Proceedings of the Annual Meeting of the Cognitive Science Society

In simple judgment tasks, it is generally assumed that thinking for longer leads to more accurate judgments, providing better benefits as suggested by the speed-accuracy tradeoff framework. However, human cognitive resources are limited, and longer thinking induces cognitive costs such as subjective workload. Therefore, a total benefit should be considered under the tradeoff between thinking benefits (i.e., improving accuracy) and thinking costs (i.e., increasing cognitive load) as suggested by the resource rationality framework. We examined this issue using computer simulations and behavioral experiments. Our simulations showed that, if a thinking cost was introduced based on resource-rational approaches, there was an optimal length of time for maximizing a total benefit and the total benefit gradually decreased there. In addition, our experiments demonstrated that judgment accuracy did not always improve even if participants were provided a longer thinking time; conversely, longer thinking time was likely to increase their subjective workload. These results are consistent with resource rationality rather than speed-accuracy tradeoff. The importance of considering cognitive load is suggested to further understand human intelligence in the context of a speed-accuracy tradeoff.