Psychological Explanations of Stress

The experience of stress consists of two major components; stressors and the stress response. A stressor is a stimulus that causes a person to make an adaptation or adjustment. Stressors can be external in the form of crowding or heat, social such as contact with a hated one or internal such as pain. Such experiences result in psychological and biological responses, this is termed, the stress response.

Arousal 
Much of the early work on stress focused on physiological responses. These responses create or preserve attentiveness and energy, for instance, increases heart rate so blood rushes to the muscles quickly. Arousal is often accompanied by highly emotional and active states. When we experience anger or fear, we are likely to be in a state of bodily arousal. Arousal is also related to performance; according to the Yerkes-Dodson Law, too much arousal or too little arousal results in poor performance. There is an optimum level of arousal for high performance.

The Fight or Flight Response 
In the event of a stressful situation, there is an immediate biological reaction. Blood drains from the face, stomachs turn over and muscles tense. This is known as the fight-or-flight response; the body prepares to fight to defend oneself or flee. If little or nothing is done to reduce arousal, one can stay in a heighten state of arousal for a long period of time. In some situations this can also be termed the "arousal cost-reward model" , Piliavin et al argue that in situations where someone is confronted with helping an individual of not they first feel physiological arousal then weight up the cost and benefits of helping. Helping would reduce the arousal, as would fleeing the situation.

General Adaptation Theory 
In the 1930s, Selye developed the concept of General Adaptation Theory. He suggested that there are three stages that describe the response to long term stress: 
-Alarm reaction; at this stage the body's resources are mobilised. Initially, arousal drops below normal, then it rapidly rises above normal. If the body remains in the alarm reaction for a long period of time, ill health and even death, could follow. 
-Resistance; at this stage the body accepts the stressor. Physical arousal declines but remains above normal. There are few outward signs of stress but the ability to resists stressors is impaired and the individual becomes vulnerable to diseases of adaptation such as ulcers and High Blood Pressure. 
-Exhaustion; eventually, the body's resources energy reserves become depleted and the and the ability to resists declines. If stress continues, disease, damage and disease can follow.

Cognitive Appraisal Theory 
Lazarus et al (1965) defines stress in terms of 4 stages: 
-Stressor; an external event 
-Primary appraisal; whether the event is positive or negative and how harmful or threatening it is 
-Secondary Appraisal; are the individual's coping strategies sufficient? 
-Stress; physiological, cognitive, emotional and behavioural responses

Lazarus carried out a study to investigate Cognitive Appraisal Theory. Participants were shown gruesome and stressful films of accidents in a wood workshop. There were three groups, one was told the film was acted, another was told the events were real but would help improve safety and the third was a control group given no explanation. The two groups given instructions showed less arousal (the primary appraisal showed the films as positive). Positive cognitive appraisal, seeing the events as none threatening, reduces stress.