Speech-Based E-Mail and Driver Behavior: Effects of an In-Vehicle Message System Interface

Abstract

As mobile office technology becomes more advanced, drivers have increased opportunity to process information "on the move." Although speech-based interfaces can minimize direct interference with driving, the cognitive demands associated with such systems may still cause distraction. We studied the effects on driving performance of an in-vehicle simulated "E-mail" message system; E-mails were either system controlled or driver controlled. A high-fidelity, fixed-base driving simulator was used to test 19 participants on a car-following task. Virtual traffic scenarios varying in driving demand. Drivers compensated for the secondary task by adopting longer headways but showed reduced anticipation of braking requirements and shorter time to collision. Drivers were also less reactive when processing E-mails, demonstrated by a reduction in steering wheel inputs. In most circumstances, there were advantages in providing drivers with control over when E-mails were opened. However, during periods without E-mail interaction in demanding traffic scenarios, drivers showed reduced braking anticipation. This may be a result of increased cognitive costs associated with the decision making process when using a driver-controlled interface when the task of scheduling E-mail acceptance is added to those of driving and E-mail response. Actual or potential applications of this research include the design of speech-based in-vehicle messaging systems.

Accounting for time-dependent covariates in driving simulator studies

“…The data analysed in this study are from a driving simulator experiment that is representative of other studies done in this area (Lee et al 2001, Jamson et al 2004 and that was conducted in part to assess the effects of driver distractions and different strategies to help mitigate them. For a complete description of the experiment, see Donmez et al (2006).…”

“…This is a common test scenario used in driving simulator experiments, with a key performance measure being brake response time (Lee et al 2001, Jamson et al 2004. Brake response time is defined as the time from the lead vehicle braking to the release of the accelerator, and the transition time from the accelerator to the brake.…”

Synthesis of Literature Relating to Cellular Telephone/Personal Digital Assistant Use in Commercial Truck and Bus Operations

“…In a simulator-based task manipulating the control over in-vehicle messaging, Jamson, Westerman, Hockey, and Carsten (2004) found that while drivers were making adjustments in their headway (increasing their headway from a lead vehicle) during a distracting task, they were significantly less likely to anticipate the braking of a lead vehicle. This was reflected in the significant increases in braking reaction time.…”

Multimodal information presentation for high load human computer interaction

“…IVIS can even assist with driving-irrelevant tasks, such as email management and in-car infotainment [112]. Besides the obvious benefits, these IVIS functions are also distracting, and thus potentially harmful when the driver is under high load.…”

“…The recent Car2X communication technology (see Section 6.1 will allow many more functions to become available in the near future. In addition, when in-car computers have access to wireless internet, IVIS can also assist drivers in tasks that are not driving related, such as email management [112]. Besides being useful, these IVIS functions could be potentially harmful to driving safety, because they impose additional attention demand on the driver and may cause distraction.…”