Abstract

Measuring Cognitive Distraction in the Automobile III: A Comparison of Ten 2015 In-Vehicle Information Systems

Objective

• The objective of this research was to examine the impact of IVIS (in-vehicle information systems) interactions on the driver’s cognitive workload.

Methods

• The selected tasks and experimental structure were designed to extend prior work using embedded vehicle systems:
  • Evaluated cognitive demands of 10 2015 vehicles’ IVIS
    • 257 subjects participated; 127 males and 130 females, with an average age of 44 and divided into three age categories: young (21-34), middle aged (35-53) and old (54-70).
    • 6 distinct tasks were given to participants utilizing the vehicles’ unique voice activated information system – including contact calling, number dialing, and music selection while they were driving.
    • Post-test evaluation captured participants’ results after a week of practice time with the tasks in the research vehicle.
    • Cognitive workload was assessed on a 5-point scale, where 1 represented just driving (no interaction with IVIS) and 5 represented the workload associated with the OSPAN task (mentally challenging math and memory tasks).

Key Findings

Major Findings:

• (IVIS) use is associated with moderate to high levels of cognitive distraction for the driver.
  • Overall workload ratings associated with IVIS interactions ranged from 2.37 to 4.58, which depicts a moderate to high level of cognitive workload – while drivers were at no time required to take their eyes off the road or hands off the wheel.
• Practice doesn’t eliminate the cognitive distraction caused by IVIS interactions.
  • Practice improved IVIS interactions slightly, but intuitiveness and complexity ratings were not affected as a result of practice.
• Older drivers experience a higher level of cognitive distraction with IVIS interactions, compared to younger and middle-aged drivers.
  • Older adults also rated IVIS interactions as more complex than the two younger groups.
• There were considerable differences in the cognitive workload of the different IVIS systems
  • Chevy Equinox MyLink had the lowest rating, while the Mazda 6’s Connect had the highest rating on the cognitive workload scale.
  • Robust, intuitive systems with lower levels of complexity and shorter task durations result in less cognitive distraction.
• Cognitive distraction associated with task performance was surprisingly high
  • Serves as a warning that “hands-free” technologies can be very cognitively demanding.
  • Compared to our earlier research, many of the IVIS interactions appear to be significantly more demanding than typical cell phone conversations (rated 2.3 on the same scale).
• There were residual costs after IVIS interactions were over.
  • Just because a driver terminates a call or music selection doesn’t mean they are no longer impaired – impairment lingered up to 27 seconds after a task was completed.