Cognitive Load and External Representation of Tower of Hanoi Problem-Solving Rules

Abstract

Problem-solving often represents a highly demanding situation for working memory recourses. When dealing with new and complex problems, the number and interactivity of problem elements which could be processed simultaneously could exceed the available capacity of the working memory. External representation could significantly increase the effectiveness of problem-solving because they reduce the cognitive load. Our study was conducted with the aim to investigate the effects of external representation on solving success and cognitive load of Tower of Hanoi problems. The participants were 30 students of Department of Psychology, Faculty of Philosophy in Sarajevo. The participants solved three isomorphic variants of Tower of Hanoi problem taken from the Zhang and Norman (1994) study. With different variant, the number of external rules varied. Cognitive load was measured with the Questionnaire of cognitive load (Paas, 1992).The results obtained in our research show that the efficiency of problem-solving increases with the number of external rules. This result is in accordance with results obtained in the Zhang and Norman (1994) study. External rules decrease subjective estimate of mental effort and increase the understanding of the problem. There are no differences in estimation of the difficulty of problems.Results of our study confirm the findings of the previous study that the external representations contribute to effective problem-solving of the complex problem. In addition, external representations reduce cognitive load. Generic strategies impose a high cognitive load per se, which cause high estimate of problem difficulty, regardless of the objective difficulty of a problem.