Adequately designed, auditory displays in Driver- Vehicle Interfaces (DVIs) may give shorter reaction times, improved attention direction, and an increased quality impression. In this paper, we argue that emotional reactions may guide the design of such auditory displays since emotion is central in our everyday life and have strong consequences for behavior and information processing. A simulator study with 30 participants (20 of which were professional drivers) was conducted to investigate the connection between emotional and behavioral responses to auditory DVIs as well as to evaluate various sound design parameters in realistic driving situations. Auditory icons were contrasted to abstract earcon sounds in more or less imminent collision scenarios and 3D sounds were tested against monophonic sounds in different lane change scenarios. Self-report measures (Self-Assessment Manikins, SAM) and physiological measures (Galvanic Skin Response, GSR and facial Electromyogram, EMG) of emotional response as well as behavioral measures (e.g. brake response time) were used.

It was found that auditory icons were more efficient and gave up to 600ms faster brake response times than abstract sounds in imminent collision scenarios and that 3D sound gave a stronger emotional response in lane change scenarios. Moreover, the results show that emotion can predict behavior, e.g. sounds rated as being more activating and negative also gave quicker response times. Contrary to our expectations however, the findings from the SAM ratings were not reflected in the physiological measurements. An explanation to this may be that the scenario itself caused a dominant stress reaction which overrode the physiological response to the warning sounds. Our findings nonetheless strengthen the importance of auditory displays as a means to enhance vehicle safety, and that emotions may be an efficient way of predicting behavioral response to auditory DVIs. Measurements of emotion may therefore facilitate the process of designing auditory DVIs.