Effectiveness and user acceptance of infotainment-lockouts: A driving simulator study

•This driving simulator study examined a driver distraction mitigation strategy that is referred to as a lockout.•A lockout disabled functionalities of in-vehicle information systems with the aim of reducing distraction.•A lockout improved driving performance in the lateral but not in the longitudinal direction.•User acceptance decreased with an increasing amount of disabled functionalities while the vehicle was in motion.•A successful implementation of the strategy should incorporate both driving performance and user acceptance. Lockout is a system-initiated distraction mitigation strategy that renders certain features of in-vehicle information systems (IVISs) non operable while the vehicle is in motion. The aim of this driving simulator study was to examine the influence of lockouts on driving performance and user acceptance. Overall, 52 participants performed six tasks with fully unlocked, partially locked, and completely locked IVIS. Within a repeated-measures design, we assessed user acceptance. As participants were free to decide where to conduct a secondary task, we could only analyse driving performance of 26 drivers. After each driving section, the participants rated the respective system with respect to acceptance. Driving performance with regard to lateral control was better when the system employed partial or complete lockouts as compared to the unlocked system. In contrast, longitudinal control did not benefit from a lockout. User acceptance decreased with an increasing number of disabled system functions while driving. Thus, lockout as a distraction mitigation strategy comes at the price of reduced user acceptance. To improve acceptance, one could attempt to make the secondary tasks less attractive (e.g., by public campaigns) rather than prohibit them through lockout. In addition, human-machine interfaces in the vehicle could be improved in order to reduce their demands on attentional resources.