You're Teaching My Child What? (11 page)

Enter magnetic resonance imaging (MRI). This technique, invented in the 1970s, produces “exquisitely accurate”
⁵²
images of brain structure without using radiation. Even more exciting, real-time images of the brain at work—doing a math problem, recalling an event, feeling pleasure or fear—were available with the advent of functional MRI (fMRI). With the elimination of health risks, MRI and fMRI permitted observation of healthy children and teens, revolutionizing the study of brain and behavioral development.

For researchers, the biggest surprise came when they looked inside the heads of adolescents. They discovered that brain maturation does not end in early childhood; it simply pauses for some years, only to restart with vigor at the onset of puberty. During the second decade of life and into the third, a period of “explosive growth and restructuring” takes place. There is a “dramatic metamorphosis of the brain,” writes one of the leading developmental psychologists in this young field. “The magnitude of these brain alterations is difficult to fathom.”
⁵³

Think of it as Extreme Makeover: Teen Brain Edition. Due to this massive transformation, adolescence is a period of life with distinct vulnerabilities and opportunities.

We are now certain that the adolescent brain functions differently from an adult's. The importance of this discovery, say some of the country's eminent neurobiologists, should not be understated.
⁵⁴

Dr. Jay Giedd, chief of brain imaging in child psychiatry at the National Institute of Mental Health, has used Magnetic Resonance Imaging (MRI)s to peer into the heads of 1,800 kids, gaining a real-time view of the brain at work.
⁵⁵
He scanned normal volunteers every two years during childhood, adolescence, and sometimes beyond. At first he planned to stop at age eighteen or twenty, but he discovered that was too soon: remodeling of some brain regions continues into the third decade of life. Dr Giedd and others found that an area called the prefrontal cortex (PFC) is the last to mature: it may not completely develop until the mid-twenties. “Avis must have some pretty sophisticated neuroscientists,” he jokes, referring to the company's refusal to rent a car to drivers under the age of twenty-five.

The PFC is located behind the forehead, and is responsible for the executive functions of the brain: judging, reasoning, decision-making, self-evaluation, planning, suppression of impulses, and weighing the consequences of one's decisions. “It allows us to act on the basis of reason,” explains Daniel Weinberger, Director of the Clinical Brain Disorders Laboratory at the NIH.
⁵⁷
The PFC is like the Chief Executive Officer (CEO), and it is the final region to mature. Of course, parents don't need to have their kids' brains scanned to know they're capable of goofy and thoughtless behavior, but it's nice when science confirms what moms and dads have always known.

If the CEO isn't fully on the job yet, how are adolescents at making decisions, especially ones involving risk? That's a critical question: the rates of death, disability and health problems of teens is
200 percent to 300 percent higher
than in children, due primarily to their poor control of behavior and emotion.
⁵⁸
A portion of this burden
is a consequence of sexual activity: pregnancy, sexually transmitted infections, and emotional turmoil. In devising an effective public health response to this crisis, the process of adolescent decision-making
⁵⁹
must be examined.

Again, thanks to the new technology, we have a window through which we can observe, measure, and record the brain at work. The “neurobiology of decision making”
⁶⁰
indicates that making choices relies on at least twelve different brain regions. These areas include cognitive and affective circuits, meaning decisions are based on both thought and emotion.

The PFC is the center of the “thinking” brain, and the amygdala (ah-MIG-di-lah) is a principle structure of the “feeling” brain. These two networks are seen as parallel systems whose integration evolves with time. The emotional system is present early in life; it's fast and mostly automatic—what's often called a gut reaction. The cognitive system develops with age, is slow and deliberate, and sometimes competes with the older system.
⁶¹
It has been suggested that because the emotional system is more mature than the cognitive one in teens, it sometimes contributes more to decision-making, resulting in less-than-optimal choices.
⁶²

Dr. Laurence Steinberg, a nationally recognized expert in adolescent psychology at Temple University, draws a distinction between “cool” and “hot” conditions, referring to the intensity or level of emotion at the time a decision is made.
⁶³
Under “cool” conditions—a hypothetical dilemma in class, for example—a teen might appear to have excellent “executive functions”: in making a choice, he engages in deliberate, logical thinking.
Sure,
he might resolve,
being sexually active is a big decision, so I'll take my time and consider the pros and cons. I'll talk it all over with my “partner,” and we'll discuss STDs and contraceptives. After we make our decision, at the right time, we'll naturally stop everything and properly put on the condom that I'll have had the forethought to get and carry with me.

But “cool” conditions are not the real world. Place the same boy in an unexpected situation, say at an unsupervised party,
⁶⁴
add a cute and
willing girl to the picture, along with peers who are disappearing together into bedrooms, and it's a different story. Functional MRIs tell us that under “hot conditions”—intense, novel, and highly stimulating—he is more likely to rely on his amygdala, to be shortsighted, emotion-driven, and susceptible to coercion and peer pressure.
⁶⁵
In real life, his strong emotions and drives can “hijack” his ability for self-control and smart decisions.
⁶⁶

Harvard neuropsychologist Deborah Yurgelun-Todd explains, “adolescents are more prone to react with ‘gut instinct' when they process emotions but as they mature into early adulthood, they are able to temper their instinctive ‘gut reaction' response with rational, reasoned responses”... “Adult brains use the frontal lobe to rationalize or apply brakes to emotional responses. Adolescent brains are just beginning to develop that ability.”
⁶⁷

Hard science is telling us that his response to our bewildered question,
what were you thinking?
should not mystify us.
I don't know
, the teen we love may answer, shaking his head, perhaps with tears of shame and regret. Again, most of us didn't need Ph.D.'s to confirm what common sense told us all along—he
wasn't
thinking.

This is the case, Dr. Steinberg states, even when adolescents
know and understand
the risks involved.
⁶⁸
We can no longer assume that teens make poor choices—drug use, high-speed driving, unprotected
sex—because they are uninformed or unclear about the risks. As Dr. Steinberg reiterates, “There is substantial evidence that adolescents engage in dangerous activities
despite
knowing and understanding the risks involved.”
⁶⁹

There are additional factors that make adolescence a time of increased vulnerability. With the onset of puberty, the brain is flooded with sex hormones. For many teens, this activates strong drives, excitement, and emotional intensity. It's “a natural tinderbox,” as one neuroscientist termed the adolescent brain.
⁷¹
These hormones appear to alter the levels of dopamine, a neurotransmitter involved in the reward system. The alteration produces what's called a “reward deficiency”:
⁷²
in order to experience the same feeling of pleasure from a given activity, whether it's roller-coasters or rock concerts, teens require higher levels of novelty and stimulation. “It is as if they need to drive 70 miles per hour to achieve the same degree of excitement that driving 50 miles per hour had provided previously,” said Dr. Steinberg.
⁷³
Subsequently, there is an increased passion for novelty, thrills, and intensity. Add to that the sense of immortality and invulnerability that the average fifteen-year-old has, and you begin to grasp why parents of teens are nervous wrecks.

Dr. Dahl uses a powerful metaphor: an adolescent is like a fully mature car that's turbo-charged, but its driver is unskilled, and his navigational abilities are not yet fully in place.

Professionals in other fields have responded to these findings. The American Bar Association issued an official statement in 2003 urging all state legislatures to ban the death penalty for juveniles. “For social and biological reasons,” it read, “teens have increased difficulty making mature decisions and understanding the consequences of their actions.”
⁷⁴
The same year, the Missouri Supreme Court overturned a juvenile death sentence, with the court referring to the volume of studies documenting the “lesser ability of teenagers to reason.” The American Psychological Association (APA) followed, with a call for psychologists to “continue to bring forth existing and
new data on the limits of adolescent reasoning, judgment and decision-making.”
⁷⁵

But somehow the APA—or SIECUS, Planned Parenthood, and Advocates for Youth—has yet to acknowledge that this data is relevant to sex education. They're still insisting that deciding about sexual activity is “developmentally appropriate” for teens, that adults just need to “lay it all out there”—the risks and benefits: “Pour it all into teens' minds and watch them process it. They can do it,” Planned Parenthood advised .
⁷⁶

Yet, the premise for teaching “safe sex” is based entirely on the assumption that teens can think through complex issues, plan ahead, and consider consequences. “Reasoning, judgment and decision-making,” the very things they're still developing, are precisely the skills teens must have to determine their “readiness” for a “mature sexual relationship.” How, in light of the insights this young century has brought us about teen risk-taking and decision-making, can sex educators still tell kids, “only
you
know when you're ready,” and instruct parents to “respect” their teen's decision?

Memo to Debra Haffner, Ms. Klein, and the SIECUS and Planned Parenthood crowd: you know those “skills” you're so keen on adults providing teens, so they can make “informed decisions”? Studying their brains has indicated: it won't work .

You can drill it into them 24/7:
you must think, talk, and plan.
You can talk until you're blue in the face:
HPV, herpes, Chlamydia, and HIV; condoms, diaphragms and birth control pills; Plan B, abortion, or adoption
. And you can role-play all day: communication, negotiation, and assertiveness training.

Sorry, you may have all the good intentions in the world, but even if you provide
all the information
, and teach
all the skills
, you can't bank on producing a sexually responsible teen. The wiring isn't finished. The circuits aren't complete. The driver is unskilled, and only one thing will help: time.

Girls have another underdeveloped structure that increases their vulnerability, in addition to their prefrontal cortex. The cervix, the entrance to the uterus at the end of the vagina, plays a central role in female sexual health, but few people are aware of how it increases a girl's vulnerability to sexually transmitted infections.

The cervix is the site of two of the most common sexually transmitted infections, HPV and Chlamydia. HPV is necessary for cervical cancer to develop, and Chlamydia can cause chronic pelvic inflammatory disease, ectopic pregnancies, miscarriages, and infertility.

Girls under the age of twenty are being hit hardest
⁷⁷
by these epidemics.
⁷⁸
One reason is their immature cervix.
⁷⁹

It's critical to understand this. All things being equal,
⁸⁰
the cervix of an adult is more difficult to infect than the cervix of a teen. The more mature cervix is protected by twenty to thirty layers of cells. In contrast, the cervix of a teen
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has a central area called the transformation zone. Here the cells are only one layer thick. The transformation zone is largest at puberty, and it slowly shrinks as the cervix matures.
⁸²
The thin folds of fragile, single cells are transformed progressively into a thick, flat shield with many layers. The “T-zone” can be seen during a routine pelvic exam. It makes the cervix look like a bull's eye, which is fitting, because it's exactly where the bugs want to be.

Ask any self-respecting virus or bacteria about his life goal, and he'll tell you: to find a good home where I can be fruitful and multiply. That's the purpose of his existence. To reach that home, the layers of cells must be penetrated. It's difficult, if not impossible, to get through the many layers of the mature cervix.