Brain,
Interrupted
By
Bob Sullivan and Hugh Thompson | New York Times – Tues, May
7, 2013
Technology has given us many gifts, among them dozens of new ways to
grab our attention. It’s hard to talk to a friend without your phone
buzzing at least once. Odds are high you will check your Twitter feed
or Facebook wall while reading this article. Just try to type a memo at
work without having an e-mail pop up that ruins your train of thought.
But what constitutes distraction? Does the mere possibility that a
phone call or e-mail will soon arrive drain your brain power? And does
distraction matter — do interruptions make us dumber? Quite a bit,
according to new research by Carnegie Mellon University’s
Human-Computer Interaction Lab. There’s a lot of debate among brain
researchers about the impact of gadgets on our brains. Most discussion
has focused on the deleterious effect of multitasking. Early results
show what most of us know implicitly: if you do two things at once,
both efforts suffer.
In fact, multitasking is a misnomer. In most situations, the person
juggling e-mail, text messaging, Facebook and a meeting is really doing
something called “rapid toggling between tasks,” and is engaged in
constant context switching. As economics students know, switching
involves costs. But how much? When a consumer switches banks, or a
company switches suppliers, it’s relatively easy to count the added
expense of the hassle of change. When your brain is switching tasks,
the cost is harder to quantify.
There have been a few efforts to do so: Gloria Mark of the University
of California, Irvine, found that a typical office worker gets only 11
minutes between each interruption, while it takes an average of 25
minutes to return to the original task after an interruption. But there
has been scant research on the quality of work done during these
periods of rapid toggling.
We decided to investigate further, and asked Alessandro Acquisti, a
professor of information technology, and the psychologist Eyal Peer at
Carnegie Mellon to design an experiment to measure the brain power lost
when someone is interrupted. To simulate the pull of an expected
cellphone call or e-mail, we had subjects sit in a lab and perform a
standard cognitive skill test. In the experiment, 136 subjects were
asked to read a short passage and answer questions about it.
There were three groups of subjects; one merely completed the test. The
other two were told they “might be contacted for further instructions”
at any moment via instant message. During an initial test, the second
and third groups were interrupted twice. Then a second test was
administered, but this time, only the second group was interrupted. The
third group awaited an interruption that never came. Let’s call the
three groups Control,
Interrupted and On
High Alert.
We expected the Interrupted group to make some mistakes, but the
results were truly dismal, especially for those who think of themselves
as multitaskers: during this first test, both interrupted groups
answered correctly 20 percent less often than members of the control
group.
In other words, the distraction of an interruption, combined with the
brain drain of preparing for that interruption, made our test takers 20
percent dumber. That’s enough to turn a B-minus student (80 percent)
into a failure (62 percent). But in Part 2 of the experiment, the
results were not as bleak. This time, part of the group was told they
would be interrupted again, but they were actually left alone to focus
on the questions.
Again, the Interrupted group underperformed the control group, but this
time they closed the gap significantly, to a respectable 14 percent.
Dr. Peer said this suggested that people who experience an
interruption, and expect another, can learn to improve how they deal
with it.
But among the On High Alert group, there was a twist. Those who were
warned of an interruption that never came improved by a whopping 43
percent, and even outperformed the control test takers who were left
alone. This unexpected, counterintuitive finding requires further
research, but Dr. Peer thinks there’s a simple explanation:
participants learned from their experience, and their brains adapted.
Somehow, it seems, they marshaled extra brain power to steel themselves
against interruption, or perhaps the potential for interruptions served
as a kind of deadline that helped them focus even better. Clifford
Nass, a Stanford sociologist who conducted some of the first tests on
multitasking, has said that those who can’t resist the lure of doing
two things at once are “suckers for irrelevancy.” There is some
evidence that we’re not just suckers for that new text message, or
addicted to it; it’s actually robbing us of brain power, too. Tweet
about this at your own risk.
What the Carnegie Mellon study shows, however, is that it is possible
to train yourself for distractions, even if you don’t know when they’ll
hit.
Bob Sullivan, a
journalist at NBC News, and Hugh Thompson, a computer scientist and
entrepreneur, are the authors of “The Plateau Effect: Getting From
Stuck to Success.”