Social and Behavioral Sciences Commons^™

Effects Of Chronic Stress On Safety Processing And Physiology In The Medial Prefrontal-Amygdala-Basal Forebrain Circuit, Itamar S. Grunfeld

Dissertations, Theses, and Capstone Projects

Chronic stress increases generalization of fear to non-threatening cues, a key symptom in numerous psychiatric mood disorders. However, the mechanisms through which stress impacts safety learning remain poorly understood. To probe the relationship between stress and safety learning, this dissertation employed multiple behaviors, in conjunction with in-vivo multisite physiology during explicit safety and fear discrimination learning. In Chapter 1, I outline the role of chronic stress in driving neurological adaptations that result in generalized fear and highlight how this occurs because of impaired safety cue encoding. In Chapter 2, I show that chronic stress in the form of social defeat …

The Rise And Fall Of Dopamine: A Two-Stage Model Of The Development And Entrenchment Of Anorexia Nervosa, Jeff A. Beeler, Nesha S. Burghardt

Publications and Research

Dopamine has long been implicated as a critical neural substrate mediating anorexia nervosa (AN). Despite nearly 50 years of research, the putative direction of change in dopamine function remains unclear and no consensus on the mechanistic role of dopamine in AN has been achieved. We hypothesize two stages i n AN– corresponding to initial development and entrenchment– characterized by opposite changes in dopamine. First, caloric restriction, particularly when combined with exercise, triggers an escalating spiral of increasing dopamine that facilitates the behavioral plasticity necessary to establish and reinforce weight-loss behaviors. Second, chronic self-starvation reverses this escalation to reduce or impair …

The Vulnerability Of Chronic Stress: Implications For Feeling Like Giving Up, Miranda Jany

Theses

The feeling of learned helplessness has been associated with prolonged stress and trauma. Additionally, many previous studies have examined the relationship between stress and decreased feelings of control, such as self-efficacy and locus of control. However, these forms of control have been primarily self-reported. The present study aimed to investigate the relationships among learned helplessness, chronic stressors, and self-agency using a computer-based task. We also measured heart rate variability (HRV) during the self-agency task to assess psychophysiological correlates of these variables. Seventy-four participants completed a series of questionnaires that were used to assess lifelong stressors (e.g., exposure to natural disasters, …

Intranasal Zinc Treatment Ameliorates Behavioral Deficits Caused By Chronic Stress And Traumatic Brain Injury In Mice, William R. Kochen

Faculty Proceedings, Presentations, Speeches and Lectures

No abstract provided.

Using Social Media To Engage Toronto Communities For Resiliency And Stress Planning, Martha Ta

Theses and Dissertations (Comprehensive)

As Toronto’s low-income areas grow, the city’s neighbourhoods experience a segregation by low- and high-income, contributing to chronic stress as environmental determinants and leading to negative health outcomes and chronic diseases. This study identified Crescent Town as one of the Toronto neighbourhoods with potentially high levels of chronic emotional stress through an analysis of emotions indicated by Tweets, as well as triangulation with administrative data describing relevant neighbourhood indicators. Crescent Town community members (n=23) were engaged using concept mapping to identify existing neighbourhood stressors and assets and empowered to strategize solutions. The ten-cluster solution created with six clusters describing neighbourhood …

Exploring The Link Between Genetics, Chronic Stress, And Depression, Michael Woller

Undergraduate Research and Creative Opportunities (URCO) Grant Program

Depression is a very debilitating mental illness that affects about 7% of the American Population [1] and up to about 350 million people worldwide [2]. Since the cause for depression and the reason why some individuals are more vulnerable than others are currently unclear, studying paradigms that model depression in animals, such as the learned helplessness paradigm, is useful to explore possible mechanisms and devise new treatments. To explore a possible link between genetics, chronic stress and depression, we have exposed mice vulnerable to stress to an inescapable forced swim paradigm. During the forced swim test, the mice were monitored …

Chronic Life Stress And Change In Stress Response Functioning In Urban Youth: The Role Of Social Support And Gender, Heather M. Marshall

College of Science and Health Theses and Dissertations

Salivary alpha-amylase (sAA) has been established as a bio-marker of stress reactivity in acute stressor tasks. Much less research exists exploring whether sAA is bio-marker for chronic stress exposure, and therefore, allostatic load. Extant research is inconsistent with some evidence to support chronic stress exposure having an impact on sAA reactivity and diurnal levels of sAA, while other studies have failed to support this theory. Social support is regarded as a protective factor against stress, mental health, and physical health consequences. It has been suggested that gender may play a role in the utilization and benefits of social support networks. …

The Impact Of Chronic Stress, Traumatic Experiences And Genes On Behavior, Colten Brown

Research on Capitol Hill

Chronic unpredictable stress (CUS) alters neurotransmission and remodels neural circuits involved in learning, attention and decision making.

Glial-derived neurotrophic factor (GDNF) is essential for the function of neurons. Regulation of GDNF during stress is linked to resiliency while the inability to regulate it causes behavioral alterations.

We investigated the effects of CUS on latent inhibition (LI), a measure of selective attention expressed in this model as freezing behavior.

Trauma-Informed School Programming: Applications For Mental Health Professionals And Educator Partnerships, Brenda Morton, Anna A. Berardi Phd.

Faculty Publications - College of Education

An alarming number of children experience significant trauma or chronic stress throughout childhood, manifesting in cognitive, social, physical, and emotional impairment. These challenges are expressed in the P-12 academic setting through difficulties with behavioral and emotional self-regulation, academic functioning, and physical ailments and illness. Advances in trauma-informed care, as applied to the school environment, have inspired new hope for educators who observe first-hand the learning challenges facing traumatized children. This article defines the nature of the problem along with a guiding framework to assist educators and mental health professionals in transforming to a trauma-informed school culture.

Hair Cortisol Concentrations In High- And Low-Stress Mother-Daughter Dyads, Sarah J. Ouellette

Electronic Thesis and Dissertation Repository

Hair cortisol concentrations (HCC) are receiving increased attention as a novel biomarker of psychophysiological responses to chronic stress. I examined the validity of HCC as a marker of psychosocial stress in mother-daughter dyads characterized by high (n = 30) or low (n = 30) maternal chronic stress. Additionally, I examined whether early care and daughters’ symptoms moderated similarity of HCC levels within dyads. Finally, I examined chronic stress and early caregiving as potential mediators of children’s cortisol stability. High-stress mothers had significantly lower HCC compared to low-stress mothers. Further, HCC in daughters were significantly associated with previously assessed …

Is Burnout Solely Job-Related? A Critical Comment, Bianchi Renzo, Didier Truchot, Eric Laurent, Romain Brisson, Irvin Sam Schonfeld

Publications and Research

Within the field‐dominating, multidimensional theory of burnout, burnout is viewed as a work‐specific condition. As a consequence, the burnout syndrome cannot be investigated outside of the occupational domain. In the present paper, this restrictive view of burnout's scope is criticized and a rationale to decide between a work‐specific and a generic approach to burnout is presented. First, the idea that a multidimensional conception of burnout implies a work‐restricted scope is deconstructed. Second, it is shown that the burnout phenomenon cannot be confined to work because chronic, unresolvable stress – the putative cause of burnout – is not limited to …

Relationship Between Hair Cortisol And Perceived Chronic Stress In A Diverse Sample., Kymberlee M. O'Brien, Edward Tronick, Celia L. Moore

Kymberlee M. O'Brien

No abstract provided.

Chronic Stress Elevates Telomerase Activity In Rats, Annaliese K. Beery, Jue Lin, Joshua S. Biddle, Darlene D. Francis, Elizabeth H. Blackburn, Elissa S. Epel

Neuroscience: Faculty Publications

The enzyme telomerase lengthens telomeres—protective structures containing repetitive DNA sequences at chromosome ends. Telomere shortening is associated with diseases of ageing in mammals. Chronic stress has been related to shorter immune-cell telomeres, but telomerase activity under stress may be low, permitting telomere loss, or high, partially attenuating it. We developed an experimental model to examine the impacts of extended unpredictable stress on telomerase activity in male rats. Telomerase activity was 54 per cent higher in stressed rats than in controls, and associated with stress-related physiological and behavioural outcomes. This significant increase suggests a potential mechanism for resilience to stress-related replicative …