If the stressful situation is very intense or continues over a period of time, the adrenal cortex becomes increasingly involved in the stress reaction. The activity of the cortex is largely controlled by blood levels of adrenocorticotrophic hormone (ACTH, which is released by the anterior pituitary gland. When information about sustained stress has been "processed" by the central nervous system, a whole range of new bodily responses occurs, and it is these longer-term reactions that can adversely affect the quality of life.

Psychological Responses
In general terms, the psychological reaction to stress takes the following course:

• The initial fight-or-flight reaction is accompanied by emotions such as anxiety or fear.
• Individual ways of coping are activated as we attempt to find a way of dealing with the harmful or unpleasant situation.
• If the coping strategies are successful, the fight-or-flight reaction and the anxiety state subside.
• If the coping strategies fail and the stress situation continues, a range of psychological reactions, including depression and withdrawal, may occur.

The implication is that the consequences of failing to cope can be serious, and it is therefore important that we develop our own ways of adapting to and successfully dealing with stressful situations.

Research about how we cope suggests two broad categories of coping strategies. The first involves attempts to change our unsatisfactory relationship with the environment. Examples of this category would be:

• Escaping from the unpleasant situation-not always possible!
• Preparing ourselves for situations that we anticipate will be stressful. This might involve thinking ahead of time about the situation and its likely impact, thereby preparing ourselves adequately for the event; or it might involve some actual work - for example, studying for an exam, instead of just worrying about it.

• Denial, by which we refuse to acknowledge all or some of the threat in the situation.
• Intellectualization, by which we detach ourselves emotionally from the situation.

Both of these strategies serve to protect us and help us maintain a reasonable equilibrium through difficult times, but there is always the danger that such strategies may make it more difficult for us to resolve a problem and may become established as part of our psychological makeup.

Other coping strategies, including various relaxation techniques, may be appropriate in some or all cases. However, the use of such strategies may delay the direct reaction that we need to solve the problem that is causing the stress. This is also true of another, particularly destructive way of coping: escaping via the use of alcohol, tranquilizers, or other drugs.

There are some stresses for which no clear solution exists, for example, caring for the chronically ill - and in such situations softening the impact of stress may be the only way for us to cope. If stress is long-term or particularly severe, marked emotional changes may take place. If the coping strategies we employ don't work, we may regard the situation as one for which there is no solution and increasingly see ourselves as unable to control the events of our lives. Hopelessness and helplessness are both likely to give rise to feelings of depression, and may even lead to suicidal thoughts. Following the stress of chronic illness, for example, patients may literally give up hope. If this occurs, they may become not only emotionally disturbed but also more vulnerable to further physical illness.