Temporal Analysis of Cognitive Workload During Manual and Partial Driving Automation Based on the Detection Response Task

Present-day automated driving systems (ADS), though still under development, require drivers to remain attentive and responsible, yet research suggests that drivers are often misled into believing otherwise. This study examines the cognitive workload experienced by drivers based on the tactile detection response task, a standardized task for assessing the impact of cognitive load on attention during secondary driving tasks. Participants drove four different vehicles on two highways at two ADS levels (manual and partial automation), creating 16 on-road experimental conditions. In each condition, approximately 45 participants drove for about 20 minutes. The analysis investigates the temporal trends in participants' response times across these conditions. Results indicate that the response time increased with driving duration, suggesting an increased cognitive load throughout the 20-minute drive across 15 of the 16 conditions. Furthermore, no significant differences were found in the temporal trend of cognitive workload between manual and partially automated driving, which aligns with previous research.