Effects of anticipatory auditory cues and non-driving related tasks on motion sickness in automated vehicles

In the context of highly automated vehicles, motion comfort deserves crucial attention for their widespread adoption. Passengers of automated vehicles are prone to motion sickness from diminished cognizance of the driving environment, and from engaging in non-driving related tasks (NDRTs). Awareness about upcoming motion and mental distraction from NDRTs have the potential to mitigate motion sickness. The current study used a motion-based driving simulator where 31 participants performed easy and hard versions of an NDRT in the presence and absence of spatialized anticipatory auditory cues displayed 3 s prior to lateral accelerations over a 20-min drive in a fully automated vehicle. Results suggested that anticipatory cues may only be effective when displayed selectively on an as-needed basis for both lateral and longitudinal accelerations. Sufficient cue-motion association internalization through training or continued exposure may also be required for anticipatory cues to be effective. Further, regardless of the cognitive demand of the NDRT, some form of mental distraction has the potential to suppress motion sickness.