ABSTRACT
Training in complex, multiple-component tasks must extend beyond the attainment of a criterion level of performance to that of 'overlearned behaviour'. Such a learning state is characterised by automatisation of sub-skills and freeing of mental resources to cope with other concurrent demands or stressful circumstances (in simplistic terms, greater 'spare mental capacity'). Conventional measures of performance are insensitive to changes during overlearning, whereas many workload measures are specifically designed to indicate spare capacity. The term workload in the context of training is defined as the 'effort' that an individual has to invest to achieve a certain level of performance. In the context of scenarios or tasks, workload is often referred to as reflecting the external demands imposed by the situation. For experienced operators a high external workload does not necessitate a high individual workload, due to the extensive level of practice. The same conditions, however, may result in overload for a less experienced operator or a trainee.
