Compensatory Control under Stress

Modern treatments of psychological stress emphasize the cognitive transactions that mediate between stressful events and the adaptive response to them. This appraisal process evaluates the implications of the stressor for both current activities and personal well-being. In terms of performance tasks, this may mean focusing information processing resources more strongly on the task (performance protection) or withdrawing resources in order to combat the stressor itself.

This latter reaction is likely to be more effective in reducing the effects on bodily or emotional states, but it inevitably leads to a loss of performance goals. Performance protection is the usual response in everyday situations in which the individual is highly skilled, the task sufficiently important, and the stressor familiar and manageable. Serious disruption is rare for high-priority activities and is usually associated with traumatic events.

This is because a compensatory process operates to maintain the primary task goals under the increased threat of disruption, resulting in a reduced response to the control of the emotional state and other competing goals.

The increased effort underlying compensatory control is considered to reflect the involvement of the central executive functions responsible for the maintenance of high-level cognitive behavior, as observed in problem solving, reasoning, and all goal maintenance activity. As such, it is a limited resource that inevitably attracts costs when it is overemployed.

On the other hand, we know that decrements are relatively common, especially in laboratory studies or where skill and motivation are low. Within this framework, the specific patterns of decrement outlined earlier may be considered a baseline or default pattern of decrement under different stressors - how performance might be expected to suffer in the absence of compensatory control activity. As an example, consider a pair of studies carried out in Stockholm in the 1980s.

They showed that noise impaired performance on an arithmetic task on one occasion but not on another. How can this be understood? The answer is related to motivational factors such as compensatory effort. The investigators also measured the physiological and subjective costs associated with having to work on the task under noise. In the study in which performance was unimpaired, they observed a marked increase in adrenaline and ratings of subjective effort. However, in the case in which performance was disrupted by noise, no such changes were observed.

The most satisfactory explanation of this (and other similar) findings is that noise imposes an additional load on our capacity to maintain adequate orientation toward the task. If we can make an additional effort under such circumstances, performance may be protected against disruption, although only at the cost of increased strain in other areas.

Alternatively, we may be unwilling (or unable) to make such an effort, in which case we will experience less strain but inevitably suffer a decrement in task performance. Such trade-offs are the routine consequences of having to manage stress and other environmental demands while still carrying out our commitments to external task goals.