Effects of Task Structures on Attention Allocation Optimality

Abstract

The experiment reported examined the hypothesis that more optimal allocations would occur between time-shared tasks that place heavy demands on common processing resources (similar task structures) than tasks that utilize separate resources (dissimilar task structures). Two dual task configurations differing in their degree of demand for common resources were employed. The structurally similar pairs consisted of two compensatory tracking tasks whereas the dissimilar pair consisted of a tracking and a short term memory task. Demand for common resources was further manipulated by employing four combinations of different I/O modalities for the memory task. Relative use of the task-specific resources were manipulated through priority instructions and dynamic difficulty changes. Results generally support the hypothesis and suggest that certain dimensions that defined the resources (stages of processing, I/O modalities, and processing codes) assert greater influence on allocation optimality than others. Implications for decisions on multitask designs were speculated.