Psychological approaches to the treatment of chronic pain.

Much of the earlier writing on the psychology of pain fails to distinguish between acute pain and chronic pain. Some authors studied chronic pain, explicitly defining their population by the duration of the complaint. The differences between acute and chronic pain were particularly emphasized by Sternbach (1968, 1974). Watson (1983) delineates chronic pain very effectively as follows: '.... persisting past one month or past the usual time for the particular disorder to heal. It usually lacks evidence of autonomic hyperactivity'. A number of the psychological observations which apply to acute pain also apply to chronic pain. But not all of them matter as much. For example, anxiety and anticipation often make acute pain worse. This is particularly notable before operation. They are not nearly so prominent in respect of chronic pain. Similarly a sense of control of the situation often eases acute anxiety or pain. This can be inferred from the animal literature, e.g. Mowrer and Viek (1948) and has sometimes been shown in adults (Bowers, 1968; Thompson, 1981), and in children (McGrath, 1983). It has been generally considered since the work of Beecher (1955) that a placebo effect can be found in 35% of patients with postoperative pain and other acute conditions. This is rarely the experience of anyone treating chronic pain. In the case of chronic pain, patients are often no longer anxious but are more often depressed. Many of them have learnt, or have taught themselves, subjective techniques of pain control. Frequently, these involve distractions or an alternative method of occupation. Sometimes they find a way to occupy themselves with a task in the presence of distracting stimuli which are deliberately provided; usually this is the radio. It is interesting that Morgenstern (1964) demonstrated that a combination of tasks and distracting stimuli, like flashing lights and variable repeated noises helped to reduce pain. However, if patients do reach the doctor for treatment it can be assumed that even though their efforts in this direction may have had some success, they have not been enough to produce the relief which is needed.