Up to 27 seconds of inattention after talking to your car or smartphone

October 22, 2015
A University of Utah research assistant introduces a participant in new distracted driving studies to specialdevices designed to gauge mental distraction during road tests. Credit: AAA Foundation for Traffic Safety

If you think it is okay to talk to your car infotainment system or smartphone while driving or even when stopped at a red light, think again. It takes up to 27 seconds to regain full attention after issuing voice commands, University of Utah researchers found in a pair of new studies for the AAA Foundation for Traffic Safety.

One of the studies showed that it is highly distracting to use hands-free to dial phone numbers, call contacts, change music and send texts with Microsoft Cortana, Apple Siri and Google Now smartphone personal assistants, though Google Now was a bit less distracting than the others.

The other study examined voice-dialing, voice-contact calling and music selection using in-vehicle information or "infotainment" systems in 10 model-year 2015 vehicles. Three were rated as moderately distracting, six as highly distracting and the system in the 2015 Mazda 6 as very highly distracting.

"Just because these systems are in the car doesn't mean it's a good idea to use them while you are driving," says University of Utah psychology professor David Strayer, senior author of the two new studies. "They are very distracting, very error prone and very frustrating to use. Far too many people are dying because of on the roadway, and putting another source of distraction at the fingertips of drivers is not a good idea. It's better not to use them when you are driving."

The research also found that, contrary to what some may believe, practice with voice-recognition systems doesn't eliminate distraction. The studies also showed older drivers - those most likely to buy autos with infotainment systems - are much more distracted than younger drivers when giving voice commands.

But the most surprising finding was that a driver traveling only 25 mph continues to be distracted for up to 27 seconds after disconnecting from highly distracting phone and car voice-command systems, and up to 15 seconds after disconnecting from the moderately distracting systems.

The 27 seconds means a driver traveling 25 mph would cover the length of three football fields before regaining full attention.

"Most people think, 'I hang up and I'm good to go,'" Strayer says. "But that's just not the case. We see it takes a surprisingly long time to come back to full attention. Even sending a short text message can cause almost another 30 seconds of impaired attention."

"The voice-command technology isn't ready," says Joel Cooper, a University of Utah research assistant professor of psychology and a co-author of the new studies. "It's in the cars and is billed as a safe alternative to manual interactions with your car, but the voice systems simply don't work well enough."

"Many of these systems have been put into cars with a voice-recognition system to control entertainment: Facebook, Twitter, Instagram, Snapchat, Facetime, etc. We now are trying to entertain the driver rather than keep the driver's attention on the road."

In 2013, 3,154 people died and 424,000 others were injured in motor vehicle crashes on U.S. roads involving , says the U.S. Department of Transportation.

The new AAA reports urge that voice activated, in-vehicle information systems "ought not to be used indiscriminately" while driving, and advise that "caution is warranted" in smart-phone use while driving.

The studies are fifth and sixth since 2013 by University of Utah psychologists and funded by the AAA Foundation for Traffic Safety. AAA formerly was known as the American Automobile Association. Strayer and Cooper ran the studies with Utah psychology doctoral students Joanna Turrill, James Coleman and Rachel Hopman.

This graphic shows the mental distraction scores of three smartphone personal assistants and 10 in-vehicle infotainment systems for using voice commands in cars to call contacts, dial phone numbers or change music. The smartphone assistants' scores were 0.3 points higher than shown if a driver also sent text messages using them. Credit: AAA Foundation for Traffic Safety

The ratings: In-car systems and smartphone assistants are distracting

The previous Utah-AAA studies devised a five-point scale: 1 mild distraction, 2 moderate distraction, 3 high distraction, 4 very high distraction and 5 maximum distraction. Those studies showed cellphone calls were moderately distracting, with scores of 2.5 for hand-held calls and 2.3 for hands-free calls. Listening to a book on tape rated mild distraction at 1.7. Listening to the radio rated 1.2.

One of the new studies found mild distraction for in-vehicle information systems in the Chevy Equinox with MyLink (2.4), Buick Lacrosse with IntelliLink (2.4) and Toyota 4Runner with Entune (2.9).

High distraction systems were the Ford Taurus with Sync MyFord Touch (3.1), Chevy Malibu with MyLink (3.4), Volkswagen Passat with Car-Net (3.5), Nissan Altima with Nissan Connect (3.7), Chrysler 200c with Uconnect (3.8) and Hyundai Sonata with Blue Link (3.8). The Mazda 6's Connect system rated very highly distracting (4.6).

In some cases, the same voice-command system (like Chevy MyLink) got different distraction scores in different models - something the researchers speculate is due to varying amounts of road noise and use of different in-vehicle microphones.

The second new study found all three major smartphone personal assistants either highly or very highly distracting. Two scores were given to each voice-based system: A lower number for using voice commands only to make calls or change music when driving - the same tasks done with the in-car systems - and a higher number that also included using smartphones to send texts by voice commands.

Google Now rated highly distracting (3.0, 3.3), as did Apple Siri (3.4, 3.7), while Microsoft Cortana rated highly to very highly distracting (3.8, 4.1).

Strayer says of both in-car information systems and smartphone personal assistants: "These systems are often very difficult to use, especially if you're just trying to entertain yourself. ... The vast majority of people we tested ended up being frustrated by the complexity and error-prone nature of the systems."

How the studies were conducted

The new studies were conducted with participants driving the various cars at 25 mph or less around a 2.7-mile route in Salt Lake City's Avenues neighborhood as they used voice-commands to dial numbers, call contacts and tune the radio using in-car systems, and to dial numbers, call contacts, choose music and text using smartphones.

With researchers in the car, the drivers were tested for the extent of their distraction, even as they kept their eyes on the road and hands on the wheel after hitting a voice-command system button. A head-mounted LED light flashed red every three to five seconds at the edge of a driver's left eye. Drivers pressed a switch attached to a thumb when they saw the light. The researchers measured how voice interactions with a car or smartphone reduced drivers' reaction times and accuracy at seeing the flashing lights. The drivers also completed surveys about their perceived level of distraction, and videos measured how much of the time they kept their eyes on the road, mirrors or dashboard.

The in-vehicle information system study included 257 people and the smartphone personal assistant study had 65 participants, all with no at-fault accidents during the past five years. Unlike the 2013 and 2014 studies, which included primarily people in their 20s, subjects in the new studies ranged in age from 21 to 70.

In the in-car information system study, the researchers did an initial test on the subjects, then let them take the cars home for five days to practice using the systems. Then they returned for reassessment of the mental workload from using the systems.

Strayer personally doesn't even make hands-free cellphone calls while driving. He advises against using voice commands system while driving for purposes such as voice dialing, voice contact calling, surfing the Internet, sending email and text messages, reading email, tweeting or updating Facebook.

"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."

Explore further: Talking to your car can be dangerous, studies say

Related Stories

Hands-free texting still distracting for drivers (Update)

June 12, 2013

Using voice commands to send text messages and emails from behind the wheel, which is marketed as a safer alternative for drivers, actually is more distracting and dangerous than simply talking on a cellphone, a study by ...

GM cars to use Apple voice assistant Siri

November 27, 2012

General Motors said Tuesday it will integrate Apple's voice-activated software Siri in some of its cars next year to allow iPhone users to perform hands-free tasks.

Recommended for you

Swiss unveil stratospheric solar plane

December 7, 2016

Just months after two Swiss pilots completed a historic round-the-world trip in a Sun-powered plane, another Swiss adventurer on Wednesday unveiled a solar plane aimed at reaching the stratosphere.

Solar panels repay their energy 'debt': study

December 6, 2016

The climate-friendly electricity generated by solar panels in the past 40 years has all but cancelled out the polluting energy used to produce them, a study said Tuesday.

Wall-jumping robot is most vertically agile ever built

December 6, 2016

Roboticists at UC Berkeley have designed a small robot that can leap into the air and then spring off a wall, or perform multiple vertical jumps in a row, resulting in the highest robotic vertical jumping agility ever recorded. ...

12 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

Lex Talonis
5 / 5 (1) Oct 22, 2015
There is nothing I have found that produces a more "total disconnect" from reality when using a smart phone, aside from a general IV anasthetic, or similar.

Total oblivion - even on a bicycle at like walking speed, on a country road with no traffic.....

dogbert
3 / 5 (2) Oct 22, 2015
This so called study is just B.S.

A head-mounted LED light flashed red every three to five seconds at the edge of a driver's left eye. Drivers pressed a switch attached to a thumb when they saw the light.


The study added an irritating distraction [flashing red LED] and drivers who were able to ignore the distraction were rated as distracted.
BONK__RS
not rated yet Oct 22, 2015
It's all about the amount of cognitive effort you need to reserve, in order to get the command registered into the stupid computer - you unconsciously build a model of what it can cope with and what it can't, that's where the effort goes.
If you were to do the same test, but instructing a human co-driver to change the radio station, etc etc. - there would be very little distraction. I offer no proof, but it seems obvious to me.
krundoloss
not rated yet Oct 22, 2015
I agree that driving, sending voice commands to your car and trying to pay attention to a flashing red LED is too much for anyone to comfortably handle. It is not a valid test, because most drivers will focus on DRIVING and not on Clicking some button when a light blinks. When you drive, you can switch your attention to full attention in about 1 second. The study appears to be flawed in its conclusions. They should have just had people drive on a safe obstacle course, trying to dodge water balloons or something that is engaging and requires full attention, and measure their performance that way.

I do think that modern cars with Touchscreen interfaces are unsafe. You have to look at a touchscreen. You don't have to look at knobs, buttons and switches. I regularly adjust my car stereo's subwoofer level settings without looking, try that with your fancy touchscreen device. They have no business being in a car if you ask me.
NealWV
1 / 5 (1) Oct 22, 2015
When are we going to quit with this ridiculous cell phone causing accidents crap? There have been inattentive drivers since the car was invented. It's not the phones fault. People who are distracted because of a phone would do the same with anything else such as kids. We aren't going after people who eat, do make-up, and even read like we are with phones. The fact is everyone talks on phones so its obvious that people are going to be in a wreck while operating them. Would everyone feel better if they wrecked because they were spacing out? I've been talking and driving since they came out and the only wreck I had caused by inattention was when I wasn't on the phone.
freeiam
not rated yet Oct 22, 2015
What is interesting is how much the results differ between the test participants.
That could also be an indication of the tests validity.
SuperThunder
1.3 / 5 (4) Oct 22, 2015
This is why the Enterprise D had a thousand people on it even though it could do everything with just one person giving voice commands. "Computer, tea, Earl Grey, hot." *stares at oncoming Romulan ship* "Oh sh-*BOOM*"

Is this somehow connected to the technology itself, or do battlefield commanders also have a post-command reset period?

When are we going to quit with this ridiculous cell phone causing accidents crap?


When you stop texting and driving.
Captain Stumpy
5 / 5 (3) Oct 22, 2015
do battlefield commanders also have a post-command reset period?
@SuperT
short answer: yes

long answer: all soldiers have a post command reset period, usually called a debriefing, but also sometimes called retraining, readjustment or other acronyms (BOHICA comes to mind) .

This can be anywhere from an hour to a few weeks, depending upon circumstances, security levels and exposures. it is common in the military, especially in the combat arms or service jobs that require continued exposure to high risk situations (like Firefighters, cops, ambulance service) to get continued debriefings, as well as psych retraining, etc

SuperThunder
1.8 / 5 (5) Oct 22, 2015
Captain Stumpy, I meant on giving a tactical or situational command. Such as...

"Soldier X do Y" during Situation Z. Is there a period after that, such as with the voice commanded technology, where a return to full attention to Z is 27 seconds away? I was curious if the delay was tied to the people or to the technology. Something more immediate than long term exposure.

Wait, unless the article means that long term exposure to using this technology creates the delay, and my reading comprehension is terrible, which is entirely possible.
Nik_2213
not rated yet Oct 22, 2015
Does this also apply to drivers singing along to LOUD 'driving music' while beating time on the steering wheel ? Or yelling at the talk-show host on their radio ??

IIRC, 'rule of thumb' is that habitually taking your attention off road for more than half-a-sec at a time is ill-advised...

I know many drivers hate motorways because they're *boring* but, surely, the fewer immediate hazards allows you to extend your scan radius, spot potential ijits then 'be not there' ??
Captain Stumpy
5 / 5 (2) Oct 23, 2015
Captain Stumpy, I meant on giving a tactical or situational command. Such as...

"Soldier X do Y" during Situation Z. Is there a period after that, such as with the voice commanded technology, where a return to full attention to Z is 27 seconds away?
@SuperT
no. not intentionally planned.
I was curious if the delay was tied to the people or to the technology
IMHO, i think it is far more likely this is a human issue.
humans can only do one thing at a time. even when "multitasking" the brain focuses primarily on single tasks but switches back and forth or there is partial attention, which makes humans more error prone.
https://en.wikipe...itasking

here is a good book about how the brain makes up it's mind- explains a little about multitasking too...
http://www.amazon...47673139

MR166
5 / 5 (3) Oct 23, 2015
I have a Ford My Snyc Touch system in my car and hate it. Dash control knobs have been replaced with touch sensors and there is no reliable way to manually change setting without taking your eyes off the road and trying to read small print.

Even if you are distracted and not looking at the road for just one second the consequences can be enormous. Voice controls are for the most part a pain in the ass.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.