Chronic Stress and Depression

    Whether it was an upcoming assignment, a deadline at work, or moving to a new home, everyone has felt stress in their life. But what are the biological mechanisms behind stress? Why do we feel stress? And most importantly, how does the way we cope with stress effect our well-being?

    In a news article entitled "Researchers get to the roots of chronic stress and depression" James Kingsland explains that our stress response was formed as a survival tactic to keep out ancestors safe from others. Some of the biological effects stress has on our body is the release of adrenaline, noradrenaline, and cortisol. These hormones equipped our ancestors with a rush of energy preparing them to fight or flee perceived danger. Nowadays we are not frequently subjected to such dangers and a more common stressful event may be something like a psychosocial stressor. For example, say you were a participant in an experiment and while you were completing a mental mathematical challenge that was designed to make you fail, an experimenter entered and asked you a series of demeaning questions like "do you have experience with math"? or "did you understand the instructions of the task"? Which is exactly what Weinberg et. al. in the article "Risk and Resilience in an Acute Stress Paradigm: Evidence From Salivary Cortisol and Time-Frequency Analysis of the Reward Positivity" did. They collected Saliva samples from a control group and an experimental group (those subjected to the psychosocial stress) while participants completed tasks on the computer.

    From their data, Weinberg et. al. found evidence that intense stress can diminish the neural responses humans have to reward. This finding suggests that stress may lead to mental illnesses like depression. One key feature of depression is anhedonia, the inability to feel pleasure. Which, if your reward system is diminished by chronic stress, will likely lead to anhedonia and, later on, depression. This finding, that chronic stress leads to depression, is replicated in the research that Kingsland writes about. Researchers from the Karolinska Institutet in Stockholm, Sweden found that healthy brains in mice were able to moderate stress responses after the threat passed, but unhealthy mice brains in mice were able to moderate stress responses after the threat passed, but unhealthy mice brains had a more acute response to a stressful situation and took longer to return to normal. The healthy brains had a normal amount of p11, a protein found in the brain that is believed to have an enhancing effect on the neurotransmitter serotonin, a mood regulator and is believed to play a role in depression when levels are low. So, the way we cope with stress may affect our ability to stay free from mental illness and, unfortunately, it may be out of our control due to genetic factors effecting our p11 levels or our neural reward system.

WORKS CITED

Kingsland, James. "Researcher Get to the Roots of Chronic Stress and Depression." Medical News Today, MediLexicon International, 13 Oct. 2020, www.medicalnewstoday.com/articles/researchers-get-to-the-roots-of-chronic-stress-and-depression.

Weinberg, Anna, et al. "Rist and Resilience in an Acute Stress Paradigm: Evidence From Salivary Cortisol and Time-Frequency Analysis of the Reward Positivity." Association for Psychological Science, 16 Jan. 2020, pp. 1-13., doi:10.1177