People often talk about stress and feeling stressed out. The combination of multiple work, family, and other commitments can start to feel like they’re crushing us.
So what exactly is stress? It occurs when strain is placed on the body in a way that disrupts its normal balance and functioning. The source can be internal or external, and it can be exerted psychologically or physiologically.
Effects of stress
Stressors can range from major life events to low-level stressors that are present in the background on an ongoing basis. Sometimes stress is a good thing; when you’re facing a hungry lion, you don’t want to be relaxed. However, when stress is unremitting, it can do some serious damage.
When it comes to memory, there’s sort of a Goldilocks effect with stress; some stress can improve memory function, whereas too much stress impairs memory. During stressful events, the brain is more likely to remember details that would help to avoid putting us in the same sort of situation again.
The effects of intense and prolonged stress are particularly significant in children. Exposure to abuse and conflict can disrupt the ability to regulate emotions and develop healthy attachments and intimacy. Learning difficulties and poor school performance may result, and there may be increased antisocial behaviour, depression, and anxiety.
Stressors in the form of loss, humiliation, or danger can increase the risk of depression and anxiety disorders. The cumulative effect of different kinds of stress can produce a synergistic increase in the risk of mental disorders (sort of a 1+1=3).
Part of the initial response to stress comes from the activation of the sympathetic nervous system, i.e. the fight or flight response. This involves the release of the hormones epinephrine and norepinephrine.
The hypothalamic-pituitary-adrenal (HPA) axis is another pathway used by the brain to initiate the stress response. The hypothalamus, which acts as a control centre, can be triggered by the amygdala. The hypothalamus then sends a signal to the pituitary gland to release ACTH (adrenocorticotropic hormone), which then stimulates the adrenal glands to release the hormone cortisol. In the short term, cortisol prepares your body to respond to the stressor, but longer-term dysregulation of the HPA axis can have a negative effect.
In the short term, stress boosts energy levels and sharpens your senses. Stored sugar in the form of glycogen is released from the liver to fuel your reaction to the stressor. Your heart is pumping, and your airways expand to bring in maximum oxygen. Energy is diverted away from resting functions like digestion and reproductive system function. The hormone rush causes your memory to focus on stressor-related input, leaving less capacity to encode non-stress-related information into memory.
Chronic stress can contribute to or worsen a number of health conditions, and can keep the HPA axis persistently hyperactivated. Changes in heart rate and blood pressure can occur, and there is an increased risk for heart disease and diabetes. As the body becomes exhausted by the ongoing stress response, the immune system weakens.
The gastrointestinal system can be affected, which can be particularly problematic for people with irritable bowel system (IBS) or inflammatory bowel disease (like Crohn’s and ulcerative colitis). Depression and some other mental illnesses appear to have a link to inflammation, although the nature of that link is still being explored.
Reacting to stressors: NUTS
There are four aspects of a stressor that result in the release of stress hormones:
- Threat to the ego
- Sense of control
The acronym for this is, suitably enough, NUTS. The novelty and unpredictability seem obvious enough, but the threats to the ego and sense of control dig a little deeper. For me, lack of control is huge. Not that I’m necessarily a controlling person, but having no control sends me cowering into my cave.
Chronic mental illness stops being novel pretty quickly, but it starts to develop a predictable unpredictability Threat to the ego? Check. Loss of control? Double check.
The ability to manage stress can be influenced by both personal and environmental factors. High levels of the personality traits of neuroticism and emotionality can make it more difficult to handle stress. Strong social supports can improve the ability to respond to stress. A study by Wofford found that negative mood patterns, anger/irritability, and low self-esteem tend to increase the physiological response to stress.
A study by Crum and colleagues found that attitudes toward stress influence its emotional and cognitive impacts. Participants who viewed stress as a challenge that could help them grow displayed greater cognitive flexibility than those who viewed stress as a threat.
There’s also a difference between eustress and distress. Eustress is adaptive and helps us to function better. Distress is persistent and does not respond to coping strategies. And what would the opposite of stress be? While relaxation might seem like the obvious answer, resilience is actually more fitting.
Holmes & Rahe Stress Scale
Two psychiatrists developed the Holmes and Rahe Stress Scale, which assigns a score to various different potential stressors (it can be found on Wikipedia). On the high end, the death of a spouse was associated with 100 “life change units.” Marriage was assigned a score of 50, while personal illness/injury was only 3 points higher. Death of a close friend is supposedly easier to adjust to than gaining a new family member, and both are less stressful than marriage. I’ve got to say, I’m not particularly impressed with this scale.
What I find fascinating is what a great example that stress reactions are of the interconnectedness between mind and body.
How does stress affect you?
You can find the rest of the what is… series in the Psychology Corner.
- American Psychological Association
- Centre for Studies on Human Stress: Stress Hormones and Memory | Stressors
- Crum, A.J. (2017). The role of stress mindset in shaping cognitive, emotional, and physiological responses to challenging and threatening stress. Anxiety, Stress, & Coping.
- Harvard Health Publishing
- Schneiderman, N., et al. (2005). Stress and health: Psychological, behavioral, and biological determinants. Current Reviews in Clinical Psychology, 2005(1), 607-628.
- Wikipedia: Psychological stress | Stress (biology)
- Wofford, J.C. (2001). Cognitive–Affective Stress Response: Effects of Individual Stress Propensity on Physiological and Psychological Indicators of Strain. Psychological Reports.
The COVID-19/Mental Health Coping Toolkit page has a broad collection of resources to support mental health and well-being.