A new AAA study on driver cognitive distraction concludes that as mental workload and distractions increase, drivers’ reaction time slows, their brain function is compromised, and they scan the road less and miss visual cues. As a result, these drivers see fewer items right in front of them, including stop signs and pedestrians.

The research project teamed the AAA Foundation for Traffic Safety and the University of Utah. Citing the study results, AAA is urging drivers not to use voice-to-text features while their vehicle is in motion. The organization sees the growing prevalence of voice-activated infotainment systems as a safety risk.

“There is a looming public safety crisis ahead with the future proliferation of these in-vehicle technologies,” said AAA President and CEO Robert L. Darbelnet. “It’s time to consider limiting new and potentially dangerous mental distractions built into cars, particularly with the common public misperception that hands-free means risk-free.”

Cognitive distraction expert Dr. David Strayer and his research team at the University of Utah measured brainwaves, eye movement and other metrics to assess what happens to drivers’ mental workload when they attempt to do multiple things at once. The research included:

  • Cameras mounted inside an instrumented car to track eye and head movement of drivers.
  • A detection-response-task device known as the “DRT” to record driver reaction time in response to triggers of red and green lights added to their field of vision.
  • A special electroencephalographic (EEG)-configured skullcap to chart participants’ brain activity so that researchers could determine mental workload.

Researchers relied on established protocols borrowed from aviation psychology and a variety of performance metrics.

Drivers engaged in common tasks, from listening to an audio book or talking on the phone to listening and responding to voice-activated emails while behind the wheel. Researchers used the results to rate the levels of mental distraction drivers experienced while performing each of the tasks. Similar to the Saffir-Simpson scale used for hurricanes, the levels of mental distraction are represented on a scale:

  • Tasks such as listening to the radio ranked as a category “1” level of distraction or a minimal risk.
  • Talking on a cell-phone, both handheld and hands-free, resulted in a “2” or a moderate risk.
  • Listening and responding to in-vehicle, voice-activated email features increased mental workload and distraction levels of the drivers to a “3” rating or one of extensive risk.

“These findings reinforce previous research that hands-free is not risk-free,” said AAA Foundation President and CEO Peter Kissinger. “Increased mental workload and cognitive distractions can lead to a type of tunnel vision or inattention blindness where motorists don’t see potential hazards right in front of them.”

Citing this research, AAA said it is urging the automotive and electronics industries to explore:

  • Limiting use of voice-activated technology to core driving-related activities such as climate control, windshield wipers and cruise control, and to ensure these applications do not lead to increased safety risk due to mental distraction while the car is moving.
  • Disabling certain functionalities of voice-to-text technologies such as using social media or interacting with e-mail and text messages so that they are inoperable while the vehicle is in motion.
  • Educating vehicle owners and mobile device users about the responsible use and safety risks for in-vehicle technologies.

AAA added that it is also using the study results to promote dialogue with policy makers, safety advocates and industry “to ensure that these emerging in-vehicle technologies won’t lead to unintentional compromises in public safety.”