Stress: A Biocultural Appraisal

OKLAHOMA BAPTIST UNIVERSITY

STRESS: A BIOCULTURAL APPRAISAL

by Coltan Wayne Scrivner

A thesis submitted in partial fulfillment of the requirements for graduation with honors Department of Anthropology, History, and Political Science Oklahoma Baptist University 2014

ACKNOWLEDGEMENTS I would like to express my deepest gratitude to Professor Timothy McCollum for his guidance, invaluable constructive criticism, and encouragement throughout the entire process. Without his assistance and encouragement to write an honors thesis, this project would not have come to fruition. I am also indebted to Dr. Brad Jett for his supervision of the cortisol assay and insights into procedural techniques. Additionally, I must thank Dr. Tanner Auch for his advice on statistical methods and analysis regarding the results of the cortisol assay. Instrumental to the editing phases have been various friends and members of the Milburn Center at Oklahoma Baptist University. Their thoughtful comments and many hours spent reading over the various chapters of the thesis were crucial to the overall composition. Likewise, I am grateful to the honors committee for their thoughts and ideas regarding the direction and development of the thesis. Finally, special thanks should be given to Dr. William Dressler of the University of Alabama. His expertise in the interdisciplinary field of stress research is inimitable, and I am greatly appreciative of his willingness to serve as my external reader.

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TABLE OF CONTENTS ACKNOWLEDGEMENTS ..................................................................................... ii INTRODUCTION ................................................................................................... 1 Stress: A Biocultural Appraisal.................................................................................. 1 Biocultural Considerations ......................................................................................... 1 Salivary Cortisol Assay............................................................................................... 3 Relevant and Original.................................................................................................. 5 Project Aims................................................................................................................. 6

CHAPTER 1 .......................................................................................................... 9 A FRAMEWORK OF STRESS ............................................................................. 9 The Problem of Stress ................................................................................................ 9 Defining Stress: Physiology and Neuroendocrinology ......................................... 10 Evolutionary Considerations.................................................................................... 13 Bottlenecking ............................................................................................................. 15 Stress in Sociocultural Context ............................................................................... 17 Health Factors............................................................................................................ 19

CHAPTER 2 ........................................................................................................ 22 STRESS PHYSIOLOGY ..................................................................................... 22 The Nervous System ................................................................................................. 22 Living on the Savannah ............................................................................................ 23 Ulcers and Stress ...................................................................................................... 25 The Immune System .................................................................................................. 29 Homeostasis and Allostasis ..................................................................................... 33

CHAPTER 3 ........................................................................................................ 38 PSYCHOSOCIAL STRESS ................................................................................ 38 Worried Mice and Angry Baboons ........................................................................... 38 Predictability and Control ......................................................................................... 40 The Human Hierarchy ............................................................................................... 41 The Poor Stay Poor ................................................................................................... 44 Coping and Letting it All Out .................................................................................... 46 Perspective, Perspective, Perspective .................................................................... 48 Relative Income ......................................................................................................... 49 The Hierarchical Instinct and Cultural Consonance .............................................. 50 Income Inequality and Social Capital ...................................................................... 51 #FirstWorldProblems ................................................................................................ 52 Looking Forward ....................................................................................................... 54

CHAPTER 4 ........................................................................................................ 56 CORTISOL EXPERIMENT.................................................................................. 56 COLLEGE EXAMS AS A CULPRIT FOR PSYCHOSOCIAL STRESS ............. 56 Introduction ................................................................................................................ 56 Materials and Methods .............................................................................................. 58 Results ........................................................................................................................ 61 Discussion ................................................................................................................. 62

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CHAPTER 5 ........................................................................................................ 66 CONCLUSIONS .................................................................................................. 66 Now What? ................................................................................................................. 66 The Love Hormone .................................................................................................... 66 Pick a Hierarchy......................................................................................................... 68 Remember the Basics ............................................................................................... 69 Find the Inner Zen ..................................................................................................... 69 Concluding Remarks ................................................................................................. 70 Bibliography ............................................................................................................... 72

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“Our species needs, and deserves, a citizenry with minds wide awake and a basic understanding of how the world works.” – Carl Sagan

INTRODUCTION Stress: A Biocultural Appraisal Every member of the human species has experienced what is commonly referred to as “stress.” In an effort to address when, how, and why stress occurs, entailing both its biological character and sociocultural context of occurrence, this thesis project will explore the origins of what scientists call the “stress response,” establish a working understanding of stress, and investigate human physiological implications of acute and chronic stress. In doing so, it will examine the intersection of sociocultural and endocrinological dynamics with regard to the aforementioned stress response. To support the thesis, a biocultural experiment was conducted that provides a concrete demonstration of the physiological effects that psychosocial stress imposes upon the human body.

Biocultural Considerations Stress is an ambiguous word with folk uses that are often misapplied with regard to sociocultural situations, such as poor time management, that may not actually trigger an actual biological stress response. There are, however, sociocultural contexts in which the biological stress response is activated, unleashing a flood of hormones that are intended to prepare us for “fight or

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flight,” as the cliché goes. In these contexts, our body undergoes a radical shift in physiological functioning. Heart rate increases, blood vessels restrict in the limbs to increase blood pressure, and hormones such as cortisol and adrenaline flood the body. Cognitive functioning is also affected during a stressor. The prefrontal cortex is suppressed, concomitantly suppressing processes such as concentration, rational thought, and working memory. When envisioning the treacherous world in which our ancestors dwelled, it becomes evident how biochemical changes that bias an individual to instinctually react (rather than reason or rationalize) could afford distinct advantages when faced with physical danger. Thus, it is apparent why these abrupt physiological changes were selected for, both in humans and other vertebrates, throughout time. The problem with this response today is that it can be triggered in the absence of any physical danger. Furthermore, the society in which humans live can construct “stressors” that trigger this biologically rooted reaction. Situations such as job security, paying the bills, and college exams may all spark the stress cascade. It is easy to see how chronic exposure to biological processes such as elevated blood pressure, obstruction of prefrontal cortex functioning, and prolonged mobilization of glucose can be detrimental to health. Stress is cited as a promoter of a myriad of diseases, including asthma, obesity, diabetes, headaches, heart disease, depression, gastrointestinal issues, Alzheimer’s, accelerated aging, and, ultimately, premature death. The World Health Organization (WHO) cited approximately 500 million obese individuals worldwide (not including another 900 million who are “overweight”) and over 17 million global deaths from heart disease (of which obesity is a promoter) in 2008. 2

With these numbers in mind, it becomes obvious how stress, as a promoter of these ailments, is a health concern on a global scale. The exacerbation of these numbers is not due to the physical stress that our ancestors relied upon, but rather the chronic, sociocultural-induced stress that plagues humanity today.

Salivary Cortisol Assay An institution in which a sociocultural-induced stress response is likely to be common is in a school, wherein stress can be observed in students during examinations. In an effort to support this claim, a salivary cortisol assay was conducted on saliva samples collected from physiology students immediately prior to and following a scheduled examination. A salivary cortisol assay allows for the quantitative determination of cortisol concentration in saliva samples. Cortisol is an abundant circulating steroid and the major glucocorticoid secreted by the adrenal cortex. Measurement of salivary cortisol levels serves as an indicator of hypothalamic-pituitary-adrenal (HPA) axis activation, which will be discussed in more detail in chapter two. One of the biggest psychosocial stressors that can occur is the loss of predictability and/or control. Oftentimes, students may feel adequately prepared for an exam, but come to find, halfway through the exam, that they are not as prepared as they believed. This dissonance between expectation and reality represents a lack of predictability and, thus, control. Students recorded in the pre-exam questionnaire how prepared they felt, on a scale of 1-10, for the exam. Upon completion of the exam, students recorded how prepared they felt they actually were now that they had taken the exam. The hypothesis being tested is 3

that if students record a loss of confidence during the exam, signified by a lower rating of preparedness after the exam than before, then the stress response will be activated and marked by a rise in salivary cortisol in the post-exam sample. Regarding the specifics of the experiment, the assay conducted was a competitive binding assay, which involves a 96 well plate with antibody attached in each well. Cortisol in saliva samples competes with a fixed amount of horseradish peroxidase-labeled cortisol for binding on mouse monoclonal antibody in each well. The antibodies bind exclusively to one particular entity, which, in this case, will be cortisol. The cortisol in the samples is a more pure form, and will be bound preferentially by the mouse monoclonal antibody. Following the binding, a substrate is added to each well and the samples undergo a color change. The plate is inserted into a plate reader, which measures color intensity. The color indicates the amount of horseradish peroxidase-labeled cortisol. Thus, the inverse measurement indicates the cortisol concentration in the saliva sample. Given the participation of human subjects, a proposal was prepared and submitted to the Oklahoma Baptist University (OBU) Human Subjects Committee for approval prior to any sample collection. The rationale for choosing physiology students as subjects was based on the likelihood that those students would have prior exposure to experimentation, and would thus be more comfortable with, and/or be more accustomed to engaging in experiments. In addition, many students in physiology are nursing majors and thus will have a similar schedule, being exposed to similar school-related stressors. Any experiment involving human subjects involves tremendous variation and numerous variables, but 4

choosing students with a similar college experience helps control for some of the variation. In addition, a questionnaire was administered before each sample collection to help account for individual differences and sample enrichment.

Relevant and Original The project may be deemed relevant and original in three expressed ways. First, the study of stress has expanded rapidly in the past decade. Indeed, stress is a pressing concern in contemporary societies around the world, though perhaps more so in some than in others. While some experiments have been performed involving college students, none could be found that analyzed loss of predictability in relation to cortisol levels during an exam. Most studies of this kind have only analyzed group levels before and after and exam, and not what might underlie individual differences. Second, upon searching through the archives of OBU honors theses, several observations were made: (1) those in biology or biochemistry have tended to address a single protein or molecule to which most people cannot immediately relate; (2) those in anthropology (or those addressing sociocultural matters in general) were relatively few; and (3) even fewer that might be deemed to be interdisciplinary in character. With these considerations in mind, through engaging and integrating two disciplinary arenas, namely anthropology and biology, the thesis will serve as an attempt – however modest – in addressing the aforementioned questions regarding the pressing concern of stress, its varied expression, and the expansion of research. The thesis is also on the leading edge of, and situated 5

firmly within, the anthropological tradition, is interdisciplinary in character, and employs a holistic approach with the proper scope necessary to address the inherently interdisciplinary subject of stress. Finally, this project is rather colloquial in nature1. This is not to say that it is lacking in scientific or academic rigor. On the contrary, it involves some of the most up-to-date information on stress. The motivation for writing a colloquially centered thesis is based in the unfortunate, yet obvious, lack of communication between the scientific community and the public. Complicated subjects, such as stress, are poorly communicated to the public and result in misinformation and misunderstanding. This thesis attempts to bridge the knowledge gap by breaking down complex scientific concepts so that they may be communicated to, and understood by, the public. Stress is an important and explicitly relevant part of life. In order to prevent the chronic, psychosocial version of stress, it is imperative that one understands why stress exists and how it functions.

Project Aims One of the main endeavors is to reconcile the current theories on the stress response. Because stress is so multifarious and is a product of circumstances, the canopy of actions under which stress operates is immense. Rather than evolving in the common perception of tree trunk to tree branch style, stress has turned the archetype on its head, evolving instead out of diverse situations into one similar response. This multi-linearity is one reason stress is so

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Do not be shocked to see second person language. It is intentional. The exception to this is this introduction and chapter four, which is an experimental write-up.

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difficult to understand and control. Once we begin to unravel why the stress mechanisms exists, we can learn to appreciate the physiological intentions and begin the arduous journey into understanding how and why stress affects us today. While much of the writing will focus on background information, intending to give a proper overview of the physiology and neuroendocrinology associated with the stress response, the focus of the thesis will be on 21st century Western societal pressures that activate the stress response. Emphasis must be placed on improper activation as well as chronic activation when discussing pathology. The stress response has been ideal in the evolution and survival of not only our species, but virtually every vertebrate animal on earth. Evidence of the importance of the stress response to species survival is clearly seen within the genetic code. Molecules such as proopiomelanocortin are found in every vertebrate species, giving rise to important defense peptides and hormones like Adrenocorticotropic hormone (ACTH), also known as corticotropin. The fact that these genetic sequences have been conserved for hundreds of millions of years and serve as a defensive mechanism in all of these animals is a testament to its significance for survival (Nesse, Bhatnagar, & Young 2007, 966). It was with these sights in mind that the cortisol experiment was designed, serving to illuminate possible sociocultural pressures that elicit the physiological changes of the stress response. After proper priming on the aspects of the stress response, the writing will dive into an analysis of the novel experiment designed to examine cortisol levels in a group of physiology students before and after an exam. While this may seem 7

to be an experiment with narrow sights, it will prove to be a window into something much bigger. More experiments need to be conducted in various other social settings, such as work environment, in order to broaden scientific understanding of this convoluted subject. With the emerging discoveries in the field of epigenetics, and diseases unique to developed countries arising, studies on stress are needed now more than ever. Insight into this phenomenon and how it can affect our lives can lead to improvements in our physiological health, psychological health, and society as a whole.

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“We’ve evolved to be smart enough to make ourselves sick.” – Robert Sapolsky

CHAPTER 1 A FRAMEWORK OF STRESS The Problem of Stress If ten people were asked to define biological “life,” there would likely be ten very different answers. Answers would be riddled with words like “cells,” “reproduction,” “energy,” and “responsiveness.” The best answers would consist of tenets rather than strict definitions, however all would be lacking a comprehensive description of what “life” truly entails. Although the tenets of life are fairly well established, leading biologists cannot agree on a definition due to the extreme intricacy and convolution involved. Indeed, biology has demonstrated that exceptions and caveats are inevitable when considering a complex system. Much as life itself, stress is a multifaceted biological reality with a definition that is difficult to pin down, especially when situated amidst the sociocultural context of the human condition. Within the scientific community, a proper definition of stress involves the consideration of a number of synergetic tenets, and herein rests the problem in defining it: Stress does not have a consistent classification and society often misinterprets its nature. Its complex character, coupled with common folk misunderstandings, is not conducive to progress

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toward understanding. Therefore, before a discussion of stress can occur, working criterion for stress needs to be established.

Defining Stress: Physiology and Neuroendocrinology Every person, at some point in his or her life, has felt “stressed.” But what does it mean to be stressed? Stress as a concept has a lingering disparity between public and scientific circles. It is a common belief among the public that pressure in work, school, or social life is, in essence, stress. Though the public and the scientific concepts will overlap on occasion, the scientific community has a markedly different take on stress. To borrow a definition from Koolahaas et al. (2011), ”stress should be considered as a cognitive perception of uncontrollability and/or unpredictability that is expressed in a physiological and behavioral response.” Key to this definition is the word perception. Perceived uncontrollability not only means that we do not have to be undergoing a physical stressor to activate a physiological change, but that we really do not have to be undergoing anything at all. Simply thinking about something too much can trigger the neuroendocrine cascade leading to stress.2 The improper, chronic activation of the stress response is an unfortunate result of sophisticated human sociocultural constructs. Improper activation will be the focus of the thesis, but consideration of an improper activation first requires an understanding of normal functioning.

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This concept of perceived uncontrollability and/or unpredictability will be explored in detail in later chapters.

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The stress response worked wonders in the lives of our ancestors and, no doubt, permitted the survival of our species. In the face of a predator, the physiology of our ancestors immediately underwent change: their heart rate increased, breathing rate increased, blood vessels constricted, perspiration began, blood flow to the kidneys and digestive system decreased while blood flow to the limbs increased (especially in the legs), glycogen stores began to break down into glucose, insulin secretion depleted, the immune system suppressed, and the bladder and bowels evacuated (Sapolsky 2004b, 11). Considering the circumstances of a physical stressor, all of this makes sense. When encountering a threat, you want all of your energy to be focused on survival. Relatively long-term projects, such as digesting your mammoth burger, are not important when staring down a saber-toothed cat. You would want as much glucose as possible to inundate your limbs – your key to escaping or eliminating the threat. You want to be able to access and deliver energy as fast as possible, hence the cardiovascular changes. You also want to rid yourself of as much dead weight as possible, discarding anything that has already been digested. The vertebrate body has done a remarkable job at adapting in order to survive physical stressors. In order to understand how these physical stressors – or just thought – can translate into a physiological change, it is important to first recognize the central players in the stress response. Situated within the brain are the hypothalamic-pituitary-adrenocortical (HPA) and sympathetic-adrenomedullary (SAM) axes (Koolhaas et al. 2011, 1292). Other areas of the brain are most certainly involved in the stress response, but the SAM and HPA axes are the most critical due to the precursory 11

hormones they release. Figure 1 depicts, in the form of a flow chart, what goes on at the first sign of a stressor.

Figure 1. The hypothalamus is first activated, followed by the rest of the HPA axis and the SAM system. SOURCE: www.howstuffworks.com

As stated by the name, the HPA axis includes interactions between the hypothalamus, pituitary gland, and adrenal gland. At the first sign of a stressor – before you are even cognizant of it – the hypothalamus releases corticotrophinreleasing hormone (CRH) to the pituitary gland through its private circulatory system, which in turn releases the hormone adrenocorticotrophin (ACTH) – also known as corticotropin – into the main circulatory system where it activates the creation and release of glucocorticoids, such as cortisol, from the adrenal glands

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(Olson et al. 2011, 92). This, in turn, is why cortisol serves as a common biomarker for stress. The other axis that is concomitantly activated with the HPA at the first sign of a stressor is the SAM. The SAM is a part of the sympathetic nervous system and is responsible for the physiological changes during a stress response. The hypothalamus activates the SAM, stimulating the release of hormones such as epinephrine and norepinephrine. These two hormones upregulate physiological factors (i.e., heart rate, blood pressure, perspiration, breakdown of glycogen, etc.) that prepare one for fighting, fleeing, feeding, or fornicating – sometimes referred to simply as the “Four F’s” in reference to the function of the hypothalamus (Sapolsky 2004b, 22). Indeed, these hormones – and the contexts in which they occur – have proven vital to the evolution and, ultimately, to the survival of our species: Homo sapiens sapiens.

Evolutionary Considerations While the stress response has evolved over tens of millions of years, only recently have creatures – namely, humans – has been able to elicit a stress response by psychological means (vis-à-vis sociocultural context) rather than from strictly confronting the travails of the Four F’s. The relatively rapid evolution of intelligence (via cognition) in humans allowed for technological advancements and a life of relative leisure compared to both our ancestors and other animals. This, however, begs a rather obvious and pertinent question: Why did human intelligence evolve so quickly relative to other products of evolution, while the biological character of the stress response seems to have remained the same? 13

The exact answer to this question will likely never be pinned down, however there are some very good theories about how and why this might have happened. It should be understood that intelligence, from an evolutionary and genetic standpoint, is not much different in character than speed, strength, or charming tail feathers. All of these traits might assist with some aspect of passing on your genes. Random genetic mutations will allow for variance within these traits, while the social and natural environment will choose which variations are the best suited. Traits, or variations of traits, that keep an individual alive and increase chances of reproduction from a standpoint of sociality and/or vigor will be “selected” for their expressed advantage(s). Over time, the genes that produce these traits will be passed on more frequently than those that do not, thus creating a change in the makeup of the genetic pool.3 It is important to remember that the success of a trait is only relative to the context of the environment. It is for this reason that diversity and recessive traits are important to the continuation of a species – as those traits might prove to be advantageous in the future even if their phenotypic expression (i.e., an observable physical or biochemical characteristic) currently presents a disadvantage. This is still begging the question of why intelligence evolved so rapidly, especially considering it is selected for/against in the same manner as other traits. Part of the answer lies within the mutability of Deoxyribonucleic acid, or DNA. DNA is a very stable molecule that entails several proofreading

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The genetic pool is the entire genetic makeup of a population. When concerning one gene, it is the collection, or “pool,” of the genes to which each individual counts as one piece of the pool.

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mechanisms during replication. Because of the precision of the proof reading mechanisms, genetic mutations only occur about once every 2.2x10-8 nucleotides per organism, or one in every 220 million nucleotides (Roach et al. 2010, 638).4 With ~3.2 billion nucleotides in the genome, this confers approximately seventy new mutations per diploid genome (i.e., for each new child). Given the relatively short amount of time in which human intelligence evolved, it unlikely that random mutation alone could account for human intelligence. To address this problem, a genetic phenomenon known as bottlenecking must be consulted.

Bottlenecking When applied to genetics, a bottleneck is some event that greatly reduces the number of individuals in a population. In evolution, genetic bottlenecks create punctuated effect along the evolutionary tree of life, essentially throwing evolution into hyper-drive. What might have taken millions of years to take effect – or never even taken effect – may only require tens of thousands of years in light of a bottlenecking event. Many times a bottleneck event will eradicate individuals that cannot adapt to the new circumstances while those who can adapt will survive. As you can imagine, a one-time catastrophe that destroys a large percentage of a population can cause major genetic drift and significantly lower genetic variability.5 This type of bottlenecking is a bit of a double-edged sword – while it often leaves the most well adapted behind to reproduce, the reduction in genetic 4

This means that a mutation in a single nucleotide, also called a point mutation, occurs about once in every 220 million times. 5

Many experts believe that cheetahs, which have very low genetic variability, may have undergone a genetic bottlenecking event in the recent past.

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variability can leave the ensuing population much more susceptible to other disasters, including disease.6 Graduate schools use academic requirements to bottleneck applicants into a smaller and more qualified group, King Leonidas and the Spartans used cliffs to bottleneck Xerxes I’s colossal Persian army into a nearly single-file line, and a super volcano may have served to bottleneck human populations and thus ratchet our intelligence. The Toba eruption that happened ~ 74,000 years ago is one of the largest volcanic eruptions ever, possibly lasting up to two weeks, depositing up to 500 cubic miles of magma, and launching a monstrous plume of ash over twenty miles into the sky (Rampino and Self 1992, 50). This ash cloud, in collaboration with the copious amounts of aerosols resulting from the explosion, is purported to have dropped average global temperatures by over 40° F (51). There is a casual connection between climate change and volcanic activity that operates in both directions; it is suggested that global cooling (thus, ice creation) followed by a melting of ice can promote volcanic activity by removing weight, and consequently, pressure, off of landmasses (Kutterolf et al. 2012).7 In turn, the volcanic activity promotes further global cooling through ash clouds (and possibly more surface ice melting, which would lead to more volcanic activity) in a sort of positive feedback mechanism that could thrust the globe into a cold transition much more quickly than anticipated. Populations that had developed highly organized social dynamics might have had a better chance of 6

On a microcosmic level, the power of variety comes in to play with our immune system, which will be discussed later in Chapter 2. 7

Essentially, ice melts off the land and raises sea levels. This simultaneously removes pressure from the land while adding pressure to oceanic tectonic plates. This change in pressure can force magma to ascend into new locations, thus promoting volcanic activity.

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surviving this climate change than populations that had less sophisticated cooperation skills. There is disagreement among the scientific community about the significance of the Toba eruption on faunal and floral bottlenecking. Opponents to its significance claim that the evidence for a significant bottleneck is lacking and that modern humans in Africa were already incredibly adaptable and complex to the point that the Toba eruption would not have had a major effect on their survivability (Gathorne-Hardy and Harcourt-Smith 2003, 228-9). Proponents of the bottlenecking effect of the Toba eruption argue that a climate change of such severity would select for small populations of humans that had evolved more complex social skills, while also pointing to genetic studies that suggest a bottlenecking effect ~70,000 years ago (Ambrose 2003, 235).8 Given the genetic evidence, it is a reasonable hypothesis that climate change, perhaps through drought instigated by the Toba eruption, did have some sort of punctuated effect on human evolution.9

Stress in Sociocultural Context Regardless of the specifics regarding human cognitive evolution, it is evident that the rapid evolutionary changes resulting in increased cognitive capacity among Homo sapiens sapiens did not allow time for the stress response

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Complex social skills tend to correlate with higher intelligence, suggesting that changes in climate selected for populations with higher intelligence based on their ability to work together. 9

It is important to keep in mind that many other punctuated events had a summation of effects on human evolution. I am simply supporting the idea that the Toba eruption was a larger than normal bottlenecking effect.

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to keep pace with the concomitant emergence of expressed psychological dynamics and pressures related to ever more complex sociocultural contexts. Nevertheless, it also follows that “social stress” would arise out of a bottleneck effect that selected for the most socially adept populations of humans while being less specific regarding other biological differences. However, instead of a slow genetic drift that might have allowed time for the stress response to co-adapt with complex social interactions, there was a relatively abrupt change. This speaks to the Janus-faced character of genetic bottlenecking: We are now a highly intelligent species harboring sociocultural complexity, but our physiology seems to lag in certain situations. Oftentimes our physiology can be found in conflict with our ability to think abstractly and conduct our lives in sociocultural contexts that are very different in character from any other organism on the planet. In the twenty-first century human beings have found themselves in a perplexing situation. We have reached the degree of leisure that, when combined with incredibly evolved cognitive abilities, we become “stressed” from abstract and, in some cases, arguably artificial stressors. Although today we are no longer confronting saber-toothed cats, we are regularly confronting concerns regarding employment; credit card, automobile, and mortgage payments; and in the case of students, upcoming examinations, term projects, and the impact that the next few years in college may have on the rest of their lives. While none of the above should be taken lightly, given our stress response has not evolved to deal with the psychological stress related to our perception of non-physical threats, it has fallen victim to the so called “law of unintended consequences,” resulting in

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outcomes not intended.10 Increased heart-rate, depletion of insulin, increase in blood-glucose levels, and suppression of the immune system are beneficial with regard to the Four F’s, but are not so helpful when worrying about whether or not you can provide food to your children, or whether or not you will perform well enough on your MCAT to be accepted into medical school. In fact, these psychological stressors and the physiological effects they entail, when chronic, are a real threat to health.

Health Factors A common folk notion often mentioned is that “too much stress” can make someone sick. While stress does not make one sick per se, chronic and unrestrained stress can promote disease, given long-term exposure to the physiological expressions experienced during the stress response are conducive to disease. It is for this reason that chronic stress is cited as a promoter of health disorders such as asthma, obesity, diabetes, headaches, heart disease, depression, gastrointestinal issues, Alzheimer’s, accelerated aging, and – ultimately – premature death. As of March 2013, the World Health Organization (WHO) estimated there to be 500 million people worldwide who are obese – not including another 900 million who are overweight.11 WHO estimates in 2008 also stated that there were

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The law of unintended consequences is an idiomatic warning suggesting that interference with a complex system, such as evolution, will often produce unforeseen outcomes, for better or worse. 11

Determination of overweight and obesity is based on a person’s body mass index (BMI). BMI is 2 defined as weight in kilograms divided by the square of height in meters – kg/m . WHO defines

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over seventeen million global deaths from heart disease. In both of these instances, stress acts as a promoter, thus a significant factor, contributing to human obesity and heart disease. With these numbers it becomes obvious how stress should be a matter of global concern. It is also important to understand, however, that some acute stress is not expressly harmful, and that it can, in fact, be a very useful response. The chronic and unrestrained form of stress, which promotes health disorders such as obesity and heart disease, should be the ultimate concern. It is relatively simple to draw cause and effect correlations between stress and certain ailments.12 It is an infinitely more arduous task to elucidate the cascade of changes that occur at the molecular level during a stress response. Experts from the fields of psychoneuroimmunology and neuroendocrinology are on the frontlines of this effort. The incredible efficiency of the human body, however, does not make things easier for these avid scientists. The body displays an extraordinary ability to reuse and repurpose molecules depending upon the needs at that time. This characteristic inspires great awe and admiration from scientists, but also makes their lives a living nightmare from time to time. The following chapter will make a modest effort to explain and simplify many of the physiological and neuroendocrinological changes that occur during stress. It is a complex matter, but will prove to be both interesting and essential

overweight as a BMI of 25 or greater and obese as 30 or greater. To give a visual, a man who is 6ft. tall and between 185-215lbs is overweight; greater than 215 would be considered obese. 12

It is also prone to error and misunderstanding, as this casual miscorrelation has led to many of the folk notions about stress.

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to understanding the stress response – especially understanding it as it is situated within our contemporary, sociocultural context.

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“Nature is trying very hard to make us succeed, but nature does not depend on us. We are not the only experiment.” - Richard Buckminster Fuller

CHAPTER 2 STRESS PHYSIOLOGY The Nervous System Imperative to an understanding of the stress response is a primer on the nervous system. The nervous system is broken up into two divisions: the central nervous system (CNS) and the peripheral nervous system (PNS), sometimes referred to as the sensory nervous system.8 The central nervous system includes the brain and spinal cord while the peripheral nervous system encompasses everything else, acting as a reporter for the CNS. The PNS is subdivided into the somatic and autonomic nervous systems. The somatic nervous system deals with the musculoskeletal system and conscious action whereas the autonomic deals with the unconscious functions of the organs.9 Finally, the autonomic system is divided into the sympathetic and parasympathetic systems, which act in opposition to one another. The sympathetic system’s functioning includes changes such as an increase in heart rate, dilation of pupils, stimulation of epinephrine secretion, and inhibition of

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There is, of course, not a physical division of the systems. The division is an artificial one designed to organize the system into different parts based on function. 9

The autonomic nervous system is also known as the visceral nervous system. In grade school, these were probably taught as the “voluntary” and “involuntary” nervous systems, alluding to their respective functions.

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digestion amongst a myriad of other things;10 the parasympathetic system performs the converse: slowing of heart rate, constriction of pupils, and stimulation of salivation and digestion (Sapolsky 2004b, 21-22). It is an endocrinological battle of excitation and relaxation. Put simply, the sympathetic nervous system “turns on,” or mediates the stress response and the parasympathetic nervous system winds it down. Hormones are crucial to the stress response. The vast assortment of hormones released during a stress response is overwhelming. A few important ones and their functions include: the pancreas secretes glucagon, which mobilizes glucose in the blood by triggering the breakdown of glycogen (stored glucose); the pituitary gland releases prolactin and endorphins which act to suppress reproduction and pain, respectively; also, important hormones such as insulin, estrogen, progesterone, and testosterone are all inhibited (Sapolsky 2004b, 32). The adrenal glands release epinephrine (adrenaline), norepinephrine, and glucocorticoids. These kinds of changes make sense in the event of physical danger or capturing food. Available glucose is essential to fuel physical activity, pain suppression is important for short-term survival during a physical altercation, epinephrine gives you a jolt of energy, and inhibition of irrelevant hormones is key to efficiency.

Living on the Savannah

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If you recall the sympathetic adrenomedullary (SAM) system from chapter one you will notice that it controlled these same changes. The SAM system is a functional part of the sympathetic nervous system, hence the “sympathetic” in its name.

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Imagine, if you will, a lioness in pursuit of a wildebeest. The stress response kicks off in both animals with the first pounce of the lioness. The hypothalamus secretes CRH in direct route for the pituitary gland, which triggers ACTH to be released in order to stimulate adrenal glands. The adrenal glands release an array of hormones, including epinephrine and norepinephrine. Both of these hormones cause an acceleration of heartbeat and constriction of blood vessels, which gives both animals an edge during the pursuit. Pupils in both animals dilate, increasing absorbed light and, therefore, vision. Glycogen hydrolysis (glycolysis) is initiated, supplying the body with glucose to be broken down into the body’s readymade fuel, ATP. Digestion, salivation, sex cell production and a myriad of other projects that are not immediately relevant to dinner for the lioness and survival for the wildebeest are inhibited in an effort to divert energy usage to more immediately important parts of the body, namely, the leg muscles. Let us assume that the lioness finally caught the wildebeest. She has exploited copious amounts of energy in an attempt to secure her meal. Now that she has settled down with her carcass, the switch is flipped; her sympathetic nervous system shuts off and the parasympathetic kicks into gear.11 The parasympathetic system relaxes the blood vessels, thereby lowering blood pressure, slows the heartbeat, and stimulates salivation and digestion – all critical during and after a meal. Insulin production begins again and is secreted by pancreatic β-cells as a response to an increase in blood-glucose

11

Fortunately, evolution has tweaked the areas of the brain that control these two systems to ensure that they cannot be simultaneously active (Sapolsky 2004b, 23).

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concentration. The insulin then triggers other cells to take up glucose and store it as glycogen, effectively lowering blood-glucose levels to states even lower than they were before the meal. Flipping the scenario on its head, wherein the wildebeest gets away, the parasympathetic nervous system would still kick in for both animals soon after the chase. The wildebeest would then continue grazing in order to replenish lost energy and prepare itself for the next of the savanna stressors.

Ulcers and Stress Stomach (peptic) ulcers have a long, back-and-forth history in medicine. It was believed originally that stress somehow caused them, and, up until the 1980’s, doctors did not have much advice to offer patients who were suffering from a peptic ulcer. However, when Marshall and Warren showed that a Helicobactor pylori bacterial infection caused peptic ulcers, doctors could finally prescribe medication instead of telling people to just take it easy for a while (Stress: Portrait of a Killer 2010; Marshall 2001).12 After repeat studies were done, everything seemed conclusive and, for a while, the problem of ulcers was solved. However, it was later discovered that a large portion of the population carries H. pylori in their stomach, but do not exhibit ulcers (Stress: Portrait of a Killer 2010; Sapolsky 2004b, 86). How could this be? Though it is poorly

12

As with any big breakthrough in science, everyone is a skeptic. After being laughed at for his postulation, Marshall actually swallowed some H. pylori to prove his hypothesis. Scientists eventually began to experiment with the bacterium and found that he was actually correct. H. pylori causes ulcers by weakening the mucosal lining, allowing stomach acid to come into contact with the stomach lining.

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understood, it seems there is a stalemate battle going on in the stomach of people with H. pylori – that is, until you become stressed. Let us assume you are one of the majority of people on earth who has H. pylori living in your stomach. The bacterium probably colonized your stomach long ago, but you have not noticed anything out of the ordinary. Suddenly, there is a tragic psychological stressor in your life - you lose your job, fail an important final, your significant other terminates the relationship – pick your poison. After a few weeks, your social life begins to improve and you are feeling better about yourself, except for the excruciating stomach pains you are experiencing, especially after eating. You decide to see a doctor and are prescribed an antibiotic to fight off an H. pylori infection. What happened? Because a psychological stressor can cause a physiological stress response, your sympathetic nervous system is kicked into gear at the onset of the stressor. As mentioned before, one physiological change that occurs with the activation of the sympathetic nervous system is an inhibition of digestion. When the body is eliciting a stress response, cortisol is released in copious amounts. As a glucocorticoid, one of the properties of cortisol is anti-inflammation. This anti-inflammatory property works by inhibiting the synthesis of a group of compounds known as prostaglandins. More specifically, glucocorticoids prevent the synthesis of arachidonic acid, a precursor to prostaglandin, by inhibiting phospholipase A2 action (Harvey & Ferrier 2011, 214).13 But what does this have to do with ulcers?

13

Non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin, also work by inhibiting prostaglandin production.

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As it turns out, a particular prostaglandin known as PGE2 is responsible for regulation of both stomach acid secretion and mucous secretion. As with many compounds in the body, PGE2 will have varying effects depending upon the receptor to which it binds.14 If PGE2 binds EP3 receptors, acid secretion is inhibited; if it binds EP4 receptors, acid secretion is stimulated and mucous secretion is stimulated (Dey, Lejeune, & Chadee 2006, 617-8).15 This mechanism makes sense, as an increase in stomach acid would warrant extra mucous to protect the stomach lining. On the same note, if stomach acid secretion is down (PGE2 binding EP3), the body is going to conserve a little energy by making cuts on mucosal production. An analysis of this information reveals a few key points. First, it is known that cortisol has an inverse correlation with stomach acid secretion. This means that PGE2 is binding to the EP3 receptors. So, more cortisol à less PGE2 à PGE2 binds EP3. This suggests that PGE2 has a higher affinity for EP3 receptors than it does for EP4 receptors, meaning that it will bind EP3 receptors until most of them are bound before it begins to bind EP4 receptors. Now it is starting to make sense. When you stress, cortisol concentration rises. When cortisol concentration rises, prostaglandin production decreases. Low concentrations of prostaglandin mean PGE2 will bind EP3 preferentially over EP4. This results in a slowing down of stomach acid secretion, which in turn lowers mucosal secretion. Figure 2

14

The body is highly conservative. Often the same hormone can be used for a wide range of effects depending upon the receptor to which it will bind. Think of the hormone as a skeleton key and the receptors as a bunch of old doors. The key can open any of the doors, but there can be a very different outcome depending on which door is opened. 15

It could also be the case that PGE2 binding to EP3 simply does not have an effect and in order for stomach acid to be secreted PGE2 must bind EP4.

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shows a flow chart of events, starting with chronic stress and ending in a peptic ulcer.

Chronically stressed cortisol levels stay high stops production of PGE2

Stressor gone - cortisol levels back to basal - PGE2 production begins again

PGE2 stops binding EP4 binds EP3, inhibiting stomach acid secretion and slowing mucosal production

Higher concentrations of PGE2 means it binds to PGE4, stimulating stomach acid secretion and mucosal secretion.

Helicobacter pylori takes advantage of situation and further depletes mucosal lining.

Basal level of mucosal lining is depleted due to H. pylori stomach acid eats through stomach lining - peptic ulcer forms

Figure 2. The figure illustrates the cascade of events leading to an ulcer. H. pylori becomes an opportunistic pathogen, taking advantage of the lower levels of mucous, which acts as a barrier between the stomach contents and the sensitive stomach lining.

Taking this information into account, the story above begins to make more sense, and the reason for the infection is unveiled. After a few weeks of the blues, you find a new job, ace the test, and get the girl. Things are looking up. Because things are getting back to normal, the parasympathetic nervous system begins to take on its normal hours of operation and the sympathetic finally winds down. When this happens, your cortisol levels go back to basal levels, meaning that prostaglandin production is on the rise once again. PGE2 is being synthesized in larger amounts, and it begins binding EP4 receptors, turning on acid secretion and mucosal secretion. But there is a problem. 28

Over the past few weeks your acid secretion has been down and the stomach mucosal lining has thinned, and H. pylori has been proliferating at an alarming rate. With your normal defenses down, H. pylori has had the upper hand in the battle and has virtually wiped out the remainder of your mucosal lining and infected several cells in the lining of the stomach (Sapolsky 2004b, 86). As the parasympathetic system continues stimulation of digestion, the stomach acid overwhelms the under-lined stomach and begins to, quite literally, eat through the lining, resulting in an ulcer. Stress does not cause the ulcer, but it weakens the mucosal lining, affording H. pylori an opportunity to finish clearing out the rest of the mucous and cause an infection.16

The Immune System It seems as though every finding related to stress must be taken with a caveat due to its beautifully complex – and concurrently frustrating – character. Stress and its relationship to the immune system is no exception. Does stress have deleterious effects on immune function? Yes, sometimes. As with most effects of the stress response, the emphasis seems to be on time – is the stress acute or chronic? New studies strongly suggest that acute stress can actually enhance immune function (Dhabhar et al. 2010, 8). Now this makes sense. If you are on the run from a predator, you do not have time to worry about getting scratched up; you want your immune system to jumpstart in anticipation of

16

Credit should be given to Dr. Robert Sapolsky for inspiring the stress anecdote. It was an adaptation of his hypothetical ulceration in “Why Zebras Don’t Get Ulcers” (88). His ability to portray boring biological processes in a fun (and funny) way is truly uncanny.

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lacerations at the very least.17 This would be especially true in the case of a bite or scratch during the escape from a predator. A flood of immune cells to the skin immediately preceding a potentially infectious cut could be the difference between life and death. In a less morbid example, this immune-augmenting nature of stress could be important in juvenile play.18 About an hour after activation of the stress response, the heightened activation of the sympathetic nervous system catches up and begins to suppress immunity. Continued activation of the stress response via chronic stress will sometimes cause immune function to plunge up to 70% below normal (Sapolsky 2004b, 155). Glucocorticoids, which will be discussed shortly, are likely the culprit for this. Chances are that a physical stressor will have ended well before the onehour mark. This is not the case, however, with many psychological stressors. Psychological stress arising from social conflicts, which can be referred to as psychosocial stress, will sometimes occur for days or even weeks at a time. This sort of chronic stress is dangerous and detrimental to health. Unfortunately, this is also the type of stress that commonly affects people in the Western world. Figure 1 shows a concept map of the relationship between stress, the immune response, and health outcomes.

17

Interestingly enough, a recent study has found cortisol synthesis by human hair follicles. The findings suggested that the skin may have a sort of “peripheral HPA.” This could have implications in many medical treatments, dermatological research, and stress research (Ito et al. 2009, 9). 18

It would be definitely be advantageous to have a boost of immunity during juvenile play, wherein scrapes are likely to occur.

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Fig. 1. With the exception of hypersensitivity (allergies), acute stress is generally not dangerous. In fact, research points to the conclusion that acute stress may even be beneficial. On the other hand, chronic stress is much more detrimental to health. Borrowed from Dhabhar 2009, 304.

So, why does all of this happen? Recalling the initial activation of the HPA axis, CRH is released within seconds, ACTH within minutes, but glucocorticoids take around half an hour to proliferate; glucocorticoids, known to be immunosupressors, significantly lower leukocyte numbers in the bloodstream and regulate the production of pro-inflammatory cytokines (Sapolsky, Romero, & Munck 2000, 57, 63).19 In a time of acute, physical stress, glucocorticoids would not be around to dampen immune function.20 However, chronic psychological stress leaves the glucocorticoids lingering for long periods of time. It takes much longer to clear glucocorticoids from the body than other stress hormones, so 19

Cytokines are chemical messengers for cells; the Hermes of the immune system.

20

This makes sense in light of how the stress response would have evolved. Glucocorticoids, which show up about 30 minutes after the onset of a stressor, also stimulate appetite (Sapolsky 2004b, 74). This is great timing if you just chased down a wildebeest and are preparing to eat. It is also great timing if you just burned a whole lot of calories escaping near death and now need to replenish lost fuel.

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repeated activation of the stress response leave a slow trickle of glucocorticoids that seem to stick around forever (Sapolsky 2004b, 74). Reevaluation of glucocorticoid function has revealed a possible answer to the seemingly odd phenomenon of stress-induced immunosuppression. Imagine the consequences if glucocorticoids were not present to lower immune function – autoimmune disease. The immune system would simply spiral out of control. In fact, studies on autoimmune diseases show a strong correlation between autoimmunity and glucocorticoid dysfunction, wherein there are low levels of glucocorticoids or under-responsiveness to them (Sapolsky 2004b, 156-157). When there is under-responsiveness to glucocorticoids, the HPA axis cannot properly measure circulating glucocorticoid levels, leading to an improper regulation of cytokines and leukocytes, thus leading to a greater susceptibility to a variety of diseases. (Cohen et al. 2012, 2). As research in fields such a neuroimmunology expands, scientists are beginning to realize the interconnectedness of the nervous system and the immune system. The body is a complex system, and perturbing one part of a complex system emits a shockwave effect throughout the rest. Taking these observations into consideration, the conclusion can be drawn that the stress response acts as a sort of mechanism that mediates the immune system. The immune system is a merciless entity. Without the stress response, more specifically without glucocorticoids, even we would succumb to its vigor. Luckily, the brain also regulates the circulating levels of glucocorticoids. When levels reach a certain concentration, the brain shuts off secretion of CRH, which stops secretion of ACTH, which ultimately leads to a halt in glucocorticoid 32

production (Sapolsky 2004b, 248). Therefore, glucocorticoids not only keep the immune system under control, but they also regulate their own levels via biofeedback.

Homeostasis and Allostasis If you remember much from high school biology, the word “homeostasis” probably comes to mind. The idea behind homeostasis is that the body has a single point in every system at which there is optimal functioning; the body will do everything possible to reach this “optimum point.” It is why your pancreatic β cells kick into gear after you eat a jelly doughnut and why you sweat when you exercise. Your body is simply trying to get itself back to its comfort zone. While homeostasis is a marvelous concept that beautifully explains many themes in biology, it does not quite explain stress. Change, or adaptation to change, is the key to survival and the driving force behind natural selection. If an organism can adapt to a changing environment, to changing demands, then it will survive. Once the organism has adapted to the new demands, it settles in and reaches a new level of homeostasis. When another change occurs, the organism will adapt and be subject again to a new kind of homeostasis. Imagine you are driving along a fourlane highway, enjoying some McDonald’s fries. In an unfortunate turn of events, you drop your fries on the floor and bend over to pick them up. When you look back up you realize that you are riding the line between two lanes – what do you do? In homeostasis, you swerve back into the lane you were originally in, reattaining your optimal point in the middle of the left lane. In allostatsis, you 33

continue your drifting into the right lane and set your new optimal point to the middle of the right lane. Then you continue on eating your fries. This idea of “constancy through change” (Sapolsky 2004b, 9) is the central dogma of allostasis. Allostasis does not necessarily replace the homeostatic idea; it just looks further and more broadly at the phenomenon. One example of allostasis can be seen in the glucocorticoid negative feedback loop in the brain. As previously stated, certain areas in the brain are rich in glucocorticoid receptors and will trigger the cessation of CRH secretion at a certain concentration of glucocorticoids in the blood. (Sapolsky 2004b, 248). At first, this may seem like your run-of-the-mill homeostasis at work. However, what happens when the wildebeest needs to sprint from the lioness? If his brain is keeping the resting-state levels of glucocorticoids, he will not have sufficient available energy and will be easy lunch for the lioness. When in a state of physiological stress, the brain shifts the glucocorticoid threshold point so that a higher concentration is needed before shutting off CRH production (248). This allostatic shift is essential during a stressor. It allows the wildebeest to reap the survival benefits of the stress response for an extended period of time before it is shut off by regulatory mechanisms, namely glucocorticoid concentration in the blood. While allostasis is beneficial in the short term, it can be detrimental if taken too far. Imagine you dropped your fries a second time while riding along in the right lane. Again you bend down to pick them up, and when you look up you are riding the middle of the line. This time, however, you are already in the furthest lane. If you continue your modus operandi of allostasis and keep drifting to the 34

right, you will drive right off the road. The same idea applies with bodily systems. It is okay to increase your body temperature by a few degrees to aid in immune function; but if the set point continues to escalate, it will be lethal.21 Allostasis, or its unhinged activation, could be a contributor to the onset of many diseases, including hypertension, heart disease, and type 2 diabetes, just to mention a few. Not everyone has embraced the idea of allostasis. In this thesis, and more specifically, in the cortisol experiment, I will attempt to support the link between social pressures and biological responses via allostatic change. The first major point to understand is that social dynamics do make a difference in physiology. Studies across the board associate social dynamics with the diseases that are also associated with stress, which in turn impacts physiology. The second major point is that the brain mediates the physiological changes. This is not only referring to the neuroendrocrinological aspects of the brain, but also the psychological side of stress. Psychology and biology are intricately linked together in human beings. One consequence (or benefit, depending upon your point of view and the situation at hand) of our higher intelligence is that we can react just as strongly to a psychological stressor as we can to a physical stressor. We do not need to see that our bank account is empty in order to activate a stress response – we only need to know that it will be empty before our next paycheck. This prescient state of mind is what makes us, us. It is what allows mankind to manipulate, thrive, and survive. Unfortunately, however, it seems as though it can also bring about our

21

The utility of fever is controversial, but the common theory is that higher temperatures tend to aid in immune function.

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demise when unchecked. A preemptive rise in blood pressure can be useful, but not if there is long-term activation. This is particularly true when the increase may not be accomplishing much in the presence of social pressure. The combination of the aforementioned tenets, namely the brain initiating physiological changes as a pro-active strike against undesirable social status/situations, is the main point supporting chronic stress as a promoter of disease (Sterling 2003, 17-18). The stress response is simply maladaptive for chronic socio-cultural stressors. Throughout this chapter, there has been a running discussion of the operating neurological and physiological mechanisms behind “stressing out.” There was also a brief discussion of immunology, which is becoming increasingly important to the study of stress through the fields of neuroimmunology and psychoneuroimmunology. Finally, I attempted to clarify the somewhat muddled concept of allostasis and how it applies more appropriately to stress than does homeostasis. The next logical step to take would be to discuss chronic stress as sustained through social dynamics – the topic of the next chapter. Clearly the stress response is around because it was beneficial to humanity in the past, and it continues to be important in the present. So the question arises, why is it bad? Or, to rephrase, why does the word evoke a negative connotation? I will attempt to explain this interesting phenomenon through an anthropological perspective. This will be accomplished by analyzing social undercurrents that I believe are feeding our neurological reactions to unfavorable conditions, ultimately leading to disease.22 After this analysis, the cortisol experiment will be introduced. There

22

It is important to understand that the claim that stress causes disease is not being made. Rather, stress promotes disease.

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will be an explanation of its relevance, and suggestions on what the results may be revealing about the way in which our social lives affect our health.

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“The apparent complexity of our behavior over time is largely a reflection of the complexity of the environment in which we find ourselves.” – Herbert Simon

CHAPTER 3 PSYCHOSOCIAL STRESS Worried Mice and Angry Baboons Due to very convoluted sociocultural dynamics, stress studies on humans are difficult to conduct. Humans belong to several social groups to which they assign differing levels of importance, exemplify an incredibly wide array of beliefs, and display radically different ways of living within their own idiosyncratic society. So, as with many avenues of science, the bulk of the work is done on animals. Taking one step down in sociocultural complexity to primates, such as baboons, the study becomes easier to control and conduct while still maintaining integrity. Baboons have more free time compared to many animals, leaving a large portion of the day to social endeavors. In line with this, baboons are social creatures that form hierarchies similar to those found in human sociocultural contexts. In a baboon troop there is a dominant male who gets all the goods, i.e., first access to females and food. However, life for him is not always great. No matter how important you might be, bad days will transpire. In turn, when the

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dominant baboon has a bad day, he becomes aggressive towards subordinate males.23 An outlet for frustration is one of the most important factors relating to stress (Sapolsky 2004a, 396). This may seem like a wives’ tale, but endocrinological studies have been performed on the effectiveness of an outlet for stress. For example, placing mice in an unfamiliar habitat is a method of imposing chronic psychological stress.24 Mice that have access to an inedible material, such as cardboard, in the novel habitat will gnaw on it as an outlet for their anxiety. This act of chewing on cardboard when placed in the new environment results in lower levels of stress hormones than in mice who did not have something on which to chew (Hennessey & Foy 1987, 241).25 Outlets for stress are not limited to chewing or biting, but it happens to be an effective and convenient method for many animals. On the savannahs of Africa, cardboard is scarce. Instead, Baboons have made do with the hide of a subordinate. When feeling stressed, a dominant baboon will harass and bite a subordinate (Stress: Portrait of a Killer, 2010). The lower ranking males become victims of psychological and physical abuse. There is a loss of control and predictability, which lies at the root of a stress response (Sapolsky 2004a, 396). They live minute to minute not knowing when the next lashing is coming. This loss of predictability causes the subordinate to search for

23

If you have ever been around a superior when he or she was having a bad day, you can probably relate. 24 The novel environment diminishes perceived predictability and control, thus eliciting a stress response. 25

Though not the particular focus of this thesis, more work on the hormones and outlets for stress could reveal larger insight into many common mental disorders.

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an outlet of his or her own. Typically, the outlet for any baboon is one of his subordinates. The aggression continues down the social ladder in a sort of domino effect (Stress: Portrait of a Killer, 2010). As you can imagine, the baboons at the lowest end of the hierarchy have the least amount of control in the situation, which leaves them with virtually no predictability. In addition, lower ranking baboons do not maintain the same access to outlets for their frustration as the baboons further up in the hierarchy.

Predictability and Control The importance of predictability as a factor in stress is well documented (Abbott, Schoen, and Badia 1984; Bolini et al. 2004; Koolhaas et al. 2011; Yang et al. 2011). This is true for both physically and psychologically stressful situations. While many studies are performed on rats and mice for convenience, some interesting historical studies exist on the correlation between unpredictability and stress in humans. As mentioned in chapter 2, stress tends to be highly correlated with formation of peptic ulcers. This phenomenon was exhibited in the bombing of England in WWII. London was bombed nightly, whereas the bombing of surrounding suburbs were more sporadic. The result? A substantial increase in ulcers during that time plagued the suburban population particularly, where bombings were less routine and thus less predictable (Sapolsky 2004b, 260). Though bombing certainly induces psychological stress

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within itself, unpredictability was a major determinant in the elicitation of chronic stress.26 Along with predictability, control is a big determining factor in the stressfulness of an event. More specifically, perceived control is important. As with many other avenues of stress research, shocking rats seems to be a popular method for studying perceived control. If a rat is taught to press a lever in order to alleviate a shock, and then the lever is taken away, his stress response skyrockets. That is to be expected, as he can no longer prevent the shock from occurring. However, if he is given a nonfunctional lever to press when he is shocked, his stress response is still lower than when he is shocked without a lever to press (Sapolsky 2004b, 261).27 This phenomenon could possibly be related to the placebo effect. Even when there is no proactive action being taken, believing that things are getting better (i.e. perception of control) can actually alter the outcome.28 The mind is more intrinsically tied to our biology than one might think.

The Human Hierarchy Some of the main factors in determining the stressfulness of an event have been discussed: predictability, control, and perception. The three are often 26

I would imagine that a similar study could be done on the stress effect of earthquakes on longtime California residents versus those who were just visiting. 27 On the same page, Sapolsky also gives an example involving people and airplanes. More people are afraid of flying than driving, even though there are many more automobile accidents than plane accidents. Why? People have control (or believe they do) of an automobile, while they have no control over the plane. 28

For you skeptics, if the placebo effect was not a big deal, then single blind studies would not be a required aspect of nearly all medical experiments. Often times, double blind studies are performed, in which even the physician is not aware of which treatment is being prescribed.

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tied together, and a change in one can lead to a change in others. Table 1 displays the correlation between stress and rank depending upon the context in which the stressor presents itself. The sociocultural context in which one lives determines many things about life. When it comes to stress, sociocultural context heavily influences who will be most vulnerable.

Table 1. Influence of societal characteristics on stress experienced by high- and low-ranking individuals An asterisk indicates no rank-related trend. Borrowed from Sapolsky 2005, 651.

Table 1 articulates various social situations and who is most stressed during those particular situations. The only instances in which a dominant individual will be more stressed than the subordinates are when the society is unstable, breeding is cooperative, or hierarchy is maintained through constant physical aggression. As for personality, the dominant individual is only more stressed than the subordinate when they are overly aggressive and subordinates

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exploit coping strategies. None of these instances are very familiar in a Western, capitalist society. Socioeconomic status is mostly stable (the rich stay rich, the poor stay poor); the hierarchy is maintained through intimidation (e.g. threat of being fired) rather than through physical altercations; and dominants tend to be proficient in exerting their control while the subordinates may not have access to coping strategies due to time, money, or other constraints. What does this mean for humans? Essentially, it means that the lower your socioeconomic status (SES), the higher your stress levels will be. This is not conjectural; the relationship between SES and illness remains an important and frequently researched topic. One study in particular, known as the Whitehall study, became the gold standard for human hierarchy stress studies. Whitehall was an enormous longitudinal study that looked at the relationship between grade levels in the British civil service and mortality rate.29 The results were astounding: a strong inverse correlation between rank and mortality. As rank dropped, the risk of dying – from any cause – increased (Marmot, Shipley, and Rose 1984, 1005). Even today there are studies that analyze the data from the Whitehall study in order to glean information about SES and health. A follow-up study, known as Whitehall II, gave little reason to rejoice. The results showed an inverse correlation between control and illness, and, to make matters worse, the correlation was maintained even after SES was taken into account (North et al. 1996, 337). Those with less control on the job sustained more absences from work due to sickness. These findings followed suit with a 29

This study was a incredibly important in understanding the relationship between economy and health. It involved over 17,000 subjects.

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host of other studies that found a similar correlation between control and illness.30 Because of the massive subject pool and ability to control for confounds, the Whitehall study served as one of the greatest tools for studying the effects of hierarchy and SES on humans.

The Poor Stay Poor The discussion thus far has culminated with the question in mind, why does the ranking system of human society, namely, SES, correlate so strongly with poor health? There is a laundry list of stressors when you are poor: money, lack of control, instability, lack of predictability, and harder work for less pay, just to name a few. Unfortunately, health issues cost money, which poor people do not have, which causes a loss of predictability, leading to instability, which causes more stress, casuing lack of sleep and a lowering of immunity, which leads to health issues… and the sequence perpetuates.

30

For studies involving control and illness, see Turner and Lawerence, 1965; Hackman and Lawler 1971; Hackman and Oldham 1975; Karasek et al. 1981; Spector, Dwyer, and Jex 1988; Karasek, Gardell, and Lindell 1987; Kristensen 1991

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Figure 1. Poverty is difficult to overcome. It seems that all of the bad characteristics of poverty lead to poor health (for which stress paves the way), which causes one to miss work due to illness. Poor people are less insured, and cannot easily afford a doctor’s visit, which can lead to a worsening or compounding condition, resulting in a triggering of the characteristics of poverty. Figure borrowed from Wagstaff 2002, 98.

Poverty is a vicious cycle from which it is nearly impossible to depart. Being poor does not just involve having less money. Less money brings with it a host of other sociocultural dynamics that tend to propagate poverty. When it comes to stress, being poor is really the worst possible situation to find oneself. Literally every characteristic of poverty is a stressor and a promoter of other stressors. Figure 1 gives a simple visual representation of how being poor keeps you poor Four of the major “tenets” of psychological stress have been mentioned: lack of predictability, lack of control, lack of coping mechanism/outlet, and interpretation of stressors (Sapolsky 2005, 396).31 The sheer nature of being poor virtually eliminates the possibility of predictability and control, but what

31

A fifth tenet, social support, will be discussed in a few paragraphs.

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about coping/outlets? As seen with the baboons, an outlet for frustration is essential to coping with stress. Can poor people overcome their stress by simply learning to find ways to cope and let out their frustration? Not necessarily.

Coping and Letting it All Out If you are wealthy and happen to be having a bad day, you might come home to your mansion from shopping all day at the mall and plop down on your new sectional couch to watch some 3D football on your 80’ LCD TV. Alternatively, you might go for a swim in your Olympic pool. There are plenty of opportunities for you to cope (you really do not even have to try). Let us go to a less excessive example. You are a middle class guy who had a rough day at work. You come home and have a snack before heading to the local YMCA to let off some steam on the racquetball court. The middle class is a much less extravagant illustration, but there is still ample opportunity for you to cope with psychosocial stress. You have enough food in the house, presumably a working vehicle, a gym membership, and time to participate in recreational activities. What about the guy who is living in poverty? He comes home from his second minimum wage job to a less than desirable house that has not been renovated since the early ‘70s. He is not a fan of the pink floral linoleum, but money is tight and he does not have time to replace it. He ate a double cheeseburger from the dollar menu on the way home because it was cheap and he was tired of having ramen for dinner. He knows it is not the best meal for his health, but it is what he can afford. He would like to go work out or enjoy some television, but he must make a decision: have a little free time and get less than 46

the recommended amount of sleep on a dilapidated mattress; or go straight to bed, have no semblance of a life outside of work, and get his full eight hours so that he will be up and ready at 6 a.m. for his job that he loathes. When you are poor, resources for coping are sparse. The time and money you do have are dedicated to matters at hand – paying the loan shark, keeping the electricity on for your family, putting gas in the car, putting food on the table. There is no room for a stress outlet in your schedule or your budget, nor will there likely be one in the future. You do not have the time or money to be planning for any kind of future when the present is overbearing. You have to focus on the now in order to try to exercise some sense of control in your life. What does not kill you will only make you stronger… unless you are poor. When you are poor, what does not kill you simply makes you less prepared to deal with the stressors of the next day. So, predictability, control, and coping are out of the question for the poverty stricken individual. What about social support? After all, who needs money to be happy when you have a strong family? Sadly, this aspect of poverty is poorly expressed by movies. Though a poverty stricken family might be a great family, there is still the restraint of money and time. Your significant other is likely working at least one job. The kids might even have a job to bring home a little more money. Even if you manage to find some free time, money is limited, so your options for bonding are lower than those of the middle class. All this to say that social support is not out of the question for the poverty stricken individual, but there are certainly more limitations than one would like.

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Perspective, Perspective, Perspective The poor appear to be running out of options when it comes to coping with stress. It seems as though the last hope for the poor is overcoming the final tenet of psychological stress: interpretation of the stressor. Two people can have two very different interpretations of the same stressor. To put it biologically, the same level of allostatic disruption can cause differing levels of stress based upon individual perception. During an unstable period in baboon hierarchy, males who are losing rank will exhibit higher levels of glucocorticoids than those who are rising in rank (Sapolsky 2004b, 263). Thus, it is not the quantitative amount of change, but rather the qualitative interpretation of that change. This might seem obvious, but it presents an important caveat – significance you place on stressful events is far more important than the reality of the event. Regrettably, the prognosis for the poor overcoming stress by interpretation is as bleak as ever. When you are poor, it is difficult to not feel poor. Even worse, how poor you feel actually has a huge impact on overall health. This is a fairly simple study: ask people where they fall on a stepwise socioeconomic chart, and run the statistical tests. Results from these studies show that not only is SES a great indicator for health, but subjective SES is as well (see Adler et al. 2000; Adler and Ostrove 1999; Singh-Manoux, Adler, and Marmot 2003). In fact, Subjective SES is just as good – or better – of a predictor of overall health as actual SES (Sapolsky 2004b, 374). This really should not be surprising. After all, it makes sense that the poorer you actually are, the poorer you will feel and visaversa. Similarly, the richer those around you are, the easier it is to feel poor.

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Relative Income When it comes to psychosocial stress, absolute poverty seems to be less important than income inequality, or relative poverty. To put it another way, people tend to prefer having more money than others around them than they do just having more money. Take the following study by Solnick and Hemenway, 1998, for example. Respondents were asked which of the following scenarios would be more ideal: scenario A, wherein you earn $50,000 per year while others averaged $25,000; or scenario B, wherein you earn $100,000 and others averaged $250,000. Surprisingly, over half of those surveyed chose scenario A. To them, relative wealth was more important than absolute wealth. The previous study is not alone. Consider Table 2 from Carlsson, Johansson-Stenman, and Martinsson, 2007, in which respondents were asked which society would be best for a future relative (e.g.: a son, granddaughter, etc.). Almost half of respondents said that their relatives were better off earning

Table 2. In the experiment, there were three different versions of “society R” tested. The average exchange rate in 2007 for SEK – USD was 1SEK = 0.148 USD (http://www.xrates.com/average/?from=SEK&to=USD&year=2007).

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14,800 SEK/month when others averaged 13,450 SEK/month instead of earning 27,000 SEK/month when others averaged 30,000 SEK/month. In current USD, this would mean 47% thought $2,190/month, given others earn $1,990/month, was better than $3,996/month, given that others earn $4,440/month. These results represent a large disparity between the importance of absolute wealth and relative wealth.

The Hierarchical Instinct and Cultural Consonance It could be proposed that this behavior denotes something deeper. Money is the modern world’s grip on power. Ultimately, human beings are social creatures, and the hierarchical-type society of their ancestors’ past is conserved in humankind today. Rather than who has the biggest teeth, it is more about who has the biggest bank account. When others are earning more than you, you are slipping down the hierarchy. The following is a non-monetary illustration of this behavior: in which military group is morale higher: the Air Force, where promotion is rapid, or the military police, where promotion is sluggish? As it turns out, morale is higher in the military police (Stouffer et al., 1949; Merton & Rossi, 1950). As with the previous two studies, relative position was more important than absolute position. What matters most is that you do not fall behind in rank in regards to your immediate sociocultural context. Someone else in your immediate surrounding being promoted to a higher rank means that you are failing to meet your cultural model, and thus have lower cultural consonance. Cultural Consonance, a term coined by anthropologist William Dressler, refers to the degree in which one succeeds in achieving the 50

cultural model of lifestyle within their sociocultural context (Kawachi & Kennedy 1999, 224). Because income inequality exerts its affect within relative contexts, it can directly affect cultural consonance. As income inequality rises, it becomes more difficult for the less affluent to meet the demands of their socioeconomic cultural model. This may sound frivolous, but failing to meet one’s cultural model can bring along adverse health effects through psychosocial stress (Kawachi & Kennedy 1999, 224; Dressler 1996; Dressler, Baliero, & Dos Santos 1998).32 This should come as no surprise, as the discussion thus far has centered on how social dynamics can directly affect stress, which correlates to detrimental health outcomes.

Income Inequality and Social Capital Income inequality also presents an interesting relationship with a concept known as social capital. Social capital refers to the available social connections from which an individual can draw within a community. In a nutshell, high social capital would involve a high level of volunteering, several organizations covering a wide array of topics and opportunities, a high level of intercommunity trust, and social cohesion. Many of these tenets are intrinsically tied to one another, meaning a lowering of one can often weaken the others. Research has shown that greater income inequality correlates with higher rates of crime, including assault, robbery, and homicide (Kennedy et al. 1998, 14). Similarly, higher gun ownership correlates with lower social capital (Hemenway, Kennedy, Kawachi, & 32

Given the radically dynamic character of “culture,” it is remarkable that any such connection could be made with statistical significance. However, the fact that correlations can be made speaks to the truly intertwined nature of physiology and socio-psychology.

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Putnam 2001, 488). High crime rates result in lower intercommunity trust, lower social cohesion, and, ultimately, lower social capital. Thus, a community with less income inequality is likely to have greater social capital and visa-versa. All of the social dynamics mentioned in this chapter - lack of control, unpredictability, lack of coping mechanisms, subjective SES, low social capital, income inequality, low cultural consonance - are links in the binding chains of stress. Studies faithfully link some of the more obvious factors, such as income inequality, low subjective SES, and low cultural consonance, with illness and morbidity (see Kawachi, Kennedy, Lochner, and Prothrow-Stith 1997; Rodgers 2002, Wilkinson 1990; Wilkinson 1992). Stress, particularly psychosocial stress, acts as the joining segment between the sociocultural and the physiological when it comes to these social undercurrents.

#FirstWorldProblems Now what we are faced with is a sociocultural dilemma. In the Western world, and particularly in the United States, the wealthy love nothing more than showing just how wealthy they are. Income inequality has become grossly exaggerated through material substantiations, which raises the bar for cultural consonance. With an ever-growing gap between the poorest of the population and the richest, it is easier than ever for the poor to feel poor. More appropriately, it is nearly impossible for them to not feel poor. Now, on top of the consequences of actually being poor, and the stressors that come along with it, there exists the problem of feeling even poorer than one might be.

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The American society places a great deal of importance on personal wealth. As a result, success begins to be defined by how much wealth an individual has accumulated – the “American Dream,” if you will (Evans 2002, 47). Given the inverse relationship between income inequality and social capital, this conflation of success and wealth presents a problem. The American Dream, being rooted in capitalism, instills a strong socioeconomic hierarchy that is all too nostalgic of Dark Age feudalism. It creates an essential dichotomy between wealth and poverty. In one sense, from the viewpoint of stress, American capitalism is worse than Dark Age feudalism. With feudalism, peasants knew their place in the hierarchy. There was no, “get nobility or die trying,” business. It was more, “farm and put food on the table.” In 21st century American capitalism, there’s a sense that you are not rich because you are not good enough. You just are not trying hard enough. Others are outcompeting you in the socioeconomic hierarchy. It does not matter that you were born into poverty because, after all, everyone has the same opportunity, right? Perhaps the individual who figures out how to integrate capitalism and high social capital will win a Nobel Peace Prize. It is a difficult conundrum to work through, especially because trial and error is not exactly the best approach. It should be understood that capitalism is not inherently bad. More people just need to be aware of what is happening and how it all works. Just as their primate cousins, humans are hierarchical by nature. However, they are also social creatures capable of compassion and cooperation. The key is to balance these two seemingly opposite ideals. 53

Looking Forward Up to this point, basically everything regarding psychosocial stress has been horribly negative. It seems as though virtually nothing good can come out of the stress response. In the concluding chapter, there will be suggestions as to how stress may not be so bad. The next chapter, chapter four, encompasses a novel experiment that is testing for a correlation between cortisol levels and predictability in a social setting. Accordingly, this chapter appears in the format of a scientific journal article, and is very different in character from the rest of the thesis. Chapter 4 is a case study that was performed by the author at Oklahoma Baptist University. The knowledge and insight from the previous three chapters should serve as an appropriate primer for making sense of the experiment and the implications of the results. The previous chapters provide a context for chapter four, while chapter four provides a real-world example of the phenomenon discussed in previous chapters. Following this chapter will be the concluding chapter, which will involve a discussion on coping strategies and possible courses of action given the knowledge from the preceding chapters. Finally, it will sum up the thesis and provide a capstone for the understanding of stress within the sociocultural context. The concluding chapter follows chapter four. It will involve a more optimistic outlook on the stress response, including a discussion on coping strategies and the . Perhaps if psychological stress is created in the mind, then

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there exist certain strategies that can circumvent current sociocultural troubles. There will also be a discussion of oxytocin and its role in the stress response. Hopefully, the concluding chapter will lighten the mood and provide a less morose outlook on stress and the overall human condition.

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“Life is infinitely stranger than anything which the mind of man could invent. We would not dare to conceive the things which are really mere commonplaces of existence.” – Sherlock Holmes (Sir Arthur Conan Doyle)

CHAPTER 4 CORTISOL EXPERIMENT COLLEGE EXAMS AS A CULPRIT FOR PSYCHOSOCIAL STRESS

Introduction In the early 1900s, physiologist Walter Cannon, coiner of the term “fight or flight,” was developing ideas on stress and laying the groundwork for the field of stress physiology (Cannon, 1916). With the work of Hans Selye and his development of the General Adaptation Syndrome in the 1930s, stress physiology accelerated as a major field of scientific inquiry. In the late 1960s and early 1970s, the famous Whitehall study found a steep inverse correlation between British civil service grade level and mortality rate (Marmot et al., 1984). With a sample size of over 17,000, these results merited investigation into the association between socioeconomic status and health. Modern work on stress has extended into the realms of anthropology, psychology, neurology, endocrinology, immunology, and even amalgamating into recently introduced fields of psychoneuroendocrinology and psychoneuroimmunology. An improved understanding of psychosocial stress remains vital to the current understanding of how stress affects people today.

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Psychosocial stress – defined as a physical instantiation of the stress response arising from cognitive appraisal of a situation – is highly variable between individuals, making it difficult to retrieve reliable data. The most common way to test “stress level” is to measure salivary cortisol, which has been shown to be a reliable biomarker (Bozovic et al., 2013; Hellhamer et al., 2009; Smyth et al., 2013; Trilck et al., 2005). Salivary cortisol concentration increases for approximately 20 minutes after the termination of a psychosocial stressor (Kirschbaum and Hellhammer, 2000). Thus, if students experience stress during an exam, it should be revealed in the cortisol concentration of a post-exam saliva sample. In this experiment, the association between a student’s change in confidence and change in salivary cortisol level was tested. Under normal circumstances, cortisol will spike in the morning upon wakening (known as the cortisol awakening response) and subsequently decline throughout the day. Thus, when taking two samples of salivary cortisol, the latter should have a lower concentration. As such, it is expected that, if there is no disturbance of homeostasis (e.g., psychosocial stress), cortisol levels will continue to drop throughout and following the examination. If the exam is more difficult than initially expected, this will be realized in the midst of the exam, thus activating the stress response, which should be revealed as a higher concentration of cortisol in the post-exam saliva sample than the pre-exam saliva sample. Thus, it is hypothesized that if cortisol concentration is higher after the exam, then the student should rate his or her preparedness lower after the exam than before the

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exam. Because people handle stress differently, however, the converse is not necessarily true.

Materials and Methods The Oklahoma Baptist University Human Subjects Research Committee approved the protocol for this experiment prior to the beginning of the experiment. Subjects also signed informed consent statements prior to any sample collection. In order to help control for potential confounding variables, a pre-exam questionnaire was administered before each saliva sample was taken. An example of the pre-exam questionnaire can be seen in Table 1. The wide variety of questions illustrates the difficulty of attaining a non-biased cortisol sample for indication of a stress response. Lack of sleep, food, water, certain medications, exercise, illness, and personal tragedy can all affect the circadian rhythm, or daily cycle, of cortisol. Of particular note are contraceptives. The two physiology classes from which samples were taken were predominately female. Consequently, some subjects were taking some form of oral contraceptive. Interestingly, oral contraceptives have been shown to blunt salivary cortisol levels; corticosteroid binding-globulin (CBG) binds circulating cortisol, leaving the unbound, biologically active cortisol to be measured in saliva. If CBG levels are increased, as occurs in women who use oral contraceptives, then free cortisol levels will not reflect a spike in total cortisol following a stressor (Kirschbaum et al., 1999; Kumsta et al., 2007). Accordingly, subjects who reported taking oral contraceptives, as well as those who reported taking other drugs that may affect cortisol levels, were not included in the analysis. Another disqualifying factor was 58

reporting less than three hours of sleep, as sleep deprivation is known to affect salivary cortisol levels and the response to stress (Goh et al., 2001; Lasikiewicz et al., 2008; Omisade, Buxton, & Rusak, 2010). As well as controlling for unseen variables, the pre-exam questionnaire posed the question, “How prepared do you feel for this exam? 1 being not at all, 10 being extremely prepared.” This question established the initial, or predicted, preparedness in regards to the exam the subjects were about to take. The postexam questionnaire, which can be seen in Table 2, asks a question that establishes retrospect preparedness. For example, if the test was more difficult than a subject had predicted it to be, then the subject would mark a lower number on the post-exam question than on the pre-exam question. This would indicate a loss of predictability, which is a common stimulant of psychosocial stress (Bollini et al., 2004; Koolhaas et al., 2011; Yang et al., 2011).Alternatively, an equal number (e.g., 5 and 5) or higher number on the post-exam question would indicate that the subject’s predictions matched reality. This study was conducted at Oklahoma Baptist University and included students from two physiology classes in the Fall 2013 semester. Both exams took place from 11:00 a.m. to 11:50 a.m., with one occurring on a Friday and the other on the following Monday. The original sample was n = 47. However, some subjects were disqualified based on previously established study criteria. This left an enriched n = 29. Each subject was given an identifying number, allowing for subject privacy as well as efficiency in pairing pre- and post-exam questionnaires and saliva samples.

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All subjects filled out a pre-exam questionnaire immediately preceding the exam. Following the pre-exam questionnaire, subjects were asked to chew on a cotton ball for 1 minute. They were then instructed to squeeze the saliva from the saturated cotton ball into a sterile 1.5 mL centrifuge tube. The purpose of the cotton ball was to prevent excess mucous from entering the tube along with the saliva, thus decreasing viscosity and enhancing assay results. Upon completion of the exam, subjects filled out the post-exam questionnaire and immediately produced a second saliva sample following the same protocol as the first. All samples were frozen (-30° C) immediately following collection. A ParameterTM competitive binding immunoassay from R&D systems (KGE008, Minneapolis, MN) was used to quantitatively determine salivary cortisol concentration from samples as per the manufacturer’s recommendations. Because it is a competitive binding assay, cortisol from the samples compete against horseradish peroxidase-labeled cortisol for binding to mouse monoclonal antibody. Absorbance was measured at 450nm, with correction at 540nm in a 96well microplate reader. A standard curve calculated from cortisol standards produced an R2 value of 0.99163. Cortisol concentration was derived from the standard curve line equation y = -0.196ln(x) + 0.5089, solving for x, and multiplying by five (manufacturer’s recommended sample dilution factor). Preexam measurements were compared with post exam measurements for each subject. If there was a decrease in cortisol concentration, then the subject was pooled in the “cortisol decreased” group. On the contrary, if there was an increase in cortisol, which would signify a stress response at some point during the exam, then the subject was pooled in the “cortisol increased” group. 60

Results The original hypothesis was that if a physiological stress response occurred, then the perceived difficulty of the exam was greater in retrospect than prior to the exam. This manifestation would be reflected by the post-exam saliva sample showing an increase in cortisol as well as the subject giving a lower rating on the post exam question, “Now that you have taken the exam, how prepared do you think you were?” Cortisol should naturally decrease over a period of time (with the exception of after eating a meal, which was controlled for in the pre-exam questionnaire). Thus, any increase in cortisol over a one-hour period would imply that the subject encountered a stressor. In turn, indicating that they were less prepared for the test in retrospect suggests that reality did not match their prediction, which is a potential cause of psychosocial stress. Table 3 displays the measured cortisol levels and confidence change for each subject. Association between change in confidence (difference between pre- and post-exam perceived preparedness) and change in cortisol was evaluated using a contingency table, as shown in Table 4. An increase in cortisol correlated significantly with a decrease in confidence (p = 0.0442). Holding to its natural circadian rhythm, cortisol should never increase over a period of time other than following a meal or during the cortisol awakening response in the morning. It was found that, out of the enriched sample of 29 subjects, 10 had an increase in cortisol during the exam. Of those 10, 9 indicated a decrease in confidence. These results suggest that an inaccurate perception of preparedness for an exam can cause acute stress as measured by a salivary cortisol spike. 61

Discussion Few studies have examined cortisol levels of college students. Of the studies that have been done, several have found exams to be a source of stress (Droogleever et al., 2004; Elizabeth et al., 2009; Joshi et al., 2012; Ng et al., 2003a). In some cases, exams were cited as a source of “anticipation stress” due to the increased pre-exam cortisol levels (Lacey et al., 2000; Ng et al., 2003b). However, no studies could be found that considered the association between a dissonance in preparedness prediction and cortisol levels. A loss of predictability, and thus a loss of perceived control, is a known inducer and augmenter of psychological stress via hypothalamic-pituitary-adrenal (HPA) activation (Bollini et al., 2004; Koolhaas et al., 2011; Weiss, 1970; Yang et al., 2011). Transiently, this is of no concern. However, chronic stress has been strongly linked to a plethora of ailments, including lack of sleep, poor diet, impaired working memory, hypertension, heart disease, and diabetes (Drake et al., 2004; Kalimo et al., 2000; McEwen et al., 2010; Miller et al., 2011; Oei et al., 2012; Sapolsky 2004; Shoofs et al., 2008). When students have several exams in a short period of time, they could be accruing acute stress to the point of chronic stress, which in turn perpetuates itself through the mechanisms just described. Onyenekwe et al. (2014) also expressed concerns of acute stress in college progressing into chronic stress. Of specific note to colleges should be the lack of sleep and impaired working memory. Chronic stress and lack of sleep are locked into a viciously perpetuating cycle. In turn, both vitiate memory consolidation (Idzikowski, 1984). 62

New knowledge on psychosocial stress may stimulate further research into the structure of college examinations. It is not suggested that testing should be discarded. However, perhaps testing usage and protocol should be reexamined in light of new research in the fields of psychology, neuroscience, and endocrinology. Studies involving human psychological states and hormones can be exceptionally difficult to conduct. Even with precautions, unforeseen variables or inaccurate recordings can influence results. Future studies should seek out factors that influence differences in circulating levels of CBG, as can be seen with oral contraceptives. Further studies on the dynamics of CBG will help elucidate its role in stress and measurement of salivary cortisol. Future studies should also measure salivary cortisol levels the week prior to the exam in order to gain a better understanding of each individual’s fluctuations. Similar studies would also benefit from increased sample numbers. It would be interesting to determine if the results of the present study are consistent at larger universities with larger class sizes. Ultimately, more research needs to be performed involving college students and stress levels. College is a major life change for many students, and can introduce an array of stressful situations. More knowledge and a better understanding of the forces at work in stress, such as hormone fluctuations, effect on memory and learning, and effective coping strategies, would benefit the educational system and allow for a better learning experience for the college student.

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Table 1. Assigned Number: How closely did the difficulty of the exam match your predicted difficulty? 1 being not at all, 5 being extremely

Now that you have taken the exam, how prepared do you think you were? 1 being not at all, 10 being extremely prepared.

Table 2. Assigned Number

Age

Classification

What time did you wake up today?

How many hours of sleep did you get last night?

Have you eaten in the past hour?

Have you had anything to drink in the past hour? If so, what?

At what time, if applicable, did you exercise today?

What vitamins or medication have you taken in the past 24 hours and when did you take them?

Have you experienced a personal tragedy in the past week (ex: family death, divorce, etc.)?

Are you currently experiencing or have you experienced illness in the past 3 days?

How prepared do you feel for this exam? 1 being not at all, 10 being extremely prepared.

Table 3.

Sample 1 2 3

Pre-exam Cortisol (ng/mL) 2.682 1.669 4.490

Post-Exam Cortisol (ng/mL) 1.439 6.160 4.822

Δ Cortisol (ng/mL) -1.243 4.492 0.332

Δ Confidence (1-10 scale) 1 -4 -3

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4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

3.560 1.779 2.078 8.324 1.409 3.843 1.343 1.135 2.325 4.117 3.680 4.749 1.734 3.323 2.465 1.135 4.749 3.174 3.833 2.844 1.752 3.488 1.189 1.995 4.117 1.020

2.628 1.673 2.581 7.870 0.935 1.488 1.792 0.678 2.568 2.062 2.484 0.994 1.354 9.078 2.057 1.213 3.736 3.340 4.822 2.416 1.112 1.109 1.499 1.690 3.247 0.959

-0.932 -0.106 0.503 -0.454 -0.474 -2.355 0.449 -0.457 0.243 -2.055 -1.195 -3.755 -0.380 5.755 -0.409 0.078 -1.013 0.166 0.989 -0.428 -0.639 -2.378 0.311 -0.305 -0.870 -0.061

1 2 0 0 0 -1 -4 -1 -4 1 -4 0 0 -2 0 -2 -2 -2 -1 -2 -3 -1 -1 -5 -3 -1

Table 4. Cortisol increased

Cortisol decreased

Totals

Confidence increased/no change

1

9

10

Confidence decreased

9

10

19

Totals

10

19

29

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“The greatest weapon against stress is our ability to choose one thought over another.” – William James

CHAPTER 5 CONCLUSIONS Now What? The problem of stress has been unfolding over the past four chapters, and, hopefully, some light was shed on this convoluted aspect of human life. Stress remains an inevitable – and necessary – part of living. Though the discussion thus far has been a bit disconcerting, the outlook is not completely dismal. Humankind has a way of fixing issues once their inner workings have been elucidated. The same enhanced cognition and social capabilities that allow psychosocial stress to arise also permit humans to unravel the mystery of stress and rise above its grip on life. Human intelligence and ingenuity has proven to overcome impediments time and time again through advances in medicine and technology. If smallpox can be wiped off the face of the earth, then perhaps humanity can find a way to get a hold on stress.

The Love Hormone Chapter three contained a discussion about coping strategies, one of which was social support. Being the social creatures that human beings are, it seems intuitive that sociality would be essential to overall psychological and

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physical health. Studies have shown the overall buffering affect that social support exerts on stress (Giesbrecht et al 2013; Schwarzer, Bowler, and Cone 2014). As it turns out, when it comes to stress, social support retains a biological basis in a hormone called oxytocin, also known as the love hormone. Oxytocin demonstrates importance in everything from mother-child bonding to social memory to sexual attraction and trust (Lee et al. 2009, 127). Interestingly enough, it also has a lot to do with stress. It seems as though the stress response could be attenuated if there existed some way to blunt HPA activation. Fortunately, Mother Nature has provided this attenuation in the seemingly multifaceted hormone, oxytocin. Studies have shown that oxytocin release will actually buffer the HPA axis activation and result in lower cortisol levels (Neumann et al. 2000; Legros 2001; Linnen et al. 2012). Even better, oxytocin seems to exhibit a sort of sociobiological positive feedback. There is a reason feeling stressed makes people want to seek out a compassionate friend or loved one – oxytocin. Social defeat is a common way for an animal (or human, for that matter) to become stressed and exhibit social avoidance. Take a socially defeated rat, inject him with oxytocin, and suddenly he becomes very social (Lukas et al. 2011). What does this mean? Well, if you are feeling stressed, oxytocin is released and stimulates you to be social. Being social involves physical contact and talking, both of which have been shown to release more oxytocin, lower cortisol levels, and actually make people feel better (Heinrichs et al. 2003; Seltzer, Ziegler, and Pollak 2010). For once in this conversation on stress, a

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vicious cycle that is good! Perhaps Mother Nature has a better handle on things than she is given credit.

Pick a Hierarchy As social creatures, seeking out and exploiting our sociality is a great way of naturally augmenting the stress buffering effects of oxytocin. Exploiting sociality does not always mean engaging in a deep and serious conversation about how things are going. As stated in chapter three, humans are instinctively hierarchical creatures. But what exactly is the “human hierarchy?” Fortunately, the SES hierarchy does not have to be the only, or even the most important, hierarchy. Humans have the unprecedented capability of belonging to multiple hierarchies. Even more remarkable, is the ability to place importance on particular hierarchies at will. Obviously certain hierarchies, namely the SES hierarchy, maintain a more overt presence than others. However, this does not prevent people from mentally escaping from one ill-fated reality and instilling significance in another. This sounds like a mind trick or some sort of pseudoscience, but people accomplish this escape all the time. One everyday example would be the mental escape that is experienced when reading a good novel or watching a good movie. Reality seems to dissipate and all that matters is what is going on in this alternative reality. This is similar to what happens in alternate human hierarchies. When you are out coaching the little league team, your job that you despise is not of importance. In what you place importance does not matter. All that matters is that you find something in which to place it. Whether it is in a career, avocation, hobby, sport, reading, or whatever, the important thing is that you find 68

solace, a sense of belonging, and maybe even a little authority. The position in the hierarchy may matter, but which hierarchy does not.

Remember the Basics Ultimately, the stress response is a physiological reaction. The body remains brilliantly adapted to coping with and overcoming acute physical stressors. The problem only arises when the stressor is chronic and/or psychological. It has also been emphasized that stress does not cause disease but rather promotes and exacerbates it. The best way to stay healthy, and not give stress something to work with, is to exercise. Thinking back on the whole purpose of the physiological changes (increased heart rate and respiration, mobilization of glucose, diversion of blood to larger muscles, etc.), it makes perfect sense why exercise would be a great way to alleviate stress. Exercise gives the natural outlet for the changes that occur when one is stressed. Moreover, exercise need not be the “continue until you puke” kind of workout in order to support stress relief. In fact, even low intensity exercise has been shown to reduce circulating cortisol levels (Hill et al. 2008). The more of a habit exercise becomes, the more beneficial influence it will have on the HPA axis. Long-term exercise can actually blunt stress responses to novel situations and decrease the amount of CRF created, thus decreasing cortisol levels (Droste et al. 2003). Remember, CRHàATCHàCortisol.

Find the Inner Zen

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Assuming exercise is not ideal, there are still other ways of relieving stress. Meditation has been found to be an effective way to tune down the HPA axis and relieve stress (Sudsuang, Chentanez, and Veluvan 1991; Oman et al. 2008). Though the effects seem to be temporary, meditation seems to be a great way to cope after a stressful day at work. Hundreds of spiritual and mind-opening techniques, from mediation to prayer, exist that hold the possibility of eliciting some sort of effect on stress. However, the evidence remains rather week as of now, and more studies need to be done in order to confirm their effects. The great thing about coping mechanisms such as spirituality and exercise is that they offer the social opportunities, which further combats psychosocial stress. Start practicing your aerobics or meditation now, and in a few short weeks you could be teaching a class at the local YMCA. This provides the alternative hierarchy in which you perform some stress-relieving practice, and you are important within that particular hierarchy. On top of that, you are helping others combat the stress in their lives, creating rapport with the community, and doing your small part in cultivating social capital.

Concluding Remarks It cannot be overstated how incredibly complex and enigmatic the stress response is. Fundamentally multi-dimensional and convoluted, it simply cannot be completely unraveled in a single piece of work. However, this thesis has provided a well-established introduction to the topic of stress, its physiological functioning, social and psychological implications, and a few notes of hopefulness when it comes to dealing with life stressors. 70

It is important that stress is not seen as some sort of enemy or intrinsically “bad” aspect of human life. It is a trait that is, and has been, essential to human survival and adaptation. The problems that arise in stress are unique to socially complex species, and are exceedingly present in modern Western society. Seeing stress for what it really is remains key to overcoming and living with it; stress is not something to be dismissed, and true coping comes with understanding how and why the body acts the way it does. Once something is acknowledged and understood, it appears less frightful, less unnerving, less… stressful.

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