09 | How carsickness affects cognitive and driving performance – a comparison

Background: Motion sickness can impair cognitive and physical performance.1 As a subtype, carsickness is expected to become more prevalent in automated driving.2 However, drivers must still safely control the vehicle during and after takeover situations. Our two studies investigated how carsickness affects driving-relevant cognitive and actual driving performance. Materials and Methods: Study1 involved N=67 participants and focused on cognitive tasks reflecting key driving aspects: visual selection (visual search), reactions to sudden events, visuo-spatial ability (mental rotation), and hand-eye coordination (tracking). Tasks were completed before and after a carsickness-inducing ride as a front passenger in a real vehicle. Based on these results, Study2 used a Wizard-of-Oz vehicle on a test track to simulate automated driving. N=33 participants performed four driving tasks after a takeover request, with and without carsickness: emergency braking, target braking, free speed slalom, and 25 km/h slalom. Results: Participants in both studies reported subjective impairments. They felt their performance declined, tasks were more demanding, and driving partly more critical. However, objective results varied. Study1 showed longer reaction times, impaired hand-eye coordination, and a tendency toward reduced visuo-spatial ability. In contrast, performance in Study2’s driving tasks did not significantly differ between carsickness and baseline. Thus, the expected impairments from Study1 were not confirmed in real driving.