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The public seems to have a boundless appetite for titillating stories of misbehaving teens, and news organizations are more than happy to oblige. Readers and viewers are left scratching their heads, wondering what sort of derelict parenting could have led to such behavior, and meanwhile assuring themselves that their their kids would never behave in such a way. As it turns out, emerging neuroscience research reveals there’s more to the story than what we hear from drive-by journalists only interested in stoking public outrage for page clicks. Journalists, parents, and shocked observers tend to overlook a unique feature of brain development that offers crucial context for understanding why these events keep happening. When public discourse washes over important nuances it does a disservice to the young adults who need more enlightened direction from their parents, educators, and mentors.
Teens are naturally prone to risk taking behavior
A defining feature of the teen brain is the ability to adapt to new environments by modifying networks that help different regions of the brain communicate. While this trait allows major progress in terms of critical thinking and socializing, the teen brain is also prone to dangerous behaviors.
Few examples illustrate the phenomenon more clearly than the data behind accidental drownings, which are more common among teens than grown adults. As Temple psychology professor Laurence Steinberg, notes in a recent NPR broadcast, the disproportionate drowning rate is not due to lack of skill or energy. “Adolescents are quite strong. So there's no good reason why 16-year-olds should drown more often than 35-year-olds, but they do,” he said. “We think that it probably has to do with bad judgment and bad decision-making, and it's that kind of thing that really threatens the well-being of teenagers, here and in other countries, as well.”
Recent studies have shown that the riskiest behaviors can be traced, at least in part, to a mismatch between development of networks in the limbic system and prefrontal cortex. The limbic system drives emotions, and during puberty development of this region accelerates disproportionately compared to other regions. Meanwhile, networks in the prefrontal cortex, which controls judgment and impulses, develop later. This mismatch is a crucial factor driving the tendency towards risky behavior among teens.
During adolescence brain development is driven by complex processes, providing opportunity for the brain to polish and refine itself for surviving in new environments. As different parts of the brain develop better connectivity, this development facilitates communication among the different regions, allowing more sophisticated integration between the various parts. The changing relationship between brain systems that govern emotion sparks an increase in risk taking and desire for social interaction.
While these adaptive behaviors, common among most mammals, encourage adolescents to eschew the familiar in favor of novelty, they also present dangers that come along with exploring new territory. Combined with the complexities of navigating contemporary life, the pitfalls of this natural tendency towards risk-taking is compounded by unsupervised alcohol use and later amplified by social media.
“As a result,” notes a recent New York Times story, “adolescence is both a time of opportunity and vulnerability, a time when much is learned, especially about the social world, but when exposure to stressful events can be particularly devastating.”
Dr. Frances Jensen, professor of neurology at University of Pennsylvania, summarizes the paradox of the adolescent brain succinctly in her book “The Teenage Brain”:
“[The teenage brain] has an overabundance of gray matter (the neurons that form the basic building blocks of the brain) and an undersupply of white matter (the connective wiring that helps information flow efficiently form one part of the brain to the other) – which is why the teenage brain is almost like a brand-new Ferrari: it’s primed and pumped, but it hasn’t been road tested yet.”
It has long been established that the limbic system, which governs emotion, matures much earlier than the frontal lobe networks, which help to regulate rational decision making. “Appreciating the interplay between limbic and cognitive systems is imperative for understanding decision making during adolescence,” counsels Jay Giedd, profess of psychiatry at University of California, San Diego. Frontal lobe circuitry navigates executive functioning (e.g. regulation of emotion, long-term planning, and response inhibition). The areas of the brain responsible for integrating these parts mature later than others, not reaching full maturation until the mid to late 20s. The changing relationship between the frontal and limbic systems helps to explain the cognitive and behavioral changes that occur in the teenage years. Properly understanding this unique stage of development provides context that can steer intervention practices in a more thoughtful direction.
It’s not all bad news
From the perspective of evolutionary adaptation, Geidd writes, “it is not surprising that the brain is particularly changeable during adolescence—a time when we need to learn how to survive independently in whatever environment we find ourselves.” Humans are equipped to survive in a wide range of extreme conditions, and these capabilities change over time. Centuries ago our brains may have been optimized for hunting and gathering. Now, our brains may be optimized for reading or critical thinking. “This incredible changeability, or plasticity, of the human brain is perhaps the most distinctive feature of our species. It makes adolescence a time of great risk and great opportunity.”
Laurence Steinberg, a psychology professor at Temple, studies brain development in teens and recognizes this tradeoff between curiosity and risk. Steinberg was recently interviewed for a New York Times story where he offered this observation: “If brain plasticity is maintained by staying engaged in new, demanding and cognitively stimulating activity, and if entering into the repetitive and less exciting roles of worker and spouse helps close the window of plasticity, delaying adulthood is not only O.K.; it can be a boon.” Exposure to new situations when the brain is plastic helps us develop new skills and sharpen existing ones. This feature of the adolescent brain primes us to benefit from developmental experience in the future.
Conversely, Steinberg is well aware of the drawbacks, as he recently told The Atlantic: “It’s a huge public-health problem, since the things that teenagers are hurt by (or die from) generally aren’t diseases or illnesses, but reckless behaviors, like risky driving.”
Steinberg has researched specifically why teens are more likely to take greater risks when around their peers, and his findings offer critical lessons for understanding and promoting student safety on campus. “In essence, we had discovered that the effect of peers on adolescent risk taking may be hard-wired in the adolescent brain because of the impact of peers on the brain’s reward centers,” he writes. “Just being around your friends is so rewarding that it makes you do crazy things.”
In a recent cover story analyzing the latest research on the adolescent brain, Scientific American offers wise counsel on exercising humility in diagnosing the root cause of teen behavior. “People will see better that behaviors such as risk taking, sensation seeking, and turning away from parents and toward peers are not signs of cognitive or emotional problems,” the authors counsel. “They are a natural result of brain development, a normal part of adolescents learning how to negotiate a complex world.”
Thanks to more public awareness, the old narrative (the teen brain matures when it gets bigger in size) is giving way to the new narrative: the teen brain matures when its different parts communicate better.
Risk taking is even more common for males
The greater challenge for parents of teen boys – and organizations composed of male college students – is the reality that men are more likely than women to exhibit this risk taking behavior resulting from mismatched development between different regions of the brain. This gender difference manifests itself in a host of ways – from performance in school to crime stats. According to a recent report by The Economist, “teen boys in affluent countries are two times more likely than girls to fail math, reading, and science courses.”
The author proceeds to describe the phenomenon in stark if not cynical terms: “The world’s most dysfunctional people are nearly all male. Men have always been more violent than women, even if they are less violent now than they used to be. In America today they commit 90% of murders and make up 93% of the prison population. They are also four times more likely to kill themselves than women are.”
Brain development continues well into the twenties
“We once thought that the brain didn't change that much after earlier childhood,” explains Dr. Johanna Jarchoa in a recent interview for Vice. “But what we've seen is that the brain continues to undergo really profound changes up until your early 20s. It's still quite malleable, so being exposed to different influences in your social environment can really have a profound impact on the way that your brain continues to develop.”
Coverage by Scientific American has noted the same phenomenon: “The prefrontal cortex functions are not absent in teenagers,” the authors explain “They are just not as good as they are going to get. Because they do not fully mature until a person’s 20s, teens may have trouble controlling impulses or judging risks and rewards.”
Myelin is a substance found in the brain that facilitates the movement of signals between different parts of the brain. Commonly referred to as “white matter” for its white color, myelin is essential for the information transmission that contributes to brain development. Building off earlier research by the National Institute of Mental Health, researchers at UCLA discovered that myelin continues to be produced well into a person’s 20s, “making the communication between brain areas ever more efficient,” according to Dr. Frances Jensen, author of “The Teen Brain.”
“There is no bright line, no numerical age our boundary or demarcation at which we can say someone is neurologically mature,” Dr. Jensen advises in her book. “Instead, it is becoming increasingly clear that brain maturation extends well into a person’s twenties.”
Laurence Steinberg, mentioned earlier, confirmed this relatively new discovery during an interview for the Aspen Ideas Institute, citing new research: “We can't point to a specific chronological age at which the adolescent brain becomes an adult brain, because different brain regions mature along different timetables, but important developments are still ongoing during the early 20s.”
“What determines teen behavior is not as much late development of executive functioning or early onset of emotional behavior but mismatch in the timing of the two developments,” Steinberg continued. “This leaves a decade of time during which imbalances between emotional and contemplative thinking can reign.”
Improving public awareness leads to more effective remedies
Delayed development of the prefrontal cortex, crucial for sound judgment and impulse control, has been the subject of public policy debates ranging in scope from parenting best practices all the way to legislative agendas, with the most recent debates surrounding the role age should play in the juvenile court systems. Understanding this phenomenon is crucial context for properly understanding why this behavior happens and how it can be stopped or channeled into more productive uses.
During the transition from youth to full adult, adolescents are subjected to risks while learning the skills required for succeeding as an independent adult. “Adolescents across a variety of species exhibit age-specific behavioral characteristics that may have evolved to help them attain the necessary skills for independence,” writes Linda Patia Spear in a paper for the journal Current Directions in Psychological Science.
The tumultuous nature of this developmental period is not unique to humans; many different species studied by developmental psychologists have demonstrated the evolutionary phenomenon of adapting in similar ways during this window of development. Like their human counterparts, writes Spear, rats undergoing the developmental transition of adolescence show an increase in risk-taking behavior, illustrated by a tendency to seek novel stimuli and explore unknown areas more avidly than at other stages of development.
As Scientific American notes, the idea of “prolonged plasticity” discussed earlier presents tradeoffs in the form of greater vulnerabilities associated with mental illness and substance abuse. However, recognizing this phenomenon gives optimism that interventions can change a teenager’s life course. As we’ve seen, discussions between teens and parents can influence development.
Learning more about unique qualities of the adolescent brain will help us all learn how to separate unusual behavior that is age-appropriate from that which might indicate illness. Scientific American offers optimism on the fruits of deeper understanding: “Such awareness could help society reduce the rates of teen addiction, STDs, motor vehicle accidents, unplanned pregnancy, homicide, depression and suicide.” Indeed, clinical psychologists are already using this research to help parents communicate with their kids to proactively to prevent risky behavior. Judges, attorneys, and social workers in the juvenile criminal justice system are working with state legislatures to focus on rehabilitation in place of incarceration.
The applications of this research touch many of the biggest problems the world is trying to solve today. Across all cultures adolescents are the most vulnerable to be recruited as terrorists and soldiers. Conversely, young adults are most likely to be influenced to become teachers and engineers. Greater understanding of the teen brain could help to steer younger adults towards a more productive life paths. Improved public awareness could also help judges and jurors reach more empathetic decisions in criminal trials. The applications to improving campus safety at U.S. colleges is another area that could benefit from better understanding of adolescent brain development. Campus judicial systems and student organizations might take a more developmental approach to helping students learn from mistakes. And critics of fraternity and sorority life might begin to recognize the importance of forming positive social bonds at a critical window for young adults.