Lower Executive Function Ability May Lead to Higher Perceived Mental Workload in Driving Scenarios

Driver mental workload may represent a mismatch between task demands and available mental resources. If driving mental workload arises from a mismatch involving executive functions, then drivers with more executive function ability should perceive less mental workload in driving situations. To test this hypothesis, 33 participants rated the mental workload associated with 16 driving scenarios and also carried out three cognitive assessment games designed to measure executive functions (response inhibition, working memory updating, switching/shifting). We found a significant relationship between two of the executive function abilities (response inhibition, and switching/shifting, but not working memory updating) and mental workload ratings. With an increase in the age of participants, we observed lower response inhibition and higher perceived mental workload after viewing representations of driving scenarios. These results demonstrate that previous results showing higher perceived mental workload for older drivers may be, at least partly, due to decreases in executive function ability as people age.