The impacts of task relevance and cognitive load on adults' decision information search

Higher relevance may increase older adults' engagement in cognitively demanding activities; however, whether this effect will maintain when available cognitive resources are limited? Consequently, we investigated the joint impact of task relevance and cognitive load on older and younger adults' decision search behaviors. We adopted a 2 (age: young/old) × 2 (cognitive load: without load/with load) × 2 (task relevance: high/low) mixed design. Sixty-one younger and 63 older adults completed high-relevance and low-relevance decisions. Our results revealed that older (vs. younger) adults took more time and more alternative-based search before decision-making. Both age groups sampled less information with an additional memory task. Additionally, they spent more time and effort to sample more information on high-relevance (vs. low-relevance) decisions; however, such differences disappeared when with an additional memory task. Task relevance promoted both age groups' search engagement, but this effect was subjected to their available cognitive resources.