By: Talia Simpson
As finals loom on the horizon, stress levels tend to rise as we attempt to cram all our studying and assignments into a limited allotment of time. We know that prolonged stress can cause us to feel physically run down, but how does this mechanism work? Why do emotional states impact our physical health?
The answer lies in the field of psychoneuroimmunology. Although it sounds like a mouthful, when it is broken up into three words it is actually pretty simple- “psycho” as in the workings of the mind, “neuro” as in the workings of the nervous system, and “immunology” as in the workings of the immune system. Psychoneuroimmunology, as its name suggests, studies the psychological and neurological influences on our immune systems and how these three systems, along with the endocrine system, interact with one another.
The brain is in constant communication with the immune system through two main pathways, each going in a different direction. The first is through autonomic nerve fibers, specifically noradrenergic sympathetic postganglionic axons, which go from the brain to the spleen and thymus to increase immune cells and the production of antibodies. The second is the opposite way- circulating cytokines from the immune system are monitored by neurons in the hypothalamus and cerebral ventricles, as well as by peripheral axons of the vagus nerve, and when these neurons sense too many cytokines they trigger certain brainstem neurons with axons at the vagus nerve to release acetylcholine which in turn inhibits the immune cells from releasing more cytokines.
Since the brain and the immune system are connected, it follows that mental states can influence our immune function. In fact, numerous studies have demonstrated this. One study conducted showed that when exposed to a virus that causes the common cold, people who were happy socially were less likely to actually become infected in comparison to those who were unhappy socially. In another study, it was found that people who experienced more positive emotions were more likely to have an increased level of antibody production in response to being vaccinated against the flu.
In terms of stress due to exams specifically, there is evidence that found that during exam season/a time period of stress, immune cells and cytokine levels decrease. Another study took this a step further and showed that in comparison to during the summer, small wounds took 40% longer to heal during exam season, with the immunological response declining by as much as 68%.
This is all to say that stress really matters in terms of our health. It is extremely important that we take the time, especially during finals, to nurture ourselves in ways that relieve stress- whether it be by exercising, hanging out with friends, or just doing things that spark joy.
Wishing everyone a healthy and successful finals season!