CBS News
06-14-06
This Is Your Brain Online
By CBSNews.com’s Amy Sara Clark.
The high school sophomore who stays up all night adding to her blog. The 14year-old who plays "Warcraft" for 12 hours at a stretch. The honors student who
says she has no problem writing her English essay while IMing with her boyfriend
and compiling iTunes play lists. Teens will swear up and down that the
technology they won't turn off is harmless fun.
But what if they're wrong?
Only this much is certain: Teens are spending a lot of time hooked up — an
average of 61⁄2 hours a day, according to a survey by the Kaiser Family
Foundation. Parents, researchers, and educators are trying to figure out what all
these hours plugged in are doing to their brains.
The Teen Brain As Construction Site
When considering whether damage is actually being done, the first thing to
understand is that the teenage brain is an unfinished product, explains David
Walsh, a psychologist and author of “Why Do They Act That Way? A Survival
Guide to the Adolescent Brain for You and Your Teen.” The brain continues to
develop in spurts until we're about 25 — something car insurance companies
figured out a long time ago, and which you may have noticed when your rates
dropped after your 25th birthday.
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"Experiences that have the greatest impact on the wiring of the brain are those
that happen during the brain's growth spurts," he says. During those spurts, the
nerve endings grow rapidly, a process called blossoming. During that time, the
cells that fire strengthen networks. The ones that don’t die back — it's called
pruning.
Say a 2-year-old has chronic, untreated ear infections. Because his auditory
functioning is being wired then, the child could end up with permanent hearing
problems.
In the teenage years, says Walsh, one of the major circuits that's developing is
the prefrontal cortex. "The circuits that are under construction during the teen
years have to do with impulse control, management of aggression, emotional
regulation, self regulation — a lot of 'executive functions' of the brain,” he says.
This might explain why your teen might suddenly to storm out during breakfast or
pick fights at school.
Try our interactive to discover what each part of the brain does, and when in
life these areas are wired. Click here.
It's also the reason teenagers are famous for having to pull all-nighters, not
thinking through the consequences of downloading porn onto mom's computer,
or piercing their tongues. That's because the prefrontal cortex also handles
planning, reasoning and social skills, says Jordan Grafman, who heads the
cognitive neuroscience section at the National Institute of Neurological Disorders
and Stroke. "It's what makes us human," he says — and because it's still
developing, "it's very susceptible to trends and changes that happen during the
adolescent years."
Doing Too Much?
Perhaps this sounds familiar: Your daughter says she's doing her homework, but
you keep hearing her IM chime. She swears she "only spent five minutes"
updating her blog. . Those Mariah Carey songs she's downloading? That doesn't
take any time at all.
Teens may think they’re just taking little breaks, but David Meyer, a psychologist
who directs the Brain, Cognition, and Action Laboratory at the University of
Michigan, says they have no idea how much time they're really losing.
"I think there's a lot of mythology out there about how great multitasking is and
that it's the sexy thing," Meyer says. He compares the image of the teen who can
simultaneously IM with five friends while doing his homework with the Marlboro
Man of the mid 20th century. "It's almost like smoking was in the ’50s and ’60s,"
he says. "It's a bunch of hype."
That’s because multitaskers don't just lose the minutes they spend on sites such
as Facebook; they also lose time getting reoriented with each interruption, says
Meyer, whose lab has conducted experiments on multitasking for more than a
decade. That means the homework itself can take between 25 and 400 percent
longer depending on the complexity and similarity of the tasks.
Similarity? Yes. It turns out the worst kind of multitasking is between two related
tasks, because they use the same parts of the brain. It’s better, Meyer says, to
switch from math to piano than, say, history to English.
That's why it's possible to fold laundry while listening to the stock report on the
radio, he says. "They're relying on different kinds of information processing," he
says, noting that the folding is a more automated task.
So how about talking on a cell phone and driving? While these may seem like
different tasks, they both use the "talking" areas of the brain, Meyer says. Say
you're driving in heavy traffic, he says. "You’re reading signs and thinking what to
do next. All this is talking to yourself."
Grafman, from the NIH, says his problem with multitasking goes beyond
concerns about safety or inefficiency.
"If you're constantly shifting around between tasks, then it's likely you can
actually get pretty good at learning visual motor requirements for that shifting," he
says. "But what does that cost you in terms of depth of knowledge?”
“These are frivolous, leisure time activities” he says, adding that he’d “love to
compete against those kids for jobs or anything else they’re not going to have the
knowledge.”
It’s not just teens that need limits on media use. Find out why pediatricians say
too much screen time — even if it's educational — can be harmful to a child.
Click here.
'Grand Theft Auto' Meets Real Life
Research on how technology affects the brain is still in its infancy. But one of the
more studied areas is video games, especially the violent ones.
"What happens when a teen spends a lot of time playing violent videogames is
the aggression center of brain activates but the emotional regulation center of
brain deactivates," says teen brain specialist Walsh, who also directs the
National Institute on Media and the Family. "Exactly the combination that we
would not want to see."
Aggression researcher Bruce Bartholow adds that hundreds of studies have
shown that people who are exposed to media violence become more aggressive.
Bartholow, a psychologist at the University of Missouri, likens the state of
research to that of tobacco research in the '50s and '60s. The link between
smoking and cancer was apparent, he says, but "while scientific evidence was
mounting suggesting a link, the nicotine industry consistently and loudly
protested that the evidence was still unclear."
Bartholow recently finished a study that found young men who played a lot of
violent video games were more aggressive and less sensitive to violence than
those that played fewer violent games. In the study, he questioned them about
on how often they played violent video games and then gave them two tests. In
the first test, they were shown pictures of violent scenes, such as a man holding
a knife to a woman's throat, and their brains' responses to the photos was
measured. Bartholow found that the brain waves of the frequent game players
showed less response than the ones who played less often.
In the second test, the men were told they were testing their reaction times
against other participants, but they were really competing against a computer.
When they won, they were given the chance the chance to blast their
"opponents" with noise. The men who played more violent video games blasted
their opponent with louder noises for longer durations then the men who played
for fewer hours.
And these effects, the study found, didn't fade away a few minutes after turning
off the PlayStation. "This effect is cumulative over time as people are playing
these games on their own," he says. "It’s not just a short-term lab effect."
A study in Japan found that even non-violent games may increase aggression
when played too often. Ryuta Kawashima at Tohoku University, found that
excessive game playing may stunt development of the frontal lobes — including
the cerebral cortex and its impulse control functions. Kawashima compared the
brain activity of teens playing Nintendo games with that of teens doing arithmetic.
He found that the Nintendo group only used the parts of the brain associated with
vision and movement, while the math group had activity not only in the vision and
movement areas, but throughout the frontal lobe — including the areas
associated with learning, emotion, memory and impulse control. Kawashima
argues that the study shows that teens who play video games at the expense of
other activities, like math, reading aloud, or even just socializing or playing
outside, will stunt their prefrontal cortex development end up more violent.
Other studies have shown that video games can be addictive, says Walsh. "One
out of seven develop all of the behavioral traits of a chemical addiction," he says,
such as lying about time spent playing, craving the game when they're not
playing and letting game playing get in the way of personal relationships.
These are the kinds of questions that new methods of looking at the brain in
action may be able to answer. But it's clear the answers will be complicated.
For example, potential ill effects of violence in video games that doesn't mean
that they aren't educational or skill-building, argues Steven Johnson, author of
"Everything Bad is Good For You."
Take one of the very worst of the worst — and most popular — video games: the
"Grand Theft Auto" series. This series gives players the opportunity to massacre
police offices with chainsaws and kill prostitutes for fun. It has such a reputation
for violence, in fact, that last year the families of two murdered police personnel
filed a suit against the game's makers, claiming that it led a teen to murder two
police department workers by hardwiring his brain toward violent scenarios.
"Kids are psychologically rehearsing for theft," says Walsh. But Johnson argues
that playing the game teaches such skills as problem solving, resource
management, identifying patterns and planning.
Eugene Fiume, a computer scientist at the University of Toronto, points out that
games are moving away from the "single shooter" model to multi-player
collaborative games that allow much more room for creativity and cooperation.
In fact, a study at Cornell University suggests that IQs have been going up in
recent decades because of computers, video games, television and the Internet.
According to this study, today's teens' scores are about 25 points higher than
their grandparents and 15 points higher than their parents.
There are plenty of studies that show that video games, even violent ones, can
improve visual and motor skills — useful for athletics, driving, and the military.
And psychologists Mike Posner and Mary K. Rothbart at the University of
Oregon, found that specially designed games can even improve impulse control
in children.
"The real take-home message for me," says Craig Anderson, a psychologist
who researches the effects of media violence at Iowa State University, "is
that a well-constructed video game is an excellent teaching tool. But what it
teaches depends on the content of the game."
GenTech Angst Overblown?
Fifteen-year-old Cassandra Celestin wants you to remember that not every teen
fits the GenTech stereotype. "We’re not just some idle generation sitting at our
desks and staring into cyberspace," she says.
Her favorite (and only) videogame is the educational "HangAroo," which seems
to combine "Wheel of Fortune" with an angry kangaroo. She and her best friend
both gave up IMing because it was too distracting. "I just found I don't have time
with high school and all," she says.
She says she and her friends much prefer hanging out to chatting online. "I think
we've come to the age now where we just want to come out and see each other,"
she says.
So perhaps parents should stop worrying, says Megan Boler, who teaches
education and media studies at the University of Toronto.
"Every new era of technology causes social panics," she wrote via e-mail. "Teen
tech overload may turn out to have some negatives for cognitive development.
On the other hand, the Internet is less passive than the television or radio adults
grew up with, and many of these new forms of media are encouraging self
expression through blogs and Web pages." The popularity of blogs, in fact, may
breed a generation of particularly active citizens who use the Internet for
grassroots organizing and are used to routinely voicing their political opinions
through blogging.
Kaveri Subrahmanyam, who teaches psychology at California State University in
Los Angeles, agrees that these new forms of technology have benefits. Teens
who don't fit in can use it to meet others like themselves, and teens can use it to
organize extracurricular events.
Example: A recent study by the Kaiser Family Foundation found that 8- to 18year-olds who spent the most time hooked up also spent the most time doing
non-media activities.
"People like to think of the Internet as the Big Bad Wolf," says Subrahmanyam.
"But it's almost like they're using the media to boost whatever else they're doing."