On Stress-Part One-Sapolsky
Posted by dlende on December 19, 2007
In my research in Colombia, I dealt with teenagers across the spectrum—kids from good families with futures they could see, kids who had gone through more shit than most people will see in their lifetimes. One kid, let’s call him Rafa, came from a small town outside of Bogotá, his family not in the best circumstances. In my talking with Rafa, he dwelled on the horrible process of social exclusion that he went through—first the whispers and bad looks, then problems at school, the violence and rejection at home, and the final demand from a coalition of men, powerful and dangerous men, that he simply leave. Sure, Rafa was no saint himself, but that’s not the point. The dwelling on what other people did, that was the hard thing in his life when I met him. He didn’t deal with that in the best way either, finding support in hate-filled ideologies and drug-using friends. I don’t think many adults had ever just taken the time to talk with him, to get to know him. And he still got kicked out of the school, a school that took in kids that had had problems elsewhere, during that year I knew him. I remember that administrative meeting well. No teacher spoke up for Rafa, and I didn’t count as the anthropologist. So Rafa ran out of chances once again. Except that is the wrong expression—he ran into chances that bopped him around like the ball on a roulette wheel, only to end up on zero. It was people that did that.
So that’s the ethnographic moment.
Let’s turn to some other research. Robert Sapolsky’s work is widely known. His best-selling book, Why Zebras Don’t Get Ulcers, is now in its third edition, and his Perspectives piece in Science has been cited 485 times according to Google Scholar. He is acclaimed in biological anthropology circles because of his concern with mechanism, the elegance of his naturalistic studies with baboons in Kenya, and his consideration of the heavy stress-related costs of inequality. The back cover of the Zebras book summarizes the core argument of the book, “When we worry or experience stress, our body turns on the same physiological responses that an animal does, but we usually do not turn off the stress-response in the same way—through fighting, fleeing, or other quick actions. Over time, this chronic activation of the stress-response can make us literally sick.”
Michael Blakey is better known for his critical archaeology work and his leadership with the New York African Burial Ground. The work I will discuss, Blakey’s chapter “Beyond European Enlightenment” in the edited volume Building a New Biocultural Synthesis, has been cited 5 times according to Google Scholar. His earlier chapter “Psychophysiological Stress as an Indicator of Disorder in Industrial Society” in the book Diagnosing America: Anthropology and Public Engagement has been cited all of once. But it is Blakey’s work that has turned my mind around in the past few days in ways that Sapolsky never quite has. These two posts will explore why the blurb on Sapolsky’s book is wrong and why that is important to what neuroanthropology can do.
Today I will start with Sapolsky’s recent Science review “The Influence of Social Hierarchy on Primate Health.” The article begins with the familiar “socioeconomic gradient,” where the “stepwise descent in socioeconomic status (SES) predicts increased risks of cardiovascular, respiratory, rheumatoid, and psychiatric diseases; low birth weight; infant mortality; and mortality from all causes.” Sapolsky then provides a traditional review of the stress response—there are physical and psychosocial stressors, and both activate an “array of endocrine and neural adaptations.” These adaptations are generally mobilized in response to challenges to homeostasis. In response to “an acute physical challenge,” the stress response works through mobilizing energy, increasing cardiovascular tone, and inhibiting unessential anabolism; in other words, the classic “fight-or-flight” framing of stress. Chronic activation, particular by chronic psychosocial stressors, can increase or worsen health problems ranging from “hypertension, atherosclerosis, insulin-resistant diabetes, immune suppression, reproductive impairments, and affective disorders.”
Sapolsky then reviews the animal literature on hierarchy, ranks, and stress. His summary of this body of work is quite illuminating, and shows his fine mind at work. It will also prove important to my discussion tomorrow, so here is the excerpt is in all its glory:
“Thus, under a variety of circumstances, social dominance can be associated with the most stress-related pathology, whereas in other situations, this is a trait of subordinate individuals. Are there common themes underlying this variability? Broadly and logically, adverse physiological profiles are most pronounced among animals of the rank exposed to the most physical and psychological stressors. This can arise from (i) low degrees of social control and predictability (as in dominant animals in unstable hierarchies and subordinate animals in small living spaces); (ii) a paucity of outlets after exposure to stressors (such as subordinate individuals in species lacking alternative strategies to hierarchical competition); (iii) a paucity of social support (for example, subordinate animals in settings with few kin and little access to social grooming); or (iv) high rates of physical stressors (such as dominant individuals who, as a function of their species or the instability of their hierarchy, must constantly reassert their dominance by physical means). Moreover, these links between rank and pathology can be made even more dramatic by the culture of a particular social group and by a personality prone toward interpreting ambiguous social circumstances as psychologically stressful (650).”
Sapolsky then makes a particularly important point, “We know that a particular rank gives rise to a particular physiological profile, rather than vice versa (651)” based on studies that show that physiological profiles of individually housed animals in no way predict their subsequent ranks when placed in groups. This important point, that social structures can drive our physiology and the implications this might have for social theory, is not dwelled upon. Rather, Sapolsky proceeds to document in detail the “stress-related physiological endpoints” that can result from ranking. These endpoints include: hyperactivity of the glucocorticoid system, secretion of catecholamine hormones, adverse cardiovascular function, suppressed reproductive function, compromised immune function, and altered neurobiology. For the neurobiology, the cascade of effects includes “inhibition of neurogenesis, dendritic atrophy, and impairment of synaptic plasticity (652)” (in other words, less agile brains over the life course) and alterations in the “neurochemistry of anxiety” that appear to reflect the “demands on anxious vigilance,” at least among feral baboons.
Sapolsky opens his discussion section by considering the relevance of this research to humans. He notes that humans do not occupy linear hierarchies—we belong to multiple hierarchies reflecting our multiple social roles (a church deacon and low-prestige employee). We also have internal standards, which “makes humans less subject to the psychological consequences of rank.” (Though see work by William Dressler and Clarence Gravlee which tell us more about how our standards affect stress.) Nevertheless, he points out that for humans the SES gradient in health as “a robust example of social inequalities predicting patterns of disease (652).” He notes that the gradient is not due to limited access to health care (the gradient appears in countries even with universal health care) and that “only a small portion of the SES-health relationship” is explained by “SES-related life-style differences,” such as the higher rates of smoking, less healthy diets, and more sedentary lifestyles seen in some lower SES communities. Rather, he points to evidence that suggests that “the gradient arises from psychosocial factors,” including “feeling poor” (rather than objective SES) due to the effect of one’s surroundings and decreases in “social capital,” where income inequality is linked to decreased levels of local trust and increased sense of alienation and disenfranchisement.
He concludes, “Strong associations between social status and health thus occur in numerous species, including humans, with the poor health of those in the ‘wrong’ rank related to their surfeit of physical and psychosocial stressors (652).” (By the way, surfeit means “an excessive amount”—I had to check that one out.) He further notes that the nonhuman literature highlights “the variability, qualifiers and nuances of the health-rank relationship,” whereas in humans “there is a robust imperviousness of SES-health associations to differences in social and economic systems (652).” This point does not mean that we are less complex socially than baboons. Rather, “it is a testimony to the power of humans, after inventing material technology and the unequal distribution of spoils, to corrosively subordinate its have-nots (652).” In other words, our socioeconomic systems and the way people interact in those systems make the “wrong” status people pay. And they pay with their health, among other things.
To sum up, rather than a culture of poverty, which led to blaming impoverished people for their own ways of coping, we have a biology of poverty and a cultural system of exclusion. The system itself is something that we humans have created, and which feeds back onto us. At the same time, the people with power in that system make the rest of us pay. Thus, Rafa was literally excluded by others, but he also dwelled on the implications of his systemic exclusion while the teachers felt it perfectly appropriate to not offer Rafa another chance to enroll because he did not meet the minimal requirements of the school (e.g., failing in most subjects, disciplinary problems). The Sapolsky approach, supplemented by some of the other people mentioned in this piece (Leatherman, Dressler, Gravlee), makes a nice explanation. It also offers a good research agenda, which is also important. However, it rests too strongly on an essentialized notion of physiological stress as animalistic and psychosocial stress as something located in the mind. Thus, it relies on a mind/body distinction that does not capture what Rafa spent a good amount of time explaining to me—the dwelling on his exclusion, and his entry into other relationships and ideologies to deal with his present “wrong” states. Can these too be part of the fight-or-flight response? Or is fight-or-flight the problem? Check in with the next post.