Psychology Chapter 4 - Arousal and Stress

Arousal – Refers to the overall state of alertness and activation of an individual Our state of alertness is often associated with stimulation of one or more of our senses and/or our thought process E.g. sound of screeching car breaks close by can heighten our arousal

Activation of the sympathetic nervous system.
The adaptive response that occurs automatically, resulting an increase of arousal that prepares the body to confront the stressor (fight) or running away (flight). The fight-flight response maximises our chances of survival when confronted by a threat.

Researchers have found out there is an optimal level of arousal or a comfortable level of alertness at which people can perform efficiently. E.g. performing well on an exam requires students to have a certain level of overall arousal · If they were tired bored – low level of arousal – they will perform badly · If they are extremely worried, anxious – high levels of arousal – they will also perform badly · Studies have found out that people generally perform most effectively at a moderate level of arousal (Hebb, 1955) · Performance tends to deteriorate with either significantly lower or higher levels of arousal

· when data on arousal/performance is plotted it forms the shape of a reflected parabola and is known as the Yerkes-Dodson law (Yerkes & Dodson, 1908)

· The level of arousal for optimal performance depends on the complexity of tasks. · Complex or unrehearsed tasks (unskilled) - the optimal performance - arousal is somewhat lower. · Simple tasks – Optimal performance - arousal is relatively high · Another important consideration is determining the skill of the athlete in sports and the complexity of the task. E.g. the task of dribbling a basketball for a beginner requires more concentration, and a lower level of arousal than an expert performing the same task (Oxedine, 1970)

A device that detects/records several physiological responses at the same time, enabling measurement of general bodily arousal

'lie detector’
polygraph typically records changes in heart, blood, respitory rate and of the electrical conductivity of skin (Galvanic skin response, GSR)

Stage #3 – Exhaustion – signs of alarm reaction may reappear, but the effects of the stressor can no longer be dealt with - prolonged deal with the stressor has has depleated the body's mental, emotional and physical resources.
- Immune system is weak becomes vulnerable to psychological/physical illness - Extreme fatigue, high levels of anxiety, depression, nightmares, impaired sexual performance, and ulcers may occur and continuation of stress may lead to death - Hormones (adrenalin, cortisol) remain at high levels for prolonged time, they can cause damage to the heart and suppress the functioning of the body

Genuine phsyical symptons caused by psychological factors

 Interest in the relationship between stress and disease led to the emergence 1980s of a specialised area of psychology
– Psychonueroimmunology –
focuses on the connection between psychological factors (psycho) the nervous system (neuro) and in the immune system (immunology) in disease. Its basic assumption is that an onset and course of a disease results from a complex interaction of all these systems. Researches involved have also found out that intense stress, especially if its’ prolonged leads to the impairment of the body’s immune system

Various research studies found out that stress contributes to the ineffective functioning of the immune system E.g. hormones that are released during the flight-fight response, while preparing our body for the perceived threat, may also suppress the activity of the immune system. So it has been proposed that harmful cells entering the body may not be detected quickly enough to be eliminated, resulting in illness.

Activates the sympathetic division of the autonomic nervous system, increasing levels of arousal, heightening our awareness/alertness and prepare us for the threat.

Stage #2 – Resistance – body’s resistance to the stressor increases - Intense arousal of the alarm reaction stage diminishes, but physiological arousal remains a level above normal - cortisol released (repairs damage to body but weaken the immune system) are released into the bloodstream - Although resistance to the stressor increases, resistance to disease declines

This is stage one individual's awareness of the stressor

Shock stage - body goes into temporary state of shock, and its ability to deal with the stressor falls below its normal level.
body physiologically acts as though it is injured e.g. body temperature drops.

Couner-shock stage -
the activation of the sympathetic division
increase of arousal and the body's resistance to the stressor increases.
Body becomes highly alert as it is prepared to deal with the stressor.

Dilated pupils - more light can enter the eye and enhance vision
Release of hormone adrenaline - releases energy for action
Increased heart rate -increases blood flow to brain and muscles
Increased blood pressure - increases flow of oxygen to body