Why Do Teenagers Take Risks? Part 2

Why do teenagers take such risks?

Many times teenagers take risks to ‘make a point.’ They are emotionally angry or hurt, and their emotional reaction is often a retaliatory over-reaction. The resulting behaviors may endanger others or themselves (or sometimes a mixture of both) though violence or defiance, cutting themselves, sexual or drug use acting out, or even driving irresponsibly, but the behavior carries a message! Good intervention must decipher the message from the behavior. Then the irritant can be removed, or if it cannot be removed, then the goal is give them better and more workable coping skills. This is often hard to do, and usually takes a lot of time and energy.

Teenagers may feel less ‘risk aversion’ because of their youthfulness. They often believe there is plenty of time in their lives to regain something if it is lost. They also tend not to see death as permanent, or they see the goal of their death as saying something like “my death will force you to understand or appreciate me.” Therefore, the prospect of risking death is not as aversive or frightening. This is perhaps because teenagers are more inclined to over-estimate the reward of a risk and not be so afraid of any subsequent discomfort or punishment. For example, the hope of gaining some euphoria, social status , or an object from drug use (usually they seek all three goals) is not outweighed by the possible malaise of a hangover or the risk of pregnancy. 

These behaviors can also be the result of depressions and other psychiatric conditions. This makes the diagnosis so complex. Is it an emotional developmental phase, situational, or psychiatric problem? And how much of the choice to choose a behavior stems from neurological immaturity? Problems get worse with mixtures of psychological and neurological issues.

This then brings us to the second neurologically based reason teenagers take risks. The process seeking the rewards is thought to stem from the over activation of reward centers (such as the nucleus accumbens) while there is also an under activation of regulating brain area ( the frontal lobes). The combination of a strong social or psychological need to express an emotion fails to undergo the necessary regulation of a fully mature frontal cortex.

We could gather all these thoughts under the term of the day by day, ever-changing psycho-neurobiology of decision-making.

A 23-year old looked back at his “wild youth” and told me that “now, in my ripe old years, I can finally stop and say ‘humm, do I really want to do that?’ ”

Let’s now mix in caffeine, alcohol or drugs. We don’t give drugs or alcohol to infants or young children because of what it does to their brain’s development. Can we – or should we — carry that same concern to the teenager and young adult? Will that be too much of a social change? Is it as important to protect the 20-year-old brain as much as the 13-year-old brain?

(Remember to visit our page of Basic Definitions of terms used in these postings. )

Thanks.

Next post: more about for teenage risk taking and information about the immediate versus delayed responses.

Why Do Teenagers Take Risks? Part 1

Why do teenagers take more risks?

Adolescents tend to have less aversion to risk than adults. There are several reasons for this. This entry will focus on one of them, and the other reasons will follow.

But first a bit of background.

The brain is only about 80% developed in adolescence. It is not complete until the late 20’s.

The brain also develops from the back to the front, and the last section to mature is the frontal lobe, where reasoning, planning, and judgment take place. Girls begin this process between 12 and 14 years of age, and boys start about 2 years later. (Which every parent and teacher knows!)

Learning takes place as the brain cells develop more robust synapses – that is, connections – that follow robust and repeated stimulations. This is called ‘long term potentiation,’ and it is this massive growth and pruning that allow teenagers to learn more easily than adults. But this growing process is also under the brutal attack of the sex hormones. So there the frontal lobes sit, faced with the challenge of making decisions beyond their level of maturity and experience. The early teenage frontal lobes also lack the needed connections going back to other parts of the brain – which may be more mature – that help make a proper decision. That is the turmoil of adolescence. So a ‘risk’ toa teenager is not processed or viewed in the same manner as an equal risk may be evaluated by an older adult.

The other factor is that kids are going into puberty at even younger ages, and so they may being doing so with even less mature brains. We’ll explore this too.

The first of the reasons for taking greater risk is that there is less ‘risk aversion,’ and this has been linked to an under activation of two parts of the brain: (1) the anterior insula, which is involved in emotions such as fear and disgust, and (2) to parts of the still under mature prefrontal cortex that monitors for conflict and error detection. So the effect is that the younger teenager’s logic doesn’t ‘see the danger’ the same way an older person may see it. This is why it is so important for the teenager to have external values and models that literally ‘dictate’ a model behavior. Some teenage risk taking is inevitable, and often can be beneficial, but some risks are riskier than others. They may not fully understand or agree with the adult reasoning regarding the extent of a particular risk, but because of their environment, they know when it is safer and prudent for them to follow the adults’ choice making procedure. This process of respecting the adult’s feelings about such things proceeds adolescence and should speak to the entirety of the child’s life.

The growth producing effect of this process has two parts. It teaches the importance of resisting an impulse, and of learning to live with delayed gratification and frustration. This is laid down in the neurons as a memory with a good outcome, and it leaves the teenager a step more mature both in a psychological and biological way. What follows is a reward for not doing something, and in that comes a piece of psychological strength. It may also get applause from the adult.

It’s not hard, sadly, to see the opposite happening if trustworthy adults are not around to give good advice and offer good models. The brain will biologically mature in and of itself, but the tools it learns as it matures is the product of what tools are made available to it during all of the childhood and across all the different stages of the maturing process.

How Brain Trauma Can Effect Brain Development

One aspect of brain development rests tightly with the brain’s personal history of physical trauma. This has, understandably and rightly so, been the recent focus of brain trauma in military personnel after a blast injury. The question has been if a blast, occurring from a distance and with no visible damage, could injure the brain. Historically the presence of emotional or cognitive changes following a blast, because of the lack of a ‘photographical injury’, left many suggestions that the residual psychological changes seen after a battle was only a psychosomatic outcome. This same injury process could apply to civilians under a bombing or shelling attack, or even after non-war related rough sports, physical abuse, or accidents.

A blast has two elements that clearly overlap. The ‘wind from the blast’ might throw people around and against walls, etc., which can toss the brain about within the skull. The actual ‘blast’ can be an explosion or a physical push, such as a hard football tackle, a fall, assault, or an auto injury. This is known as cranial shock-wave injury, and it can cause a concussion or other damages.  The second element involves the physics of a shock wave – an energy pulse and the resulting tissue disruption – as the pulse passes through the body. Tissues are also disrupted as the energy is displaced within the body. The brain is squeezed, the openings into and out of the brain might temporarily shift, and so on. Some blasts can also result in brain swelling, bleeding, vascular spasms, etc.

Medicine often refers to an injury as an insult. Our interest in this topic is because teenagers often suffer these types of insults. Young adults also are commonly first in battle. And since neurologically their brains have not been fully developed, they risk interfering with their brain’s ability to do so. For years it was nearly impossible to find structural changes in the brain after these insults. This was in part because of a lack of sophisticated enough neuroimaging tools.  Traditional CT and MRI scans identified no problems. But now diffusion tensor imaging (DT) can detect problems of axonal disruption. This is the topic of much discussion.

Each of us knows of people who were in battle, had football related head injuries, etc., who seem to be fine. With time, therefore, the statistical perspectives of these observations will be better established. So now there remain more questions than answers. But we must be aware of these new questions about how such insults might effect brain neurological and cognitive development and accept that these questions do not yet come packaged with answers.

A Quick, But Exciting News Brief — An Artificial Microbrain

University of Pittsburg bioengineering professor Henry Zeningue recently published a report in Lab on A Chip of the successful preparation of an engineered, very small, but active biological ‘brain’. They took proteins from the hippocampus cells from embryonic rats and allowed them to grow and connect with each other to form a natural network. The network was stimulated with external electrical pulse that resulted in 12 seconds of activity. The research group observed how the neurons transmitted and held onto the electrical charge for a time period much longer than expected; this is a form of memory. One theory of memory is that neurons in the cortex have extended electrical activities after an initial stimulus.

Observing what occurred in this small but effective model is a real step towards understanding how neuronal networks function and maybe even how they develop. This is the type of very basic science that helps us understand brain development.

Some Basic Definintions and Terms — A Starting Place

It is so exciting to have information that explains behaviors. The science can appear very complicated because there are so many parts to it. Most of us have little,  if any, introduction to the details of these parts. So as we go through the process of learning about the adolescent brain, it’s important to have some definitions. They’ll be posted here as a reference page, and on a separate webpage that will allow for frequent updating as needed. Don’t feel intimated by the volume of information. It takes time to master this roadmap. The brain is the most complicated computer known. But unlike the computer, the brain has a genetic pre-disposition, and it grows, changes, and reacts to physical and  psychological exposures.  This makes it ‘plastic’, which means it responds to good and bad influences.

This is a quick, and hopefully easy, introduction to some of the basic science.    (This will be a growing page ← click here to check for updates!)

The brain is the center of the nervous system, with an estimated 120 billion neuronal (neurons) cells, and 120 billion non-neuronal (glia) cells. It’s also estimated that there are 1000  trillion connections between the neurons; they connect via synapses. The brain is suspended in the cerebral spinal fluid, which softens how rapid movements might damage it. It’s also protected by a very zealous blood brain barrier that limits what can get into the central nervous system. But that blood brain barrier is not perfect, and they cannot keep out many  drugs, alcohol, or other toxins.

The neurons are divided into two groups – the grey matter (with no myelin), and the white matter (with the white myelin coatings).  A neuron is a long cell that acts like a biochemical wire – when stimulated it transmits information. Each neuron can pick up signals from one or more other neurons, and each neuron can also send information out to one or more other  neurons. A neuron is like an  arm, and the reception and transmissions occur in areas of dendrites. Spread your fingers open and wide – they are like the dendrites.  We have recently  learned that there is a second burst of grey matter growth just before puberty.

Pruning  is a natural process of removing neurons to further improve the networking capacity of a particular area of the brain, to make circuits less ambiguous, which is turn improves  synaptic efficiency. There are appear to be two periods of grey  matter synaptic growth followed by pruning, in early childhood and – which is new information — in adolescence. A 3 year old will have many more synapses that an adult. Synaptic circuits most frequently activated will be preserved; ineffective, weak or unused synapses will be pruned, similar to a gardener shapes a tree. For humans, the gardener is a mixture of nature and nurture.  We are rapidly learning the details of this second pruning in adolescence.

Glia, or glue cells, are the non-neuronal parts.  They regulate the environmental outside the neurons. The role of glia cells has recently been much better understood, with consideration that they may have as important a role in many conditions, such as depression, as the neurons. The three types of glial cells produce a healthy, protective and clean environment so the neurons can operate as best possible.

Myelin is the  product of a glial cell. It is an electrical insulation material that forms a sheath, around the axon.  Myelin production of myelin starts in the 14^th week of fetal development, but is occurs most rapidly from birth to adolescence.  Having myelin makes it possible for neurons to more rapidly transmit the information.  Myelination reduces the loss of the electrical current from the axon.

Two broad classes of neurons exist – interneurons, which form local circuits, and projection neurons, which take information to other regions of the brain or body. Most neurons are
interneurons.  All of these make up the developing circuits and connections that we are interested in as the brain matures.

Cytoarchitecture is the term used to explain how Korbinian Brodmann organized the cortical neurons and glial cells into 47 areas. The organization of these areas will become important
later on as we explore the developing adolescent brain. The highest area of computation is within the grey area of the cerebral cortex.

Neuroplasticity is the ability of the brain to change with learning and experiences.

Next: We start to look at the recent findings on how the adolescent brain develops.

Understanding and Protecting A Teenager’s Ability For Good Brain Development

Welcome to the first post of my blog.

I am psychiatrist, and one of themes I have been following is the importance of protecting the adolescent brain so it has the best opportunity to develop both neurologically and psychologically. The past few years have provided us with incredible insights. We need to share these findings and ideas so we better know how to approach to the adolescent experience.

I will periodically post new findings, explain old findings, and raise issues that help explain the interplay of  brain development and psychological maturation.

Let’s begin with a recent interview with Dr David Gross, a psychiatrist, who gives a solid basic outline of the topic. He also includes material on what happens when the developing brain is exposed to substance abuse, in particular marijuana. (Click to listen → ) The Adolescent Brain — This interview is part of the Experts Speak podcast series from the Florida Psychiatric Society.

(Note: All opinions, etc., expressed in this blog are exclusively mine, and not necessarily of groups or organizations to whom I offer links.)

Thanks.

Abbey Strauss MD

© Abbey Strauss 2011