APA Dictionary of Psychology

a model that views attention as a single pool of undifferentiated resources that can be devoted to a variety of processes. Tasks place demands on the general pool, rather than on particular resources. The extent to which the total resources are taxed by a primary task will determine the performance decrement on other tasks carried out at the same time; when the demand on resources exceeds the supply, allocation strategies become important. Also called single-capacity model. Compare multiple-resource model.