# 10 - 9. Stress physiological and psychological asp

# 9. Stress: physiological and psychological aspects

© SPMM Course 
9. Stress: physiological and psychological aspects 
 
Stress is an organism’s response to a challenge in the environment or stimulus. The response, deemed 
fight-or-flight, is via the activation of the sympathetic nervous system. Though the sympathetic nervous 
system activation is short-lived (as the parasympathetic system calms down the physiological response), 
prolonged stress can have systemic effects (e.g. cardiac dysfunction). 
The neuroendocrine system plays an important role in regulating response to stress. (see the chapter on 
Neuroscience for further details.) 
In psychological terms, stress is the feeling of pressure – positive stress or ‘eustress’ is a small amount of 
stress that improves motivation and ability but large amounts of negative stress (‘distress’) can be 
detrimental to mental health. As well as the external environment, stress can also be caused by internal 
cognitions, which can be addressed in CBT for anxiety. 
Stress can be classified into four categories: 
Crises/catastrophes 
Completely out of the control of the individual e.g. natural disasters, war – can 
lead to post-traumatic stress disorder 
Major life events 
Going to university, marriage, birth of a child, the death of a loved one (NB not 
all life events produce detrimental stress; the context of occurrence is important). 
Daily hassles or 
microstressors 
Meeting deadlines, making decisions, irritating colleagues. 
Ambient stressors 
Low-grade environmental e.g. pollution, traffic, noise 
 
 
Stressors can result in various levels of conflicts. 
 Approach-approach conflict: choosing between two equally attractive options e.g. which restaurant to 
have dinner 
 Avoidance-avoidance: choose between two unattractive options 
 Approach-avoidance conflict – attractive and unattractive traits e.g. going to university but incurring 
significant debt 
Stress Vulnerability model (Zubin and Spring, 1977) proposes individuals have strengths and 
vulnerabilities for dealing with stress. On the diagram shown here, person a has low vulnerability and 
thus can deal with a high deal of stress without much negative consequences, whereas person c has high 
vulnerability and therefore even moderately low stress can cause them to become mentally unwell. This 
model applies to a wide variety of psychiatric disorders including psychosis. Causes of increasing 
vulnerability include genetic factors, childhood loss and trauma. This is a simplistic model and more