Study: Even with your eyes on the road, mental distractions affect safety

Hands-free technologies might make it easier for motorists to text, talk on the phone, or even use Facebook while they drive, but a new AAA Foundation for Traffic Safety study shows dangerous mental distractions exist even when drivers keep their hands on the wheel and eyes on the road.

With a predicted five-fold increase in new vehicle infotainment systems by 2018, AAA sees a major on-the-road public safety crisis ahead  is calling for action as a result of this ground-breaking research.

“There is a looming public safety crisis ahead as the number of these in-vehicle technologies increase,” said Lloyd P. Albert, AAA Southern New England senior vice president of public and government affairs.

“It’s time to consider limiting new and potentially dangerous mental distractions that are built into cars, especially since there’s a common public misperception that hands-free means risk-free.”

The research, conducted at the University of Utah, found as a driver’s mental workload and distractions increase:

  • Reaction time slows;
  • Brain function is compromised; and
  • They scan the road less and miss visual cues, such as stop signs and pedestrians, who at times can be right in front of them.

This is the most comprehensive study of its kind to look at the mental distraction of drivers and arms AAA with evidence to appeal to the public to not use these voice-to-text features while their vehicle is in motion,  Albert said.


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.

To study reaction times, Dr. Strayer:

  • Mounted cameras inside an instrumented car to track eye and head movement of drivers;
  • Used a Detection-Response-Task (DRT) device to record driver reaction time in response to triggers of red and green lights added to their field of vision; and
  • Charted participants’ brain activity using a special electroencephalographic (EEG)-configured skull cap so researchers could determine mental workload.

In the study, researchers rated various levels of distraction, representing them on a scale similar to the one used for hurricanes.

For example:

  • Tasks such as listening to the radio, ranked as a category “1” level of distraction – a minimal risk – but still a risk;
  • Talking on a cell phone, both handheld and hands-free, resulted in a level “2” – considered moderate risk, depending upon the nature of the conversation; and
  • Listening and responding to in-vehicle, voice-activated voice mail, dialing, and email features increased mental work load and the distraction level of drivers. This was rated as a “3” – one of extensive risk.

Based on the research, AAA urges the auto and electronics industries to find new ways to:

  • Limit the use of voice-activated technology to core driving-related activities, such as climate control, windshield wipers; and cruise control;
  • Ensure these applications don’t lead to an increased safety risk because of mental distraction while the car is moving;
  • Disable certain functionalities of voice-to-text technologies such as using social media or interacting with email and text messages so they’re inoperable while the vehicle is in motion; and
  • Educate vehicle owners and mobile device users about the responsible use and safety risks for in-vehicle technologies.

“This study constitutes the most in-depth analysis to date of mental distractions behind the wheel,” said  Albert.  “AAA hopes it will serve as a stepping stone to collaborate with automakers to promote our shared goal of improving safety for all drivers. Specifically, these increasingly common voice-driven, in-vehicle technologies should be limited to use for just core driving tasks unless the activity results in no significant driver distraction.”

To view the full Cognitive Distraction in the Vehicle report or AAA’s Distracted Driving Fact Sheet, visit