According to prominent neuropsychologist Robert Sapolsky, “for every step down the socioeconomic status ladder, starting from the top, average health worsens” (Sapolsky, 2017). Why is this? The answer, surprisingly, has a lot more to do with us than with anyone else or some greater systemic conspiracy. Sapolsky insists that it’s not about being poor, but rather feeling poor, that gets us; the constant stressors associated with perceived financial instability are what cause immutable damage. Ichiro Kawachi, a graduate professor at the Harvard T.H. Chan School of Public Health, agrees that this chronic activation of the stress response is not maintainable. So, the question is, how does this work? How is stress tied in to physical health, and what can be done?
The first step to solving this conundrum lies within realizing the extensive communication that occurs between our brain and our immune system, involving a multitude of cells, mediators, and channels from both sides (Ashley & Demas, 2017). The functioning of one system inevitably impacts the other; everything is connected. Proof of this link is best seen when things start to go wrong. Immune dysfunction has been shown to lead to problems in the central nervous system, such as diseases like “stress, behavioral or mood disorders, brain injuries, mental disorders, tumors, stroke, Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD), Tourette syndrome (TS) and multiple sclerosis (MS)” (Ashraf et al., 2018). On the other hand, those with major psychological disorders generally exhibit signs of immune deregulation, which may ensue “autoimmune diseases, diabetes, and atherosclerosis” (Ashraf et al., 2018). So, what’s the functional significance of this?
Well, these findings tell us that stress is extremely closely correlated to immune function. Dysfunction of the immune system may lead to stress, and conversely, too much stress may lead to immune dysfunction. In such cases, it is important to differentiate between types of stress. This leads us to discuss two important distinctions.
Acute stress, which activates whenever we’re in a situation that gets our adrenaline pumping and our blood flowing, leads to a temporary increase in pathogen-fighting NK immune cells, preparing our bodies for fight-or flight-situations. It is only once this stress builds up without allowing our bodies to relax that it becomes dangerous.
This is clear in cases of the second kind of stress–chronic stress–in which the prolonged activation of the sympathetic nervous system suppresses the immune system, sometimes to the point that it is unable to adapt. Without ample rest and recovery, the same pathogen-fighting cells may tire and reduce in effectiveness. This recurring stress may also affect a much wider range of immune activity, including immune response to vaccinations and activation of latent viruses such as herpes simplex virus, etc. (Ashraf et al., 2018).
Thus, emotions/mood states have a direct impact on immune function. A clinical level of psychological stress or anxiety seems to suppress the immune system by raising catecholamine and CD8+ T cell levels, which increases the risk of viral infection (Ashrad et al., 2018). Additionally, stress can lead to severe worsening of asthma by the release of histamines, and an increase in risk for diabetes by altering insulin needs. It also alters acid concentration on the stomach, possibly leading to ulcers, and can contribute to plaque build-up in the arteries (Ashrad et al., 2018). Long story short: stress will not only hurt you mentally, but physically, as well.
The flip side of this largely distressing information is that just as there is a lot of evidence that states stress will harm you, there is also an abundance of research that assures that positive mood states will boost your health. It is generally accepted that optimistic people are less likely to have immune disorders than pessimistic people; “optimism may be conceptualized as a buffer against stress related changes in the immune system” (Ashraf et al., 5).
So, what are the takeaways from this? To reference the original prompt: neuroimmunopsychologists are not any closer to relieving the pressure on those less economically fortunate; tackling the financial crisis is no easy task. However, these findings indicate that at least a portion of the struggle may be resolved from within our own minds. By increasing awareness of how important positive mental states are, more investment into mental health may be researched and implemented, and even sought out in normal, everyday life.
Ashley, N. T., & Demas, G. E. (2017). Neuroendocrine-immune circuits, phenotypes, and interactions. Hormones and behavior, 87, 25-34.
Ashraf, G. M., Azhar, A., Zia, Q., Ali, A., Rehan, M., Owais, M., … & Rajeh, N. (2018). Relationship between CNS and Immunology: Correlation with Psychology. Current drug metabolism, 19(10), 847-855.
Sapolsky, R. M. (2017). Behave: The biology of humans at our best and worst. Penguin.