Pubdate: Sun, 02 Apr 2006
Source: St. Louis Post-Dispatch (MO)
Copyright: 2006 St. Louis Post-Dispatch
Contact:  http://www.stltoday.com/
Details: http://www.mapinc.org/media/418
Author: Tina Hesman Saey, St. Louis Post-Dispatch

DRUG USE CAN DAMAGE THE BRAIN AND LEAD TO ADDICTION

Teenagers who drink, smoke and use drugs can derail their brain
development and set themselves up for lifelong addiction.

And parents who strictly monitor their teens' behavior are one of the
most influential forces preventing kids from using drugs and alcohol.

Now that might not sound like news to you.

But truth is, until recently most of what science has known about
addiction in teenagers has been extrapolated from research in adults.
Now, new brain-imaging studies have shown that the teenage brain is a
rapidly-changing organ and doesn't work the way an adult brain does.
Researchers now believe that drugs and alcohol can disrupt that
massive renovation of the brain during adolescence, making it more
vulnerable to drugs and easier for teens to get addicted.

And scientists say that an addiction that starts early in life is
harder to kick than one that starts later. Nearly half of kids who are
regular drinkers before age 14 will become alcoholics, said Dr.
Danielle Dick, a clinical psychologist and geneticist at Washington
University. That puts early drinkers at three times greater risk of
alcohol addiction than people who wait until age 21 to start drinking,
she said.

Percy Menzies, director of the Assisted Recovery Centers of America,
an addiction treatment center in St. Louis, says that "When people
come to us and say they started drinking as teenagers, we know we have
our work cut out."

Epidemiological studies have shown that most addictions start in
adolescence, said Dr. Nora Volkow, director of the National Institute
on Drug Abuse. And when a teenager's pleasure-chemical systems aren't
fully developed and then get wired to depend on substances for feeling
good, the normal flow of brain chemicals that aid in learning,
decision making and other key processes are often blocked, Volkow said.

Parents are the key

In adults, genetics are more than 50 percent responsible for addiction
to alcohol. So people have long assumed that genes are the biggest
reason kids drink, too.

But new studies of twins in Finland and Missouri showed no evidence
that genetics contributed to alcohol-dependence in 14-year-olds, Dick
said.

Instead, Dick said, parental monitoring is one of the most consistent
predictors of whether teens start using alcohol and other drugs.

And that means more than just having a good relationship with your
kids. A good, warm relationship doesn't mean kids are going to tell
parents what they are doing, or with whom.

"Parents might say, 'Oh, if they were doing that, they'd tell me,' but
the reality is, they probably won't," Dick said. What works is knowing
where children are, who they are with and what they are doing.
Children with the highest level of parental monitoring were less
likely to start drinking or using drugs, Dick said.

For an addiction to take hold, kids must be exposed to addictive
substances. So young adolescents who never have a chance to smoke or
drink avoid stirring up a genetic predisposition to addiction. In a
more permissive environment, genes may rear their heads.

Once teens start to drink or use drugs, the consequences turn severe.
Recent studies show that teens who start using marijuana before they
turn 17 are at higher risk of developing schizophrenia than people who
didn't use or started smoking marijuana later in adolescence or young
adulthood.

Marijuana has often been called a gateway drug, a substance that can
lead to use of more harmful drugs. Most researchers agree that
marijuana doesn't necessarily set up the brain for further addictions,
but does give kids practice in obtaining illicit substances and access
to a subculture where harder drugs are available.

The real gateway drug may be nicotine, experts say. Most kids try
cigarettes before other drugs.

Researchers compared sets of identical twins in which one twin started
smoking before age 17 and the other twin smoked later. Twins who
started smoking before age 17 became addicted to other substances,
such as alcohol or other drugs, more readily than their twins who
waited, Volkow said. Because identical twins have the same genetic
make-up, the addiction of early-smoking twins can't be chalked up to
genetic susceptibility alone, she said.

Cigarette smoking also can disrupt memory and attention, said Dr.
Leslie Jacobsen, a psychiatrist at Yale University. But withdrawal
from cigarettes is also bad, she said.

"Once you're dependent, you're always confronted with a certain amount
of nicotine withdrawal," she said.

"Children get addicted to smoking more quickly than they expect, and
many aren't even aware that they are dependent," she said.

Brain is at risk

Even teens who just binge drink on weekends can hurt their brains,
said Susan F. Tapert, an associate professor of psychiatry at the
University of California San Diego. Her measurements of a
seahorse-shaped part of the brain, called the hippocampus, revealed
that drinkers had shrunken hippocampuses compared with teens who don't
drink. That is important because the hippocampus is one of the regions
of the brain most responsible for learning and memory.

Tapert doesn't see the same dramatic change in the hippocampus of
marijuana smokers.

But that may not matter, Jacobsen said.

"It's not just how the brain looks, but how it works that's
important," she said.

Teens who smoke marijuana - even those who have stopped using for a
month - need to expend much more mental energy to do simple tasks,
Tapert said.

For instance, marijuana smokers retain 5 percent to 10 percent less
information when listening to a story. That difference may not seem
big, but could make the difference between passing or failing a test
in school.

A University of Missouri study of college-age students showed that
chronic binge drinkers make bad decisions in other parts of life.
Researchers at the Midwest Alcoholism Research Center in Columbia
tested 19 and 20-year-olds on a decision-making task involving
gambling risks. People who were chronic binge drinkers more often made
decisions that would put them at high risk for losing money, said
Kenneth J. Sher, director of the center.

The binge drinkers weren't more impulsive or thrill-seeking than their
non-drinking counterparts and they scored similarly on the ACT college
entrance exam. But bad decision making on the gambling test was also
associated with making unwise decisions about drinking in life. The
heaviest drinkers had their first full drink at age 13, and were
bingeing on almost 18 drinks per week by the fall of the their
freshman year in college.

The researchers don't know whether the students are heavy binge
drinkers because they are bad at decision-making or if the alcohol
impairs their ability to make good decisions, Sher said.

Either way, students get set in their ways earlier than many parents
realize, he said.

"Most drinking patterns are set before they get to college," Sher
said.

Parents unwittingly give young teens access to alcohol. Few parents
think to lock up their liquor cabinets, Sher said.

"I think parents are clueless," he said. And many have a strong case
of denial. "They don't think their kids would ever drink."

The concern that some parents have about being hypocritical when
telling their kids not to smoke, drink or use marijuana is misplaced
in light of the data on how drugs affect young brains, Volkow said.

Parents often don't realize that the weed their children are smoking
is far more powerful than the herb kids smoked a decade ago, Volkow
said. The concentration of THC (delta-9-tetrahydrocannabinol) the main
active chemical in marijuana, has risen from 2 percent of the active
ingredients to 14 percent, she said.

As grim as the picture is for teens who use drugs, tobacco or alcohol,
there is some good news. Because the teen brain is still developing,
it may be able to recover from the harm of substance use if teens
clean up their acts.
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MAP posted-by: Derek