The Aftereffects of Stress

Adverse aftereffects of stress, such as decreases in performance and attention span, are also well documented. In fact, one of the reasons that stress presents both a health hazards and a challenge to the health psychology researcher is that the effects of stress often persist long after the stressful event itself is no longer present. Aftereffects of stress have been observed in response to a wide range of stressors, including noise, high task loads, electric shock, bureaucratic stress, crowding, and laboratory-induced stress. In a series of studies, college student participants are put to work on a simple task and expose them to an uncontrollable, unpredictable stressor in the form of random, intermittent bursts of noise over a 25-minute period. After the noise period was over, these participants were given additional tasks to perform, including solvable and unsolvable puzzles and a proofreading task. The participants who had been exposed to the noise consistently performed more poorly on these tasks. These results have been confirmed by other investigators.

Stressors can produce deleterious aftereffects on social behavior as well as cognitive tasks. Several studies have found that when people are exposed to avoidable stressful event, such as noise or crowding, they are less likely to help someone in a distress when the stressor is over. For example, in one study, people shopped in a shopping centre that was either crowded or uncrowned and were required to purchase a large or a small number of items in a short period of time. Later, all the shoppers encountered a woman who pretended to have lost a contact lens and who requested help finding it. The people who had had to purchase lots of items in a short period of time or who had been more crowded were less likely to help the woman than were that people who had had few things to buy and more time to shop or who had shopped in less crowded condition.

The fat that stressful events produce aftereffects should not be surprising. Even simply arriving late to an exam may leave the heart racing for half an hour, interfering with effective performance, exposure to a stressor over a longer period of time may have cumulative adverse effects so that reserves are drained and resistance breaks down when a person has to cope with a new stressful event. Unpredictable and uncontrollable stressful events appear to be particularly likely to produce deleterious aftereffects.