Disentangling cognitive from perceptual load using relational complexity

Abstract

ABSTRACT Debate centres on the difficulty to distinguish precisely whether cognitive or perceptual load determines performance in tasks such as the Halford Graphical Relational Complexity Task (HGRCT). In this task, visual information is presented, and participants are asked to perform a series of mental operations that require working memory (WM) to complete the task. This study compared performance on purely visual as well as a cognitive task over arity, defined as the “amount of information to be remembered” and so a measure of working-memory load. Errors increased generally with increasing arity. However, reaction-time (RT) slopes revealed small to moderate increases over arity for the visual task while there was a major increase in the RT slope in the cognitive task. It cannot be ruled out that visual information load increases task difficulty, however, the difference in magnitude of the RT slopes over arity indicates that resolving the HGRCT is mainly dependent upon performance in cognitive mechanisms and may be relatively uninfluenced by the performance of perceptual memory systems.