Just because you’re using your voice instead of your hands to give Cortana a command while driving doesn’t mean you’re playing it safe.
Motorists can be distracted for as long as 27 seconds after issuing voice commands to their smartphone or in-car infotainment system, University of Utah researchers found in a pair of new studies funded by the AAA Foundation for Traffic Safety. The studies indicate that going hands-free while behind the wheel can be much more dangerous than many of us might believe.
"The lasting effects of mental distraction pose a hidden and pervasive danger that would likely come as a surprise to most drivers," Peter Kissinger, president and CEO of the AAA Foundation for Traffic Safety, said in a press release. "The results indicate that motorists could miss stop signs, pedestrians and other vehicles while the mind is readjusting to the task of driving."
One study looked at the distraction caused by drivers’ voice commands to their smartphones; the other, by voice commands to the car’s in-vehicle infotainment system. A researcher in the vehicle recorded distraction time as subjects drove around Salt Lake City neighborhoods at 25 mph or less while using voice commands to do such things as call contacts.
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The researchers found that all the systems studied increased mental distraction to “potentially unsafe levels.”
On the smartphone front, Apple’s Siri and Google Now were rated “highly distracting,” while Microsoft’s Cortana rated “highly to very highly distracting.” As for in-vehicle systems, three were rated as “moderately distracting,” six as “highly distracting” and the system in the 2015 Mazda 6 as “very highly distracting.”
The biggest surprise was that drivers could be distracted for as long as 27 seconds after disconnecting from the “highly distracting” voice-command systems. At 25 mph, that’s enough time to cover the length of three football fields before regaining full attention, the researchers said.
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According to the National Highway Transportation Safety Administration, more than 3,100 people were killed and 424,000 injured in crashes involving distracted drivers in 2013.
University of Utah psychology professor David Strayer, senior author of the two new studies, suggests that people should generally refrain from using voice commands while driving – and definitely not use it for such things as making a call or sending a text.
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“If you are going to use these systems, use them to support the primary task of driving – like for navigation or to change the radio or temperature – and keep the interaction short,” he said.