CONTROL & UNPREDICTABILITY
There are obviously individual differences in people's vulnerability to stress, nonetheless research has indicated that there are some features to events which make them more likely to be perceived as stressors.
These are LACK of CONTROL
CONFLICT & FRUSTRATION
Studies with both animal & human subjects have shown that UNCONTROLLABLE SITUATIONS are highly stressful. WEISS (1972) found that if 2 RATS simultaneously received ELECTRIC SHOCKS of the same intensity & duration, but one could turn a wheel to postpone the shocks, the rat without any control option displayed a lower immunity to decease.
The LACK of CONTROL over an event often results in the person being stressed. GEER & MAISEL (1973) found through showing 2 Groups colour transparencies of victims of violent deaths. Participants in Group 1 were told they could stop the "slide show" by pressing a button. Those in Group 2 were not given this option.
The 2 Groups saw the pictures for the same length of time. However, the results showed that Group 2 (those without the stop button) found the viewing more stressful. Stress was measured by electrical resistance of the skin, which shows the level of arousal in the autonomic nervous system. This experiment suggests that the perception of having control over the situation WILL affect the level of stress being encountered.
Research on UNPREDICTABILITY by Psychologists, studying the behaviour of people from OTHELLO, not far from SAINT HELEN'S, were the most powerful volcano eruption occurred in 1980. There were apparent warnings of the eruption, but no-one could predict the time scale or scale of the blast. As it was 60 people died, 150 miles was destroyed from the hot ashes. After the blast Psychologists found 198% increase in illness related to stress a 235% increase in MENTAL Health problems, resulting...