The Smartphone and the Driver's Cognitive Workload

The Smartphone and the Driver’s Cognitive Workload: A Comparison of Apple, Google, and Microsoft’s Intelligent Personal AssistantsPhase IIIA - Cognitive Distraction While Driving

Nearly every vehicle sold in the U.S. and Europe can now be optionally equipped with voice-controlled functions, to allow drivers to maintain their eyes on the road and hands on the wheel. The objective of this research was to examine the impact of voice-based interactions using three different intelligent personal assistants (Apple’s Siri, Google’s Google Now, and Microsoft’s Cortana) on the cognitive workload of the driver.

Performance while “on task,” or manipulating the phone, was associated with surprisingly high levels of workload.  Also, there were significant differences in the distraction experienced by the driver when they used the different smartphones to perform the same tasks.

Finally, data showed evidence of lingering distraction, for up to 20 seconds, after the driver finished interacting with the device.

Final Report

Fact Sheet


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