Psychology | Wiley | The Adolescent Brain, D___Name:

TED Talk: “The mysterious workings of the adolescent brain,” 2012, by Sarah-Jayne Blakemore (neuroscientist)

  1. Fill in the blanks below:
    About 15 years ago, it was widely assumed that the vast majority of brain development takes place in the first _____ years of life.

But we now know that idea is false, thanks to advances in brain imaging technology, such as ______(magnetic resonance imaging), which allow neuroscientists to track brain structure and function across the lifespan.

  1. Which part of the brain changes most dramatically during adolescence? Describe this part of the brain:
  2. During adolescence, an important developmental pruning process takes place in several parts of the brain, including the prefrontal cortex. Fill in the blanks below:

Synapses that are being used are ______, and synapses that aren’t being used in that particular environment are ______away. You prune away the weaker branches so that the remaining, important branches, can grow stronger. This process effectively fine-tunes brain tissue according to the species-specific ______.

  1. In Dr. Blakemore’s lab, they study the social brain, the network of brain regions that we use to understand other people and to interact with other people. In behavioral studies conducted in her lab and around the world, they’ve found that adolescents struggle to do something very important in the daily lives of human beings. Explain below. Note: It will take several minutes for her to explain these behavioral studies and come to her conclusion.
  1. Fill in the blanks below:
    Adolescents take more ______than children or adults, and they’re particularly prone to engage in this kind of behavior when they’re with their friends.

This behavior can be understood by studying the ______system, which is deep inside the brain, involved in things like emotion and reward processing. This system is hypersensitive to the rewarding feeling of risk-taking in adolescents compared with adults. Meanwhile, prefrontal cortex, which stops us from taking excessive risks, is still very much in development in adolescents.

  1. Fill in the blank: The teen brain undergoes remarkable development and is highly adaptable and malleable. Teaching shapes these developing brains, and yet ______% of teens around the world do not have access to secondary education.
  2. (Post-viewing) Dr. Blakemore said that “heightened risk-taking, poor impulse control, self-consciousness—shouldn’t be stigmatized. It actually reflects changes in the brain that provide an excellent opportunity for education and social development.” What do you think she meant by that?

Adolescent Angst: 5 Facts about the Teen Brain, by Robin Nixon, livescience

They are dramatic, irrational and scream for seemingly no reason. And they have a deep need for both greater independence and tender loving care.There is a reason this description could be used for either teens or toddlers: After infancy, the brain's most dramatic growth spurt occurs in adolescence."The brain continues to change throughout life, but there are huge leaps in development during adolescence," said Sara Johnson, an assistant professor at the Johns Hopkins Bloomberg School of Public Healthwho reviewed the neuroscience in "The Teen Years Explained: A Guide to Healthy Adolescent Development" (Johns Hopkins University, 2009) by Clea McNeely and Jayne Blanchard.And though it may seem impossible to get inside the head of an adolescent, scientists have probed this teen tangle of neurons. Here are five things they've learned about the mysterious teen brain.

New thinking skills: Due to the increase in brain matter, the teen brain becomes more interconnected and gains processing power, Johnson said. Adolescents start to have the computational and decision-making skills of an adult – if given time and access to information, she said.But in the heat of the moment, their decision-making can be overly influenced by emotions, because their brains rely more on the limbic system (the emotional seat of the brain) than the more rational prefrontal cortex, explained said Sheryl Feinstein, author of "Inside the Teenage Brain: Parenting a Work in Progress" (Rowman and Littlefield, 2009)."This duality of adolescent competence can be very confusing for parents," Johnson said, meaning that sometimes teens do things, like punch a wall or drive too fast, when, if asked, they clearly know better.

Intense emotions: "Puberty is the beginning of major changes in the limbic system," Johnson said, referring to the part of the brain that not only helps regulate heart rate and blood sugar levels, but also is critical to the formation of memories and emotions.Part of the limbic system, the amygdala is thought to connect sensory information to emotional responses. Its development, along with hormonal changes, may give rise to newly intense experiences of rage, fear, aggression (including toward oneself), excitement and sexual attraction.Over the course of adolescence, the limbic system comes under greater control of the prefrontal cortex, the area just behind the forehead, which is associated with planning, impulse control and higher order thought. As additional areas of the brain start to help process emotion, older teens gain some equilibrium and have an easier time interpreting others. But until then, they often misread teachers and parents, Feinstein said."You can be as careful as possible and you still will have tears or anger at times because they will have misunderstood what you have said," she said.

Peer pleasure: As teens become better at thinking abstractly, their social anxiety increases, according to research in the Annals of the New York Academy of Sciences published in 2004.Abstract reasoning makes it possible to consider yourself from the eyesof another. Teens may use this new skill to ruminate about what others are thinking of them. In particular, peer approval has been shown to be highly rewarding to the teen brain, Johnson said, which may be why teens are more likely to take risks when other teens are around.

Measuring risk: "The brakes come online somewhat later than the accelerator of the brain," said Johnson, referring to the development of the prefrontal cortex and the limbic system respectively.At the same time, "teens need higher doses of risk to feel the same amount of rush adults do," Johnson said.Taken together, these changes may make teens vulnerable to engaging in risky behaviors, such as trying drugs, getting into fights or jumping into unsafe water. By late adolescence, say 17 years old and after, the part of the brain responsible for impulse control and long-term perspective taking is thought to help them reign in some of the behavior they were tempted by in middle adolescence, according to McNeely and Blanchard. What is a parent to do in the meantime? "Continue to parent your child." Johnson said. Like all children, "teens have specific developmental vulnerabilities and they need parents to limit their behavior," she said.

'I am the center of the universe’:The hormone changes at puberty have huge affects on the brain, one of which is to spur the production of more receptors for oxytocin, according to research detailed in a 2008 issue of the journal Developmental Review.While oxytocin is often described as the "bonding hormone," increased sensitivity to its effects in the limbic system has also been linked to feeling self-consciousness, making an adolescent truly feel like everyone is watching him or her. According to McNeely and Blanchard, these feelings peak around 15 years old.While this may make a teen seem self-centered (and in their defense, they do have a lot going on), the changes in the teen brain may also spur some of the more idealistic efforts tackled by young people throughout history."It is the first time they are seeing themselves in the world," Johnson said, meaning their greater autonomy has opened their eyes to what lies beyond their families and schools. They are asking themselves, she continued, for perhaps the first time: What kind of person do I want to be and what type of place do I want the world to be?Until their brains develop enough to handle shades of gray, their answers to these questions can be quite one-sided, Feinstein said, but the parents' job is to help them explore the questions, rather than give them answers.

  1. Summarize the key findings about the science of the adolescent brain. Example: Teen brains rely more on the limbic system (the emotional seat of the brain) than the more rational prefrontal cortex.
  1. How could some of the “flaws” of the teenage brain be managed/remedied by parents, educators, and the community at large?

Adolescent Brains are Works in Progress, by PBS FRONTLINE

Over the past 25 years, neuroscientists have discovered a great deal about the architecture and function of the brain. Their discoveries have led to huge strides in medicine, from pinpointing the timing at which children should be operated on for vision problems to shedding light on the mechanisms that cause such diseases as schizophrenia. Much of the early focus of the research was on the early years of development or on diseased brains. Now, with the advent of new imaging techniques, researchers are able to examine normal brains and brains of people throughout their lives.

Before the advent of magnetic resonance imaging (MRI), scientists already knew a lot about how the brain functioned. When people suffered brain damage or injury to particular parts of the brain, scientists could see what functions were impaired, and infer that the injured areas governed those functions. For example, people who had strokes in the area of the brain affecting speech lost the ability to speak. Autopsies showed when particular parts of the brain matured, the connections were wrapped in white matter, or myelin.

With functional MRIs, researchers can see how the brain actually functions -- what parts of the brain use energy when performing certain tasks. They know, for instance, the particular part of the brain that "lights up" when performing a visual task. Those images in which brain activity is measured are called "functional" because they measure how the brain performs tasks rather than simply mapping out the structure of the brain.

A Discussion on Changes in the Prefrontal Cortex: Studies from Dr. Jay Giedd at the National Institute of Mental Health:

Giedd and his colleagues found that in an area of the brain called the prefrontal cortex, the brain appeared to be growing rapidly just before puberty. The prefrontal cortex sits just behind the forehead. It is particularly interesting to scientists because it acts as the CEO of the brain, controlling planning, working memory, organization, and modulating mood. As the prefrontal cortex matures, teenagers can reason better, develop more control over impulses and make judgments better. In fact, this part of the brain has been dubbed "the area of sober second thought."

The fact that this area was still growing surprised the scientists. Although they knew that the brain of a baby grew by over-producing synapses, or connections, they had not known that there was a second period of over-production. In a baby, the brain over-produces brain cells (neurons) and connections between brain cells (synapses) and then starts pruning them back around the age of three. The process is much like the pruning of a tree. By cutting back weak branches, others flourish. The second wave of synapse formation described by Giedd showed a spurt of growth in the frontal cortex just before puberty (age 11 in girls, 12 in boys) and then a pruning back in adolescence.

Even though it may seem that having a lot of synapses is a particularly good thing, the brain actually consolidates learning by pruning away synapses and wrapping white matter (myelin) around other connections to stabilize and strengthen them. The period of pruning, in which the brain actually loses gray matter, is as important for brain development as is the period of growth. For instance, even though the brain of a teenager between 13 and 18 is maturing, they are losing 1 percent of their gray matter every year.

Giedd hypothesizes that the growth in gray matter followed by the pruning of connections is a particularly important stage of brain development in which what teens do or do not do can affect them for the rest of their lives. He calls this the "use it or lose it principle," and tells FRONTLINE, "If a teen is doing music or sports or academics, those are the cells and connections that will be hardwired. If they're lying on the couch or playing video games or MTV, those are the cells and connections that are going to survive."

Jay Giedd and his colleagues have given us a new window into understanding how the pre-adolescent brain develops. However, knowing more about the structure of the brain does not necessarily tell us more about the function of the brain. It is a good hypothesis that if a particular structure is still immature, the functions it governs will show immaturity. Thus, there is fairly widespread agreement that adolescents take more risks at least partly because they have an immature frontal cortex, because this is the area of the brain that takes a second look at something and reasons about a particular behavior. However, moving from structure to function, deciding what behavior is caused by what part of the brain is much more complicated.

Despite the caveats about how much we can know about brain function and how readily any of this work can be translated into policy, it is clear from the research that the brain is a good deal more plastic or changeable than we once thought. Important structural changes are taking place well into adolescence and beyond. Except for a few well-defined sensitive periods for certain types of vision, hearing, and first-language learning, the brain is capable of growth well beyond the first few years of life. An important part of the growth is happening just before puberty and well into adolescence. The brain research adds new dimensions to our understanding of adolescence -- a time of both heightened opportunity and risk.

  1. Why is the prefrontal cortex sometimes called (among neuroscientists) the “area of sober second thought.” What’s happening to this region of the brain during adolescence?
  2. Why does Dr. Giedd think that what teens do can affect them for the rest of their lives?

Brain Immaturity Could Explain Teen Crash Rate, by Elizabeth Williamson, Washington Post

By most physical measures, teenagers should be the world's best drivers. Their muscles are supple, their reflexes quick, their senses at a lifetime peak. Yet car crashes kill more of them than any other cause -- a problem, some researchers believe, that is rooted in the adolescent brain. A National Institutes of Health study suggests that the region of the brain that inhibits risky behavior is not fully formed until age 25, a finding with implications for a host of policies, including the nation's driving laws.

Last month, Sen. William C. Mims (R-Loudoun) cited brain development research in proposing a Virginia bill that would ban cell phone use in vehicles by drivers younger than 18. It passed Friday. In Maryland, Dels. Adrienne A. Mandel and William A. Bronrott said the research could bolster three bills the Montgomery County Democrats submitted to the legislature Friday. The bills would expand training and restrict passenger numbers and cell phone use for certain teenage drivers.

The measures also are supported by crash statistics and a soon-to-be-released study from Temple University, which used a driving-style test to show that young people consistently take greater risks when their friends are watching. "This goes toward supporting evidence that the judgment of teens further deteriorates with distractions. These crashes are preventable," Mandel said. "I would welcome [researchers'] testimony at our bill hearings."

The research has implications beyond driving: Attorneys cited brain development studies as the U.S. Supreme Court considered whether juvenile offenders should be eligible for the death penalty. [In Roper v. Simmons (2005), in a 5-4 vote, the U.S. Supreme Court prohibited juvenile capital punishment. Justice Kennedy, writing for the majority, wrote: “When a juvenile offender commits a heinous crime, the State . . . cannot extinguish his life and his potential to attain a mature understanding of his own humanity.”]

At Temple University in Philadelphia, psychology professor and researcher Laurence Steinberg and plans a new study: scanning teenagers' brains while they perform a task that simulates driving decisions, in an effort to understand the biological underpinnings of risk-taking among young people.

Volunteers in three age groups -- 13 to 16, 18 to 22 and 24 and older -- were told to bring two friends to the study, which involved an arcade-style driving game. To "win," participants guided a car through a course as quickly as possible. Periodically, a yellow warning light flashed, and some time later a "wall" popped up. If players hit it, they lost all their "points." Participants took the test alone and with their friends in the room. Researchers found that those in the two younger groups consistently took more chances with friends present. Those 24 and older behaved equally cautiously, regardless of whether friends were watching. The results help show why teenagers are more likely to drink, take drugs or commit crimes in groups, he said. They're also reflected in auto crash statistics.