Dissertations

Ten to 15% of the population is temperamentally shy and have elevated physiological stress responses to novel social situations. Yet, the neural mechanisms underlying this personality trait are not fully understood (Beaton et al., 2009; Schmidt et al., 1997). Efficiently attending to, acting on, and remembering relevant stimuli and filtering out less important information is critical given the sheer volume of sensory and perceptual stimuli the brain is exposed to.

Relevant stimuli that garner attention are remembered and consolidated with existing memories. Stimuli that do not warrant extended attention are ignored or habituated to in a process underpinned by cortical …

Coupling Of The Hpa And Hpg Axes, Andrew Dismukes

University of New Orleans Theses and Dissertations

The Hypothalamic-Pituitary-Adrenal (HPA) and –Gonadal (HPG) axes have been considered mutually inhibitory; however, emerging evidence supports the proposition that this might not necessarily be the case. This idea is termed “coupling,” in which the HPA-HPG axis are mutually activated or deactivated. Coupling is examined across three data sets with different time-courses of stress exposure, and results demonstrate HPA-HPG co-activation occurs. Furthermore, stress exposure influences this relationship. The discussion shows how it is physiologically possible to have positive coupling or co-activation between these axes according to complex regulatory feedback systems and overlapping neural structures. Findings are interpreted developmentally, because adolescence may …

Sensation Seeking And A Real World Stressor: Endocrine And Physiological Effects, Amber Allison

University of New Orleans Theses and Dissertations

We attempted to identify the psychobiological mechanisms that mediate the process by which the sensation seeking trait culminates in behavior. We used the Sensation Seeking Scales to assess the SS trait in individuals who expressed a desire to skydive. We obtained measures of autonomic (heart rate) and endocrine (salivary cortisol) activity before, during and after skydiving. To distinguish the contribution of novelty, we compared novices (N=29) to experienced jumpers (N=15). All jumpers exhibited HPA-axis activation; novices exhibited a prolonged response and more extreme peak in cortisol compared to experienced jumpers, suggesting that novelty contributes to an intense pattern of stress …