Dual tasking from a goal perspective.

In many if not all situations humans are engaged in more than one activity at the same time, that is, they multitask. In laboratory situations, even the combination of two simple motor tasks generally yields performance decrements in one or both tasks, compared with corresponding single task conditions. In contemporary models of dual tasking, these dual task costs are attributed to a capacity-limited stage of mentally specifying required responses. Ideomotor theory suggests that the generation of responses is a process of specifying goals, that is, desired future perceptual states (= effect anticipation). Based on this, we argue that effect anticipation is the process responsible for dual task costs. We substantiate this suggestion with results from several lines of research, showing that (a) effect anticipation coincides with a capacity-limited process in dual task experiments, (b) no dual task costs arise if no effects are to be anticipated in one of the tasks, (c) dual task costs vary as a function of a how well effects from two tasks fit together, and (d) monitoring the occurrence of effects also adds additional costs. These results are discussed in a common framework and in relation to other observations and fields. (PsycInfo Database Record (c) 2020 APA, all rights reserved).