Why Can't We Walk And Wear Google Glass At The Same Time?

New research explains why such a seemingly simple task is so hard to do.

The era of distracted walking is certainly upon us. Dividing attention between cell phone and sidewalk leaves an estimated 1,500 people a year in the hospital with an embarrassing story to tell. Controlled experiments have found that pedestrians using a phone recall less about their surroundings than other walkers do—with some people so zoned out that they fail to spot a unicycling clown.

Lately any discussion of distracted walking has centered on whether Google Glass will help or hurt the situation. On one hand, the device's very design was supposed to free our eyes to look forward. On the other hand, looking isn't seeing, and some cognitive scientists worry that our inability to see a device and the world around us at the same time could have "potentially dangerous consequences."

Most of the evidence framing this debate has been based on cell phone use. Psychologists have shown quite clearly that people have a hard time concentrating on other tasks, such as driving, while they're on their cell phones. But that comparison is problematic. People will interact with Glass in a much more visual way than they do with their phones. What we need is a study of people walking and considering their visual displays at the same time.

Image: Thomas La Mela via Shutterstock

You don't need Google Glass to see where this one's going. A research team led by behavioral scientist Terhi Mustonen of the University of Helsinki, in Finland, recently designed a study that examines walking and head-mounted displays—the technical name for Glass-type technology. The work was published online earlier this month in the Journal of Experimental Psychology: Applied.

Mustonen and collaborators recruited two dozen participants to partake in the study. The researchers equipped them with a head-mounted display called the Shimadzu Data Glass 2. It may have lacked the alliterative ring of Google Glass, but the apparatus had similar technological perks.

The participants used the head display to perform two types of tasks. One was a memory task that asked test participants to detect when a repeat number appeared in a series. The other was a visual task that had them detect the appearance of a rectangle in a series of squares. Participants performed these while sitting down and again while walking a taped path in a hallway. (The hall was closed off, for safety's sake.)

Sitting down, the tasks weren't too tough. The trouble began when participants started walking. Once ambulatory, the participants did a little worse on the memory task and much worse on the visual task—missing 20% more rectangles and triggering 10% more false alarms.

Image: Flickr user Aaron Anderer

Walking itself became rather hard. Participants slowed down and strayed from the taped hallway path while using the head display to do the simple memory task (spotting a back-to-back repeat in the series). During an advanced memory task (spotting a repeat number from two back) as well as the visual task, their walking speed and performance suffered even more.

"It is extremely difficult to process information from these two sources—the environment and the display—at the same time," Mustonen tells Co.Design.

So why is it so difficult to walk and Glass at the same time? Part of the answer may be that walking requires some actual brainpower despite how automatic it feels. If that were the whole answer, though, we would expect people to do poorly at any display task while walking. In fact, participants did much worse at the visual one than the memory one.

For that reason, the researchers suspect that the brain of someone using Glass might be competing with itself for certain cognitive resources. During the visual task of spotting rectangles, for instance, attention might have been split between seeing where to walk and watching the series of squares change shape. Using our limited visual capacity for two simultaneous visual tasks may, in effect, make us worse at each.

"When concentrating on the [head-mounted display], walking gets more difficult," says Mustonen. "When guiding the gait, performance in the HMD task suffers."

The experiment has some limitations. The most obvious is that people don't typically follow a taped path when they're walking. Then again, one could argue that navigating a crowded sidewalk is equally difficult—so maybe call that a wash. It's also worth wondering whether these experimental games are comparable to the real tasks people will use Glass to perform.

Still, the research suggests the rise of inattentive walking has only begun. Designers, lawmakers, and manners mavens can use this type of work to improve, regulate, and critique the technology (Mustonen, for one, cautions Glass-wearing walkers to be very careful in crowded places). It's not at all reasonable to outlaw Glass, as some have suggested, but appreciating its peculiar brand of distraction is the responsible thing to do—if not for ourselves, then at least for the legion of unicycling clowns.

[Image: Flickr user Lubomir Panak]

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  • My question would be "Does Glass better handle the 'spot a unicycling clown' task than existing mobile devices?" If yes, it's definitely better (at least until we come up with something else which is much better); don't you think?

  • Gary White

    The fundamental flaw in this study is that it's assuming that data processing (via the display) is the priority task whereas google glass and other such prototypes, much like heads up displays already found in aeroplanes, cars, etc. subordinates the data processing task (to provide feedback, report or record data pertinent to) navigation of a person or other entity in space and over time.
    Anyone concentrating on a device as the study suggests would obviously make the same errors as found in the study, as we are all already well aware happens when drivers phone, text or otherwise give most of the attention to a device instead of their environment

  • Phunken

    This just look tacky, same coolness as those bluetooth handsfree ear piece that u see middle age men wear walking around shopping centre for no reason...

  • teddy70

    I'm sure Google is doing plenty of testing around this and the internal testers and current Glass explorers have better cognitive adaptability to handle a random situation. My fear are those consumers that will throw Glass on credit cause it looks "sic" and yet have trouble naming the capital of Washington state. (No it's not DC).
    Bluetooth ear pieces were a cool fad for a time too until people realized it wasn't so cool talking to yourself. <-Raise phone-> OK Google / Siri, reserve seats for 6:30pm @ Ruth Chris and show times & locations for Thor 2 after 9pm. <-Lower Phone-> Put R&D into making that happen!

  • HuskyandSushi

    Saying we can't is like saying we can't cook and listen to music at the same time. Don't write such a bogus headline, it makes the entire article look ridiculous.

  • Rob Grant

    ridiculous or not, it clearly got your attention, and that in the end is the bigger objective.

  • Aziz

    After doing a quick Google search to see what the Shimadzu Data Glass 2 looks like, it would make sense that people's visual data is impaired; it seems that the device covers up one entire eye. I don't think it's fair to compare Shimadzu's LCD eyepatch to the Google Glass, which is not only clear, but also supposed to be worn to be in the corner of your field of vision, so as to not hinder what you see. I think this distinction makes the purpose of this article fall apart: The psychological study's purpose is to see what happens when you're supposed to try and focus on two stimuli at once, but Google Glass was never designed to be something you focus on.

    Unlike the Shimadzu device used in the study, Google Glass's screen is teeny, taking up little space in your field of vision, and for a good reason: it isn't meant to be looked at for long periods of time. The purpose of Glass is for your to take care of what you want to do quicker, and get back to focusing on walking on the taped path in front of you, not to sit down and play spot-the-rectangle in the corner of your eye. The results of this study can apply to cell phones and other devices where you are forced to multitask for extended periods of time, but Glass is built around short, simple interactions, so it would be wrong to correlate what's happening in that study with what a Glass user might experience. Just because they're both head-mounted displays doesn't mean they operate in the same way (I think Google's interaction designers would like to have a word with you, if you agree).

    To answer the question in the title of the article: it's very, VERY easy to walk and use Google Glass at the same time, because unlike when you're walking and typing out 140 characters on your cell phone screen, which, lacking physical buttons, you have to watch carefully, Google Glass keeps your eyes on the road and helps you get those things out of the way. You're not splitting up your attention between two things, you're going 90-10.

    source: I am a Google Glass explorer and can walk and use Glass at the same time.

  • Robert Vorthman

    Headline is misleading. One CAN walk while wearing Glass. The difficulty comes with USING Glass while walking. I have worn Glass everyday for the past six months. This does not prevent me from walking. Reading a text while walking is difficult because your vision is focused on text not your surrounding, but reading texts is a small portion of one's day that does not prevent you from walking all other times of the day. Some of Glass's functions do not require one's vision at all. "ok glass, get directions to home" or "ok glass, google what is the high temperature tomorrow?" can be easily dictated without the need for visual confirmation because Glass's bone conduction audio chimes to confirm your input, or speaks the high temperature. These simple tasks are very easy to perform while walking, I do it all the time, it is the strength of Glass. The same can not be said for a hand-held mobile device. My opinion is that the transition from hand-held mobiles to wearables will decrease distracted walking accidents. Google Glass adoption should be encouraged, not outlawed.

  • Federico Estrada

    Can it just be that people need to learn how to use glass while walking, and that learning may time a user considerable time?

  • Michelle C. Torres-Grant

    That's exactly what I was thinking. I'm an instrumented rated private pilot. Safely piloting a plane with no visual reference (especially during inclement weather) by no means comes naturally and requires training, skill, and practice. It would be a highly dangerous endeavor otherwise. Since our technological society is gravitating toward incorporating devices into our daily lives it seems like training for new skills need to be developed. One can't just plop on a revolutionary device and expect for all to instantly work well. A period of learning and adaptation would be normal.