An Empirical Demonstration of Multiple Resources

Abstract

Earlier work by Gopher, Brickner, and Navon (1982) suggested that evidence for multiple processing resources can be demonstrated only if both task difficulty and task priorities are manipulated in dual task studies. To further investigate their approach, ten subjects performed both single and dual task versions of a tracking task and a vowel insertion task, the latter modified to increase either motor load or cognitive load. Dual task trials required equal task emphasis on the favoring of one task over another. As expected, a difficulty by priority interaction was found in the motor load but not in the cognitive load condition, suggesting multiple resources. Performance Operating Characteristics for these data suggested that more than two resources were being utilized by these tasks.