9.3 Thinking, Fast and Slow

Body changes in adolescence are dramatic, but even more life-changing are the intellectual advances during adolescence. Teenagers no longer think like children, but they do not yet think like adults. We begin with the neurological changes of adolescence, and then explore the cognitive and social factors that maturation brings.

Brain Development

Like the other parts of the body, different parts of the brain grow at different rates (Blakemore, 2008). The limbic system, including the amygdala (where intense fear and excitement originate) matures before the prefrontal cortex (where planning, emotional regulation, and impulse control occur). As a result, the instinctual and emotional areas of the adolescent brain develop ahead of the reflective, analytic areas. Furthermore, pubertal hormones target the amygdala directly, whereas the cortex responds more to age and experience than to hormones. These neurobehavioural changes have been linked with youths’ increased behaviours in risk taking, sensation seeking, and recklessness (Dahl, 2004).

This is evident via brain scans. Emotional control, revealed by fMRI studies, is not fully developed until adulthood (Luna et al., 2010). When compared with 18- to 23-year-olds, 14- to 15-year-olds show heightened arousal in the brain’s reward centres, making them seek excitement and pleasure (van Leijenhorst et al., 2010).

Caution NeededThe fact that the frontal lobes (prefrontal cortex) are the last to mature may explain something that has long bewildered adults: Many adolescents are driven by the excitement of new experiences and sensations—forgetting the caution that their parents have tried to instill (Steinberg, 2008).

Laurence Steinberg is a noted expert on adolescent thinking. He is also a father.

Same People, But Not the Same Brain These brain scans are part of a longitudinal study that repeatedly compares the proportion of grey matter from childhood through adolescence. Grey matter is reduced as white matter increases, in part because pruning during the teen years (the last two pairs of images here) allows intellectual connections to build. As the authors of one study that included this chart explain, teenagers may “look like an adult, but cognitively they are not there yet” (K. Powell, 2006).

NITIN GOGTAY ET AL./NATIONAL ACADEMY OF SCIENCES, USA

Steinberg agrees with his son. As he expresses it, “The problem is not that Ben’s decision-making was deficient. The problem is that it was nonexistent” (Steinberg, 2004). Steinberg points out a characteristic of adolescent thought: When emotions are intense, especially when friends are nearby, the logical part of the brain shuts down.

This neurological shutdown is not reflected in questionnaires that ask teenagers to respond to hypothetical dilemmas. On those tests, most teenagers think carefully and answer correctly. They have been taught the risks of sex and drugs in biology or health classes in school, and they circle the right answers on multiple-choice tests. However,

Brain immaturity is not the origin of every “troublesome adolescent behavior,” but it is true that teenage brains have underdeveloped “response inhibition, emotional regulation, and organization” (Sowell et al., 2007) because their prefrontal cortexes are immature.

The normal sequence of brain maturation (limbic system at puberty, then prefrontal cortex by the earlier 20s) combined with the early onset of puberty means that, for contemporary teenagers, emotions rule behaviour for years (Blakemore, 2008). The limbic system, unchecked by the slower-maturing prefrontal cortex, makes powerful sensations—loud music, speeding cars, strong drugs—compelling.

It is not that the prefrontal cortex shuts down completely. In fact, it continues to mature throughout childhood and adolescence, and, when they think about it, adolescents are able to assess risks better than children are (Pfeiffer et al., 2011). However, when they think about it is crucial. The thoughtful parts of the adolescent brain are less synchronized with the limbic system than they were earlier in life, and thus emotions from the amygdala are less modulated than they once were (Pfeiffer et al., 2011). The balance and coordination among the various parts of the brain is off-kilter, not the brain itself (Casey et al., 2011).

Same Situation, Far Apart: Danger Ahead They may be far apart in culture, but both think like the teenagers they are. Jumping from a bridge in Bangladesh, he ignores the risk; at the wheel in North America, she ignores the road.

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When stress, arousal, passion, sensory bombardment, drug intoxication, or deprivation is extreme, the adolescent brain is flooded with impulses. Teenagers brag about being so drunk they were “wasted,” “bombed,” “smashed”—a state most adults try to avoid and would be ashamed to admit. Unlike adults, some teenagers choose to spend a night without sleep, go through a day without eating, exercise in pain, or play hockey after a mild concussion.

Risk and RewardEvery decision, from whether to eat a peach to when and where to enrol in college or university, requires balancing risk and reward, caution and attraction. For everyone, experiences, memories, emotions, and the prefrontal cortex help in choosing to avoid some actions and perform others. Neurological research finds that the reward parts of adolescents’ brains (the parts that respond to excitement and pleasure) are far stronger than the inhibition parts (the parts that urge caution) (Van Leijenhorst et al., 2010). The parts of the brain dedicated to analysis may be immature until years after the first hormonal rushes and sexual urges.

With regard to risk, by far the most common cause of teenage death is automobile accidents, and this is true despite teens having quicker reflexes and better vision than older people. A Statistics Canada report notes that of all the Canadians who were killed in motor-vehicle accidents over one five-year period, almost one-quarter (24 percent) were aged 15 to 24 (Statistics Canada, 2012d).

Thoughtless impulses and poor decisions, rather than problems with reflexes or vision and hearing, are almost always to blame for these accidents. A major problem today is teens texting and talking on cellphones while driving. This has become such a problem in Canada that six provinces—Newfoundland and Labrador, Nova Scotia, Quebec, Ontario, British Columbia, and Saskatchewan—have passed laws restricting hand-held cellular phone use while driving. In addition, Transport Canada recommends a total ban on cellphone use by drivers (Huang et al., 2010).

Extensive research reveals that four measures have saved hundreds of lives of teenage drivers: (1) requiring more time between issuing a learner’s permit and granting a full licence, (2) no driving at night, (3) no teenage passengers, and (4) a zero-alcohol policy for young drivers (Fell et al., 2011).

Thinking About Oneself

During puberty, young people focus on themselves, in part because maturation of the brain heightens self-consciousness (Sebastian et al., 2008). It is typical for young adolescents to think deeply (but not always realistically) about their own emotions about adults, education, friends, and the future. One reason adolescents spend so much time talking on the phone, emailing, and texting is that they like to ruminate about each nuance of whatever they have done, might have done, and could do: “He said, she said, and I should’ve said.”

EgocentrismYoung adolescents not only think intensely about themselves, they also think about what others think about them. Together, these two aspects of thought are called adolescent egocentrism, first described by David Elkind (1967). Egocentrism dominates in early adolescence, but it appears at times throughout the teen years, especially when the young person enters a new school or new peer group or goes off to college or university.

Look at Me Egocentrism can cause teenagers to dye their hair blue, wax their eyebrows, or wear a checked shirt over stripes to call attention to themselves.

PICTURE PARTNERS/ALAMY

In egocentrism, adolescents regard themselves as unique, special, and much more socially significant (i.e., noticed by everyone) than they actually are. Egocentrism creates an imaginary audience in the minds of many adolescents. They believe they are at centre stage, with all eyes on them, and they imagine how others might react to their appearance and behaviour. The imaginary audience can cause teenagers to enter a crowded room as if they are the most attractive human beings alive. Take the case of Edgar, as described by his older sister:

The reverse is also possible: Unlike with Edgar, egocentrism might cause adolescents to avoid scrutiny lest someone notice a blemish on their chin or make fun of their braces.

Egocentrism also leads adolescents to interpret everyone else’s behaviour as if it were a judgment on them. A stranger’s frown or a teacher’s critique could make a teenager conclude that “No one likes me” and then deduce that “I am unlovable” or even to claim that “I can’t leave the house.” More positive casual reactions—a smile from a sales clerk or an extra-big hug from a younger brother—could lead to “I am great” or “Everyone loves me,” with similarly distorted self-perception. Given the rapid mood changes of adolescence, such conclusions are usually short-lived and susceptible to reversal with another offhand remark.

Elkind named several aspects of adolescent egocentrism, including the personal fable and the invincibility fable, which often appear together (Alberts et al., 2007). The personal fable is the belief that one is unique and destined to have a heroic, fabled, even legendary life. Some 12-year-olds plan to star in the NBA, or become billionaires, or cure cancer. In some adolescent minds, there is no contradiction between the personal fable and invincibility, the idea that, unless fate wills it, they will not be hurt by fast driving, unprotected sex, or addictive drugs. If they take risks and survive without harm, they feel invincible, not relieved.

Formal Operational Thought

In his theory of cognitive development, Jean Piaget described a shift in adolescence from concrete operational thought to what he called formal operational thought. Adolescents begin to consider abstractions and can make “assumptions that have no necessary relation to reality” (Piaget, 1972).

One way to distinguish formal from concrete thinking is to compare curricula in primary school and high school. For example in math, younger children multiply real numbers, such as 4 × 3 × 8; adolescents multiply abstract (algebraic) numbers, such as (2x)(3y) or (25xy²)(3zy³). In social studies, younger children learn about other cultures by reading about daily life or experiencing aspects of the culture themselves—drinking goat’s milk or building an igloo, for instance. Adolescents can hypothesize how gross national product and fertility rate might affect global politics.

Piaget’s ExperimentsPiaget and his colleagues devised a number of tasks to assess formal operational thought (Inhelder & Piaget, 1958). In one experiment (diagrammed in Figure 9.2), children of many ages balance a scale by hooking weights onto the scale’s arms. To master this task, they must realize that the weights’ heaviness and distance from the centre interact reciprocally to affect balance.

FIGURE 9.2 How to Balance a Scale Piaget’s balance-scale test of formal reasoning, as it is attempted by (a) a 4-year-old, (b) a 7-year-old, (c) a 10-year-old, and (d) a 14-year-old. The key to balancing the scale is to make weight times distance from the centre equal on both sides of the centre; the realization of that principle requires formal operational thought.

The concept of balancing (that a heavy weight close to the centre could be balanced by a lighter weight farther from the centre on the other side) was completely beyond the 3- to 5-year-olds. By age 7, children could balance the scale by putting the same amount of weight on each arm, but they didn’t realize that the distance from the centre mattered. By age 10, children thought about location, but used trial and error, not logic. Finally, by about age 13 or 14, some children hypothesized and tested the reciprocal relationship between weight and distance and developed the correct formula (Piaget & Inhelder, 1969). In all of Piaget’s experiments, “in contrast to concrete operational children, formal operational adolescents imagine all possible determinants…[and] systematically vary the factors one by one, observe the results correctly, keep track of the results, and draw the appropriate conclusions” (P. H. Miller, 2011).

Scientific Reasoning Jordan Hikowitz, also known as Doctor Mad Science, is an 11-year-old science sensation from Richmond Hill, Ontario. He conducts experiments, films them, and posts them online for millions to view. Here, he creates a liquid lava lamp.

LUCAS OLENIUK/TORONTO STAR VIA GETTY IMAGES

Hypothetical-Deductive ReasoningOne hallmark of formal operational thought is the capacity to think of possibility, not just reality. “Here and now” is only one of many alternatives, including “there and then,” “long, long ago,” “nowhere,” “not yet,” and “never.” As Piaget said:

Adolescents are primed to engage in hypothetical thought, reasoning about if–then propositions that do not reflect reality. For example, consider this question (adapted from De Neys & Van Gelder, 2009):

Younger adolescents often answer “No!” They know that whales swim, not walk, so the logic escapes them. Some adolescents answer “Yes.” They understand the concept of if:

In developing the capacity to think hypothetically, adolescents gradually become capable of deductive reasoning, or top-down reasoning. Deductive reasoning begins with an abstract idea and then uses logic to draw specific conclusions (Galotti, 2002; Keating, 2004). By contrast, during the primary school years, children accumulate facts and personal experiences (the knowledge base), asking what and why. The result is inductive reasoning, or bottom-up reasoning, with many specific examples leading to general conclusions (see Figure 9.3).

FIGURE 9.3 Bottom Up or Top Down? Children, as concrete operational thinkers, are likely to draw conclusions on the basis of their own experiences and what they have been told. This is called inductive, or bottom-up, reasoning. Adolescents can think deductively, from the top down.

Two Modes of Thinking

The fact that adolescents and adults can use hypothetical-deductive reasoning does not necessarily mean that they do use it (Kuhn & Franklin, 2006). Adolescents particularly find it much easier and quicker to forget about logic and instead to follow their impulses.

In adolescence, abstract logic is counterbalanced by the increasing power of intuitive thinking. A dual-process model of adolescent cognition has been formulated (Albert & Steinberg, 2011). Various scholars choose different terms and sometimes distinct definitions of the two processes of thinking, such as: intuitive and analytic, implicit and explicit, creative and factual, contextualized and decontextualized, unconscious and conscious, hot and cold, gist and quantitative, emotional and intellectual, experiential and rational, and system 1 and system 2.

Impressive Thinking “Correlating Genetic Signature with Surface Sugar Expression in Vibrio vulnificus” is the title of Shilpa Argade’s winning science project about a sometimes deadly bacteria. Like many other high school seniors, she is capable of deductive reasoning.

PHOTO BY JOHN GIBBINS, SAN DIEGO UNION-TRIBUNE/ZUMA PRESS © 2009

The thinking described by the first half of each pair (intuitive, implicit, creative, contextualized, unconscious, hot, gist, emotional, experiential, system 1) is preferred in everyday life. Sometimes, however, circumstances and experience compel people to use the second mode, when deeper thought is demanded. Because of the discrepancy between the maturation of the limbic system and the prefrontal cortex, adolescents are particularly likely to use intuition, not analysis (Gerrard et al., 2008). Intuitive thought begins with a belief, assumption, or general rule (called a heuristic) rather than with logic. Intuition is quick and powerful; it feels “right.” Analytic thought is the formal, logical, hypothetical-deductive thinking as described by Piaget. It involves rational analysis of many factors whose interactions have to be calculated, as in the scale-balancing problem.

When the two modes of thinking conflict, people sometimes use one mode and sometimes the other. Experiences and role models influence the choice. For example, one study found that when adolescents enter a multicultural high school, some rely on old stereotypes and others reassess their thoughts to consider new perspectives. Which of these two modes of thinking predominates depends on the students’ specific experiences and on the attitudes of the adults in the school (Crisp & Turner, 2011).

Comparing Intuition and AnalysisPaul Klaczynski conducted dozens of studies comparing the thinking of children, young adolescents, and older adolescents (usually 9-, 12-, and 15-year-olds) (Holland & Klaczynski, 2009; Klaczynski, 2001, 2011; Klaczynski et al., 2009). In one, he presented 19 logical problems, for example:

In ranking these statements, most adolescents (73 percent) made at least one analytic error, ranking a double statement (e.g., popular and an athlete) as more likely than a single statement included in it (popular or an athlete). They intuitively jumped to the more inclusive statement, rather than sticking to logic. In many other studies, adults often make the same mistake (Kahneman, 2011).

Klaczynski found that almost all adolescents were analytical and logical on some of the 19 problems but not on others. Logical thinking improved with age and education, although not with IQ. In other words, being smarter as measured by an intelligence test did not advance logic as much as did having more experience, in school and in life. Klaczynski (2001) concluded that, even though teenagers can use logic, “most adolescents do not demonstrate a level of performance commensurate with their abilities” (p. 854).

Robot Competition This robot is about to compete in the Annual Robotics Olympic challenge in Dresden, Ontario. Breanne, a 14-year-old from Chatham, Ontario, designed this robot to compete in a number of activities such as steeple chase, relay races, and weightlifting.

BOB BOUGHNER/CHATHAM DAILY NEWS/QMI AGENCY

Preferring EmotionsWhat would motivate adolescents to use—or fail to use—their formal operational thinking? Klaczynski’s participants had all learned the scientific method in school, and they knew that scientists use empirical evidence and deductive reasoning. But they did not always think like scientists. Why not?

Dozens of experiments and extensive theorizing have found some answers (Albert & Steinberg, 2011; Kahneman, 2011). Essentially, analytic thought is more difficult than intuition, and it requires examination of comforting, familiar prejudices.

Once people of any age reach an emotional conclusion (sometimes called a “gut feeling”), they resist changing their minds. As people gain experience in making decisions and thinking things through, they become better at knowing when analysis is needed (Milkman et al., 2009).

For example, in contrast to younger students, older adolescents are more suspicious of authority and more likely to consider mitigating circumstances when judging the legitimacy of a rule (Klaczynski, 2011). Both suspicion of authority and awareness of context signify advances in reasoning, but both also complicate simple issues.