What is all this stress doing to me?
Stress is a term that is now ingrained within our society and commonly used in our day to day lives. But how does stress really affect our physical and mental health?
What happens in the body?
Selye (1936, 1950) found that on a physiological level, the body has a non-specific, generalised response to stressors that activates both the Autonomic Nervous System (ANS) and the Endocrine system. This response pattern is summarised into three stages known as Generalised Adaptive Syndrome (GAS) and can be split into acute and chronic stress responses.
For acute stressors, the first stage is alarm. The hypothalamus detects a stressor, activates the ANS, which in turn sends signals to activate the sympathetic nervous system (SNS) and adrenal medulla. The adrenal medulla releases the endocrine hormones: adrenaline and noradrenaline that facilitate the activity of the SNS. Combined, these systems prepare the body for a fight-or-flight response by increasing heart rate, blood pressure, blood glucose, and reducing resources to non-emergency body processes i.e. digestion.
Second is the resistance stage at which the body uses reserves to counteract this physiological imbalance to restore homeostasis. However, if the stressor is continuous the body will eventually be depleted of reserves and progresses to the exhaustion stage.
The response to chronic stressors is known as the hypothalamic-pituitary-adrenal axis (HPA). During this response, the hypothalamus releases Corticotropin-releasing hormone (CRH), which activates the anterior pituitary to secrete Adrenocorticotropic hormone (ATCH). ATCH stimulates the adrenal cortex to release of mineralocorticoids and glucocorticoids i.e. cortisol. This response pathway continually raises blood volume, blood pressure, and blood glucose levels as well as inhibiting inflammatory and immune response leading to illnesses such as diabetes, vascular disease, or reproductive conditions.
The constant activation of the HPA axis can also cause atrophy to and compromise the functions of parts of the brain with the greatest number of glucocorticoid receptors such as the limbic system and prefrontal cortex (Webster et al., 2002). These areas of the brain control reward pathways and cognitive processes including decision making, emotional responses, as well as serotonin (‘feel good’ neurotransmitter) efficacy (Arnsten, 2009).
Individual responses to stressors may vary significantly (Sapolsky, 1994), thus for this report, common behavioural responses and prominent psychological conditions will be considered.
Common behavioural and cognitive responses may include: disrupted sleep patterns, diminished energy, impaired cognitive abilities, withdrawal from social interactions and situations, agitated behaviours e.g. nail biting, teeth grinding, fiddling with hair/fingers and short temper or irritability, (Bressert, 2016). These can be present in responses to both acute and chronic stressors but when the symptoms persist for more than 6 months, support and professional help should be considered.
When stress is chronic or traumatic, psychological conditions can develop such as depression, anxiety and post traumatic stress disorder.
There is extensive literature on an array of both positive and negative coping mechanisms for stress (Eisenberg, 1997; Roth, 1986; Folkman & Moskowitz, 2000). For example, as reward pathways are compromised during the stress response, some people use other means to feel pleasure such as alcohol, drugs and food, which can result in negative consequences (Kreek & Koob, 1996; Ouimette & Brown, 2003).
However, there are also positive coping mechanisms. Particularly beneficial for psychological responses such as depression, many find meditation and optimism promoting therapies e.g. Cognitive Behavioural Therapy, effective (Epel et al., 2009; NHS, 2016).
Physical exercise and yoga are also effective as exercise is not only beneficial psychologically, but has a positive impact on a physiological level (Salmon, 2001). Many turn to complementary therapies such as Reflexology and Massage to combat the symptoms of and imbalances caused by stress. Further, social support is highly regarded when trying to cope as humans are social animals and to connect with others (Sapolsky, 1994).
In conclusion, we have looked at the basic physiological response pathways and the difference between chronic and acute stress on the body. It is useful to understand what happens to the body during a stressful situation, and to be able to recognise behaviours that could be signs of stress.