The consequences of unexpected emotional sounds on driving behaviour in risky situations

Recent development of systems for assisted driving has raised questions about what features of the stimuli perceived by a driver may improve driving behaviour and road safety. The present study aimed to uncover whether emotional auditory stimuli can affect risky behaviour in hazardous situations. Forty-nine volunteers rode a motorcycle in a virtual environment and went through a number of preset risky scenarios, some of which were cued by a sound (a beep, a positive emotional sound or a negative sound). Results showed that hearing the beep reduced the frequency of accidents in the upcoming risky situation, while the emotional cues did not. Likewise, the beep induced the drivers to decrease their speed and focus their gaze on relevant areas of the visual field, while the emotional sounds did not. These results suggest that auditory warning systems for vehicles should avoid using emotion-laden sounds, as their affective content might diminish their utility to increase driving alertness. These findings could provide important information for the development of new advanced driver assistance systems and in general for the specification of future Human–Machine-Interaction design guidelines.