Although we may consider some of the actions and decisions teenagers are making completely outrageous, we cannot hold them entirely accountable for the sometimes negative consequences they endure due to poor reasoning skills. David Dobbs explores the science behind the teenage brain in his article, The Beautiful Brain, featured in the October issue of National Geographic.
Contrary to popular belief, the human brain is not done developing or maturing after elementary school. The brain goes through a massive upgrade as humans go through adolescence. This development is the biggest throughout the human life span and is responsible for essential reasoning skills. During this period, the axons transmission speed increases by one hundred times. This is due to the insulation of myelin, as we discussed previously in Animal Physiology class (it is not my fault, my brain is not fully myelinated). Also, the dendrites are growing stronger and more capable of passing signals. Another change that is contributing to the brains power is the thinning of the cortex while the corpus callosum thickens and improves the flow of messages throughout the brain. Basically, all of the components of the brain which allow for cognition are strengthened. This process allows for the brain to act more efficiently and quicker. The focus is on the front part of the brain and contributes to an individual’s complex thinking instead of basic skills such as movement. Dobbs describes this proceeding development as essential for “balancing our impulses, desires, goals, self-interest, rules, ethics, and altruism.”
The teenage brain acts differently than the adult brain. An example discussed in the article was how teenagers take much more risks in life than adults do. After much experimental research, the determining factor that induced the risk taking was the teenage brain being more attuned to oxytocin. This hormone allows teenagers to weigh the rewards of a successful risk differently than an adult would. The hormone also makes social connections more rewarding as well, possibly explaining while teens are more vulnerable to peer pressure.
The most essential organ to human existence is the brain. We can credit the not so thought out choices of teenagers to the fact that the frontal part of their brains is not as matured as an adult brain. This late maturation is all part of the body’s natural plan to ensure a successful adult life so myelination is postponed until these adolescent years. As Dobbs states, “It can seem a bit crazy that we humans don’t wise up a bit earlier in life. But if we smartened up sooner, we’d end up dumber.”
Dobbs, D. Beautiful brains. National Geographic. October 2011, Vol 220 Issue 4, page 37-54.
Very intriguing that being "dumb" at an early age enables us to be smarter later! It's true that the human brain doesn't fully develop until later in life; in fact, studies have shown that full maturation doesn't occur until the age of 25 (Fuller 2011). The bit about myelination is interesting, and I found another interesting reason for teen misbehaving:
ReplyDeleteZimmer (2011) conducted research about why teens enjoy risk-taking and pleasure-seeking more than adults. Two areas of the brain control these sensations: the ventral striatum (which assesses the value of rewards) and the frontal gyrus (cognitive control over impulses that conflict). These two systems work together in an adult brain. In an adolescent brain, the ventral striatum (rewards system) matures faster than the control center, which explains why teens make decisions based on rewards, despite possible risks.
I'm curious about whether such evidence of immature brain function will ever hold in court. Will there ever be a time when juveniles receive lighter sentences due to brain underdevelopment? Some courts do take mental retardation and other brain development disorders into account when determining a conviction. However, society as a whole is generally less understanding about juvenile delinquency than delinquency in adults due to mental disorders (psychopathy being a major exception).
Many people believe that adolescents having an underdeveloped brain is not an excuse for poor behavior, and that they should be punished or rehabilitated, if need be. Does this also hold true with adults who have underdeveloped brains? Should a 25-year-old person with trisomy syndrome be charged with a sexual offense because (s)he was walking naked around a neighborhood with children? What about a teenager who commits petty theft?
After you brought up the distinctions between the teenage brain and the adult brain, I thought about another distinction that many have probably joked about but never seriously researched: biological differences between the male and female brain. According to neurophysiologist Dr. Renato Sabbatini, there are numerous anatomical differences in the brain of the two sexes, including a larger inferior-parietal lobule (abbreviated IPL, part of the cortex) found in men. Interestingly enough, the IPL has been found to be larger in some famous physicists and mathematicians, including Albert Einsten. The implication, therefore, is that IPL is a measure of a person’s mathematical aptitude. Another interesting finding is that the two regions in the frontal and temporal lobes of the human brain (called the Broca and Wernicke) are generally larger in women than man. Both the Broca and Wernicke regions are associated with language skill development—thus potentially explaining why women tend to have greater mastery of language-based mental processing (like poetry).
ReplyDeleteWe all know, however, that correlation does not necessarily mean causation. Thus, I am reluctant to deduce that a larger mass of brain tissue in different sexes causes a certain socio-behavioral pattern—it might simply be correlated with it. To learn more about the differences, visit my source:
http://www.cerebromente.org.br/n11/mente/eisntein/cerebro-homens.html
When I saw this article, it brought to mind the increased risk of alcohol related deaths in teenagers and how the development of the adolescent brain could be the cause. Pleasure-seeking and peer pressure are clearly key factors in a teen's decision to use alcohol and engage in additional risky behaviors.
ReplyDeleteI found another article that explored alcohol use in academically gifted adolescents. I hadn't considered that although some gifted students may have protective factors that decrease their likelihood of alcohol use (such as familial support), they are also at an increased risk to compensate for the social stigma bestowed upon them (Peairs 1). During the pivotal years of self-identification, gifted students may be labeled and isolated from their peers, leading them to associate with delinquents and other outcast individuals. Until the age of 13, intellectual prowess is seen as an advantage, but that advantage disappears in high school (Peairs 2). Factors such as popularity and being a leader in sports or other activities become more important to peer groups, causing these once accepted students to feel rejected.
Despite this perceived stigma, the study found that gifted students were less likely to have tried alcohol than non-gifted students. Another conclusion was that gifted adolescents who used alcohol reported having more friends, in contrast to non-gifted adolescents who used alcohol. This proposes that the reason for using alcohol is different for gifted vs. non-gifted students. While non-gifted students may be more maladjusted and prone to alcohol use, gifted students treat alcohol use as a way to gain social acceptance.
Academic Giftedness and Alcohol Use in Early Adolescence.
Peairs KF, Eichen D, Putallaz M, Costanzo PR, Grimes CL.
Gift Child Q. 2011 Apr 1;55(2):95-110.
I kind of agree with Ashton in saying that we need to look at the outward effects of this type of development (or so lack thereof) and the social implications that surround the underdeveloped mind of teenagers.
ReplyDeleteShould laws be constructed differently due to this new finding? If as Elizabeth said, teenagers are more likely to take risks, should driving ages be increased in order to promote safety of all drivers on the road? And what about the effects of alcohol; if young adults (aka 21 year-olds) are not fully developed, then should we allow them to purchase a substance that will lower their already underdeveloped brains? I think evidence definitely has some very important social implications that need to be considered.
But going back to physiological points, while we can prove that the brain is not fully developed at a certain age, what about individual differences among people? In order to really evaluate the effects of the underdeveloped brain, we would need to measure individuals to look at how far their cognition is along in regards to the "norm".
I think that this research is not only interesting, but also hold true in terms of cognition. However, it is also a little scary because we have to look at the implications of this research.
In regards to the legality of teenagers willing to use the “PFC (Prefontal Cortex)” defense, Jessica Hamzelou writes a journal article in the New Scientist speaking towards such occurrences. In a study she cites from Vanderbilt University, she illustrates that between 2004 and 2009 some 16% of defendants introduced brain scans in an attempt to diminish sentences. In light of this, she goes on to indicate that even lawyers and scientists understand that a developing brain can cause rash decision-making. However, there has been no legal precedent set as to what age the pre-frontal cortex stops developing. In reality, the brain is constantly plastic and changes throughout adulthood. From a legal point of view, the age of criminal responsibility is the hotly debated topic in this blog and the legal world. From the perspective of the article previously mentioned, Hamzelou agrees that a sliding scale should used in determining mental maturity. It is likely that brain scan in legal cases will continue to be presented until the Supreme Court receives a case to set a legal precendent in regards to using prefrontal cortex as a defense against adolescent crimes.
ReplyDelete