Brain Development in a Hyper-Tech World

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Brain Development in a Hyper-Tech World
By Brenda Patoine
BRIEFING PAPER
Ann Whitman
(212)223-4040
awhitman@dana.org
Johanna Goldberg
(212) 223-4040
jgoldberg@dana.org
Brain Development in a Hyper-Tech World
From tweens to 20-somethings, students are heading back to school this year equipped
with the latest electronic gadgets and high-tech accessories. Today’s youth, the most technosavvy generation yet, have grown up on the computer and Internet and have fully embraced
the virtual world, with its emphasis on instant, constant information and communication. They
have practically adopted iPod headsets and cell phones as appendages, often to the bafflement
of older generations.
In the face of this nonstop barrage of technology-induced stimulation, a question on
the minds of many parents, educators and scientists is: how is this affecting young brains? The
question is an important one, and from a scientific standpoint, reasonable to ask given what is
known about the developing brain.
A central tenet of neuroscience, for example, is that the brain continues to develop its
“wiring diagram” at least well into a person’s 20s. The frontal lobes, regions critical to high-level
cognitive skills such as judgment, executive control, and emotional regulation, are the last to
fully develop. It is also well accepted that during this extended developmental period, the brain
is highly adaptable to and influenced by external environmental circumstances. Might the
perpetual bath of technology-driven information and sensory overload impact the stilldeveloping brain in some way?
“There are a lot of things we’ve learned about fundamental principles of brain
development and interactions with the environment and so forth that one can reasonably
hypothesize about what the effects might be,” said Michael Friedlander, head of neuroscience at
Baylor College of Medicine and a member of the Dana Alliance for Brain Initiatives. “But for the
most part, the data aren’t there yet. In terms of actual science investigating people who are
using these technologies – the kind of experiments and hard data that most neuroscientists
would like to collect – it’s pretty thin.”
Given that reality, he added: “The best we can do at this point is look at a lot of the
science that has been done in much more controlled settings and try to extrapolate that to the
real world of kids interacting with these technologies.”
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A Cautionary Flag
While acknowledging that the dearth of data makes it impossible to know what’s going
on for sure, a few prominent neuroscientists are raising a cautionary flag about the possible
long-term consequences of technology overload.
Among them is Dana Alliance member Jordan Grafman, chief of cognitive neuroscience
at the National Institute of Neurological Disorders and Stroke. “In general, technology can be
good [for children’s cognitive development] if it is used judiciously,” Grafman said. “But if it is
used in a nonjudicious fashion, it will shape the brain in what I think will actually be a negative
way.”
The problem is that judicious thinking is among the frontal-lobe skills that are still
developing way past the teenage years. In the meantime, the pull of technology is capturing
kids at an ever earlier age, when they are not generally able to step back and decide what’s
appropriate or necessary, or how much is too much. The outcome, Grafman fears, will be a
generation marked by “laziness of thinking.”
“A lot of what is appealing about all these types of instant communications is that they
are fast,” he said. “Fast is not equated with deliberation. So I think they can produce a
tendency toward shallow thinking. It’s not going to turn off the brain to thinking deeply and
thoughtfully about things, but it is going to make that a little bit more difficult to do.”
Multitasking Taxes the Brain
One area where the research is particularly strong is what is popularly known as
multitasking. Plugged-in kids have gained a reputation for being masters at toggling between,
say, a homework assignment and instant-messaging classmates, downloading music and
texting on the cell phone, surfing the Internet while updating Facebook pages, and so on.
A 2006 survey by the Kaiser Family Foundation1 found that middle and high school
students spend an average of 6.5 hours a day hooked up to computers or otherwise using
electronic devices, and more than a quarter of them are routinely using several types of media
at once. It also found that when teens are “studying” at the computer, two-thirds of the time
they are also doing something else.
“Children’s rooms are now almost pathogenic because they have so many distractions,”
said Dana Alliance member Martha Bridge Denckla, a neuroscientist at Kennedy Krieger
Institute and Johns Hopkins who studies attention deficit disorders in kids. “I think the most
devastating thing that has happened is giving a child a room with a computer in it – you think
you’re being a good parent by doing so. Well, a funny thing can happen on the way to the
homework.”
While the common perception is that multitasking saves time, enabling one to get
things done faster and better, the evidence suggests quite the opposite. It is clear from a large
body of solid scientific research conducted over the past two decades that dividing the brain’s
attention between two or more tasks simultaneously has costs, both in performance and time.
Several independent research groups have reported evidence that, at the level of
neural systems, multitasking actually entails rapid switching from one task to another. Each
switch exacts a toll, at least doubling the time it takes to complete a task and decreasing both
the level of performance and the ability to recall what you were doing later on. Study after
study has found that multitasking degrades the quality of learning.2
Among the leading researchers who have published heavily in this area are Paul Dux,
Vanderbilt University; Marcel Just, Carnegie Mellon University; David Meyer, University of
Michigan; Hal Pashler, University of California at San Diego; Russell Poldrack, University of
California at Los Angeles, and David Strayer, University of Utah.
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The bulk of the evidence comes from laboratory-based studies, using carefully
designed experiments in controlled settings to tease apart the brain mechanisms underlying
task-switching and its costs – and much of it has been conducted with 20-somethings. As such,
Grafman said, the research “relates very nicely to multitasking on computers” and is highly
relevant to the developing brain.
Strayer’s work has extended the research to real-world situations such as driving while
talking on a cell phone. He has found significantly lower reaction times and a two-fold increase
in rear-end accidents among both teenage and older drivers who were simultaneously engaged
in cell-phone conversations.3 In one study, Strayer and colleagues concluded that “the
impairments associated with using a cell phone while driving can be as profound as those
associated with driving while drunk.”3
“The bottom line is that if you try to do more than one thing at the same time, you’re
going to have a decrement in performance,” said Grafman. “This has been shown over and over
again, and it has not changed from the last generation of young people to today’s young
people.”
He added: “I think that one of the big trade-offs between multitasking and ‘unitasking,’
as I call it, is that in multitasking, the opportunity for deeper thinking, for deliberation, or for
abstract thinking is much more limited. You have to rely more on surface-level information, and
that is not a good recipe for creativity or invention.”
‘Mile Wide, Inch Deep’ Knowledge?
Friedlander echoed this sentiment: “If a child is doing homework while on the computer
engaged in chat rooms, or listening to iTunes and so forth, I do think there is a risk that there
will never be enough depth and time spent on any one component to go as deep or as far as
you might have. You might satisfactorily get all these things done, but the quality of the work
or of the communication may not reach the level that it could have had it been given one’s full
attention. There’s a risk of being a mile wide and an inch deep.”
Grafman emphasized that the issues – while relevant to people of all ages – are
particularly of concern to children’s whose brains are still developing. “When teens are learning
routines – whatever those routines are – the dominant routine is going to play a bigger role in
how their brain develops and what kinds of strategies are stored,” he said. If they are
constantly toggling between homework and instant messaging and videos, they may get really
good at toggling, but as Grafman pointed out, “that does not necessarily equate to being a
smarter person.”
Social Development in the Facebook Age
Another area of concern in today’s digital world is the impact of electronic
communication on social interactions. The hard science is slim, but experts say there is reason
to believe that when the bulk of a young person’s interactions with others is done electronically
at the expense of face-to-face communication, social development may be affected.
So-called “social cognition,” which encompasses such things as the ability to form
impressions of others, make inferences about their intentions, gauge their emotional reactions
and adjust your actions accordingly, is another complex skill that relies on the pre-frontal
cortex, the brain’s forward-most and last-to-develop region. Like other high-level cognitive
functions, mastery of these skills requires practice. “If you don’t have sufficient in-person
practice, that has got to be handicapping you in some way,” said Grafman.
Real-world interactions entail what Friedlander calls “broadband communication,” a
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term borrowed from the digital world. “So much of what we’re conveying to each other comes
from the intonation of our voice, the looks, the facial expression, the body language, the pauses
– all those subtle cues that go into communication. Kids who are spending all of their time
interacting through this cyber world are very likely to not have the opportunity to develop sets
of skills that are innate and important to the human brain in terms of what we call social
cognition.”
Friedlander also wonders if over-reliance on electronic interactions, which are so often
marked by unnatural delays, even minute ones as in cell-phone conversations, might wire
developing brains to a different baseline set-point for temporal processing – how time is
interpreted.
“We don’t really know how that will affect kids or if it will have long-term effects, but I
think it supports the notion that one needs to be careful to not become totally immersed in the
cyber world, because it may be a little more awkward interacting with real living people in real
situations where those timing delays are somewhat different,” Freidlander said.
How Much is Too Much?
The information explosion brought about by the Internet and other modern
technological tools has undeniably had positive influences on society. “These are enabling
technologies,” said Friedlander. “I think their greatest power lies in their ability to enable people
to reach out to a world that is much greater than what any child is likely to get in their home or
school environment. That’s all good and positive.”
The trick, he said, is knowing where to draw the line. “It gets down to a quantitative
question: how much is too much? That’s where the rubber really meets the road for most
people, and that is a really tough question to answer.”
The responsibility for making such decisions often falls on parents, but they may not be
equipped, able, or willing to do so. “We always hear the same thing, that it’s up to parents to
control the use of these things and teach kids how to manage it all,” said Grafman. “But in
order for them to do this, they have to understand better themselves what they are creating
with their children. Many parents today just say, ‘here’s your computer, put it in your room and
do your homework on it,’ and that’s the last they see of the kid. If that’s the case, how much
are kids going to listen?”
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The Dana Foundation is a private philanthropic organization with particular interests in brain
science, immunology, and arts education.
Written by Brenda Patoine (BPatoine@aol.com), a freelance science writer who has been
covering neuroscience research for more than 15 years.
Kaiser Family Foundation, Program for the Study of Media and Health. “Media Multitasking
Among American Youth: Prevalence, Predictors and Pairings.” Released Dec. 12,
2006. http://kff.org/entmedia/7592.cfm (Accessed Aug. 15, 2008)
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2
See for example:
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· Foerde K, Knowlton BJ, Poldrack RA. Modulation of competing memory systems by
distraction. Proc Natl Acad Sci USA 2006;103(31):11778-83.
· Dux PE, Ivanoff J, Asplund CL, Marois R. Isolation of a central bottleneck of information
processing with time-resolved fMRI. Neuron 2006;52:1109-21.
· Rohrer D, Pashler HF. Concurrent task effects on memory retrieval. Psychol Bull Rev
2003;101(4):96-103.
Strayer DL, Drews FA. Profiles in driver distraction: effects of cell phone conversations on
younger and older drivers. Hum Factors 2004;46(4):640-9.
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Strayer DL, Drews FA, Crouch DJ. A comparison of the cell phone driver and the drunk
driver. Hum Factors 2006;48(2):381-91.
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8/2008
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