Adolescence is often a disorderly metamorphosis between childhood and adulthood, a time of dreams, opportunity and hope, but also one of danger and vulnerability. Dramatic alterations in brain circuitry accompany the physical changes in adolescence. There is an almost adult body but an immature nervous system. Teens must navigate astonishing complexities in today’s society and without a fully developed cortical system that can be readily used to inhibit impulsivity and assess risk with mature judgment. Children are entering puberty far earlier than they have historically. The average age children reach puberty today is between twelve and thirteen. In 1860 the average age was fifteen and a half. The end result of this change is that the adolescent period is stretching.
Someone once said that adolescence is similar to putting an unskilled driver in a car. During this period of life there is a flurry of development in the neurobehavioral systems involved in emotional regulation and behavioral choices. This growth spurt lasts well into adulthood, resolving around eighteen or nineteen years old. It involves the areas of our brains that are related to cognitive control of impulses and decision making. At the same time there is an activation of reproductive circuitry with a concomitant increase in emotional intensity and sexual focus. Hormonal challenge during this period interfaces with other brain chemistry resulting in characteristic strong mood changes.
Self regulation- the ability to think through decisions and inhibit impulsivity- is perhaps the most important of all adulthood skills. A competent adult is able to inhibit and modify behavior so that negative future consequences are avoided. This ability is at an all time low during adolescence. In addition if you add the possible disinhibiting effects of alcohol, peer “pack behavior” sleep deprivation, or drugs, the result is sometimes disaster. Indeed the probability of mortality increases three hundred percent during the teen years. These rates fall once full adult maturity is reached. According to government reports (CDC, 1997) eight percent of high school students attempt suicide yearly. The ability to think before acting so as to thoughtfully choose between difficult paths of action and to interrupt risk behavior is what the concept of self regulation is all about. Unfortunately, the brain neural networks governing self regulation do not fully mature until late adolescence. It is from the brain imaging research that we understand that increases in risk taking in adolescence are biologically driven.
Adolescents experience increased sensitivity to rewards that is also related to changes in neurochemistry and brain networks. Eighty percent of high school seniors have tried alcohol and sixty-six percent say they have had an episode of consuming more than five drinks at a single session-a dangerously large amount of alcohol. Smoking is most likely to begin in adolescence: seventeen percent of high school seniors in the U.S. say that they smoke daily.
Regular drug and alcohol consumption affects learning in complex ways. The brain grows accustomed to receiving external euphoric drugs and decreases the output of some of its own “reward chemicals.” In addition, the brain learns to anticipate the intense euphoric chemistry so that the youngster becomes sensitive to cues that may be related to a drug or alcohol experience. These over learned associations become easily triggered and may lead to craving the euphoria-inducing substance again. All of these effects usually occur outside the conscious awareness of the young adventurer. In addition, a recent study found that teens who had regularly abused alcohol experienced a ten percent decrease in ability to retain verbal and nonverbal information when compared to their non-drinking peers. Ten percent translated into a full letter grade decrease in classroom performance. Brain imaging studies reveal that adolescents who began drinking early- around age eleven- had more discernable deficits on MRI scans, particularly relating to hippocampal function, an area of the brain that is primarily involved in memory.
Alcohol, as well as many drugs, interfere with sleep and thus disrupt learning consolidation and memory. Sleep researchers have recently begun to study the natural sleep patterns during the teen years. Clearly we know now that adolescents are biologically wired to want to go to sleep later. They need just over nine hours of sleep nightly. Of course, the early school schedule wrecks havoc with these normal developmental trends. This is a time of rapid physical growth that correlates with increased need for sleep. Learning and memory consolidation primarily occurs during REM, stage three, sleep. Adolescence and late adolescence usually marks the period of most intensive learning in life. Sleep profoundly impacts memory, learning, attention, concentration, immune function and mood regulation.
An adolescent system in transition can be profoundly impacted by sleep deprivation. In fact, because of the circadian rhythm changes during puberty many teens struggle to meet the early school schedule and a large percentage are sleep deprived. Sleep loss prevents restoration of complex brain interconnections, especially those connected to the prefrontal cortex, higher thought centers. Complex thought is the basis of self regulation. In addition, there is a profound correlation between sleep loss and depression and mood regulation. Since suicide is at an all time high in adolescence, adequate sleep is extremely important.
There is little doubt that today’s teens are less protected than in earlier times, especially in this country. They are exposed to graphic images of violence and sex that were far less accessible and widespread in the past. Media commerce, in the form of movies, television and the internet, use the highly arousing stimuli of sex and violence to attract attention and arouse people to action in order to sell their wares. Children and adults are sadly exploited and, for the most part, have no awareness of their exploitation. Kids become accustomed to over stimulation, under protection, and over exposure. One only has to visit a movie theater to experience assaultive images of aggression and sex in previews and even walking past video machines while entering,, the movie house. It is quite common for adolescents to fraternize with binge drinking, pot, crystal methamphetamine, and other drugs that provide euphoria and disinhibition. Since highly stimulating experiences are deeply etched in memory, they are rather easily elicited. Some high school girls and boys may find themselves disinhibited by alcohol or drugs, falling mindlessly into sexual behavior portrayed so freely in the media. Sexual bonding may occur under these circumstances with little or no discernment.
Related to these phenomena is the recent finding that adolescent brains in transition seem to neurochemically fluctuate, especially in serotonin and dopamine, two systems whose dysregulation often lead to one choosing smaller, immediate rewards over larger delayed ones. All of this can predispose teens to poor choices and sometimes drug and alcohol abuse, unplanned pregnancy, or even death. Adolescents are more likely to take risks in groups than when alone. They tend to seek high levels of novelty and stimulation compared to other periods in life
For parents this period of their child’s life development is frequently a challenge. It is hard to develop and maintain guidance strategies that facilitate the adulthood skills of learned responsibility and successful and intentional self regulation without being overly constricting. Until now we have not clearly understood that our higher thought centers are going through such dramatic shifts during puberty. Because teens look mature and likely because many become intensely strong willed and sometimes volatile, parents often do not monitor them as carefully as may be necessary for safety and future well being. It could be cogently said that today’s world is a dangerous place for teens. Thirty two percent of adolescent deaths occur in car accidents. Boys die two to three times as often as girls. Risk taking for teen males is at an all time high during this developmental era. The key for parents is to protect their teen children without subjecting them to too much control.
Changes in the adolescent brain may occur quite out of our awareness because we cannot see the development going on there (other than in neuroimaging) that we so readily see in the physical changes of puberty. Sharing the knowledge that we now have about what is actually going on in our brains during adolescence may well facilitate a more collaborative effort to find that careful path of adult guidance and protection without oppressive control.
Educating parents, teachers and teens to the present knowledge of dynamic and dramatic adolescent brain changes and their behavioral and psychological manifestations will hopefully demystify characteristic emotional intensity and impulsivity during this life period. As teens become more educated as to what is happening to their minds and bodies, they may gain a bit of distance from the intensity of feeling states during this time. It is even possible that this enlightened understanding could lead to more adolescent, parent, and teacher collaboration in mutually caring awareness to guide and manage teens so as to avoid disaster and find a path to a good and happy life.
- Dr. Linda Klaitz, Medical Psychologist