21.3 Selective Gains and Losses

Aging neurons, cultural pressures, historical conditions, and past education all affect adult cognition. None of these can be controlled directly by an individual adult. Nonetheless, many researchers believe that adults make crucial choices about their intellectual development.

For example, why have number skills declined more for recent cohorts than for earlier ones? The reason may not be past math curricula (as was suggested) but rather modern adults’ reliance on calculators instead of paper-and-pencil (or mental) calculations. If adults decided to trash their calculators, their math skills might improve. Of course, most adults would consider that strange: Spending more time on math might help number skills, but few modern adults want to do double-digit division in their heads.

Similarly, memory would improve if we did not use directories and speed dial to phone or text our friends. But do the cultural artifacts of modern life make us lazy intellectually? Or have people merely focused on new challenges?

Accumulating Stressors

Many health decisions that adults make prioritize immediate comfort over long-term health. That impairs cognition because anything that slows down blood circulation slows down the brain. That affects speed of thought and leads to brain shrinkage. Drug abuse, high blood pressure, diabetes, obesity, alcoholism, lack of exercise, and cigarette smoking—all chosen by many adults—impair thought.

Now we focus on another factor that slows down cognition: stress. Every life is stressful. Some stresses become stressors. A stressor is an experience, circumstance, or condition that affects a person. Thus a stress is external; if stresses are internalized, they become stressors.

Between ages 25 and 65, family members die, disasters destroy homes, jobs disappear, and even welcome events—a new marriage, birth, or job, for instance—cause stress. In addition, daily life is filled with minor stresses called hassles—traffic jams, spilled food, noise at night, rude strangers, aches and pains, dirty pots, and much more. Daily hassles and major stresses can become stressors, destroying health.

If organ reserves are depleted, the physiological toll of stress can lower immunity, increase blood pressure, speed up the heart, reduce sleep, and produce many other reactions that can lead to cognitive loss as allostatic load increases. Similar to organ reserve, there is a cognitive reserve: Although the mind benefits from ongoing use, when people must suddenly perform difficult cognitive tasks they are less able to think clearly. They may make impulsive decisions, and those decisions may be destructive.

Same Situation, Far Apart: Two 2013 Disasters In the Boston marathon (left), three people were killed and more than 200 injured when a terrorist bomb exploded, and in South Africa (right), 34 striking mine workers were shot dead when police opened fire. Despite the obvious differences, survivors everywhere cope by crying and holding each other

JOHN BLANDING/THE BOSTON GLOBE VIA GETTY IMAGES
STRINGER/AFP/GETTY IMAGES

Humans have always experienced stresses, some of which becomes stressors, and they have developed ways to cope with them, sometimes with biological homeostasis and allostasis, sometimes more directly with cognitive strategies. As you will see, the choice as to which coping method to use may lead to intellectual strength or impairment.

Stressors increase all the bad habits described in Chapter 20—drug use, overeating, underexercising—sometimes ostensibly to relieve the stress but eventually making things worse. Stress does not merely correlate with illness—it causes illness. In an experiment, volunteers first indicated how stressed they felt and then agreed to have a cold virus squirted up their nostrils. A week later, some of them were stuffed, sneezing, and feverish. Others were fine. Stress was a crucial factor (S. Cohen et al., 1993).

Similarly, stress hormones not only undercut thinking in the moment, but can also reduce mental ability for the future. Stress affects more than logic; chronic stress increases depression and other psychological illnesses that impair thinking, and it attacks the brain itself (Marin et al., 2011; McEwen & Gianaros, 2011).

Reactions to stress can cause yet more stress, which means that stressors accumulate. For example, a longitudinal study of married couples in their 30s found that if the husband’s health deteriorated, the chance of divorce increased. Thus one reaction to the stress of illness was to do something that increased stress. This effect was apparent with all couples, particularly for well-educated European Americans (Teachman, 2010).

The rate of divorce also increases when parents have children with special needs (Price, 2010). Conversely, for some couples having a child with serious problems brings partners closer together (Solomon, 2012). Apparently having a child with special needs is always stressful, and thus creates a stressor. But how people then cope with that stressor is crucial to their mental health.

Coping involves cognition because people choose what to do. Abuse of alcohol and other drugs is one form of avoidant coping. Ignoring a problem, either literally forgetting it or hiding it (one person who owed back taxes threw all official letters under his bed, unopened), is the worst way of coping—it increases depression and the risk of suicide.

Psychologists distinguish two positive ways of coping with stress. In problem-focused coping, people attack the stressor directly—for instance, by confronting a difficult boss, or by moving out of a noisy neighborhood. In emotion-focused coping, people try to change their emotional reactions—for instance, from anger to acceptance, making the stressor disappear and becoming stronger and more empathic because of it. Many adults who work to help others (therapists, human service workers, teachers) do so because of their own past experiences in overcoming serious stress.

Biologically and culturally, the two sexes may respond differently to stress. Men tend to be problem-focused, reacting in a “fight-or-flight” manner. Their sympathetic nervous system (faster heart rate, increased adrenaline) prepares them for attack or escape. Their testosterone level rises when they confront a problem and decreases if they fail. From childhood, boys are encouraged to fight back, and adult men are more likely to rage openly, use force, or disappear.

Women, however, are more emotion-focused and are likely to “tend and befriend”—that is, to seek the company of other people when they are under pressure. Their bodies produce oxytocin, a hormone that leads them to seek confidential and caring interactions (S. E. Taylor, 2006; S. E. Taylor et al., 2000). Their first reaction when something goes wrong is to call a friend.

This gender difference in coping explains why a woman might get upset if a man doesn’t want to talk about his problems and why a man might get upset if a woman just wants to talk instead of taking action. Both problem- and emotion-focused coping can be effective; everyone should sometimes fight and sometimes befriend.

Not only do people need to figure out the best strategy to deal with each particular problem, but they also need to figure out when other people will help and when they will not (Aldwin, 2007). Getting social support is generally a good strategy—other people provide suggestions, lighten a load, and add humor or perspective (Fiori & Dencklar, 2012). But sometimes other people criticize, distract, or delay a person’s coping.

The best coping strategy depends on the situation. Worse than either problem-or emotion-focused coping is no strategy—denying a problem until it escalates or takes a physical toll, such as causing high blood pressure, digestive difficulties, or even a heart attack. Avoidance causes homeostasis and allostatic load. [Lifespan Link: Homeostatis and allostatic load were discussed in Chapter 17.]

The stress that a person endures in childhood and adolescence may become evident in morbidity during the adult years. A U.S. study of 65,000 adults compared many signs of poor health, such as hypertension and insulin resistance. The gradual accumulation of such biochemical stressors is called weathering, and this study found that weathering happened faster among African Americans—by age 60 their average biological age was 10 years older than that of European Americans. The authors believe this was the result of the “chronic stress” of living in a “race-conscious society” (Geronimus et al., 2006, p. 832). Social support?

The average life span of African American adults is about 4 years shorter than that of European Americans until about age 80, when some data find a “cross over,” with African Americans living longer. Curiously, Latinos live longer than either group (National Center for Health Statistics, 2013). Social support?

Weathering has a direct impact on intelligence. In studies conducted in the United States in the 1980s, the average IQ score of African Americans was 15 points lower than the average score for European Americans (Neisser et al., 1996). Earlier researchers hypothesized that these differences were genetic. However, later research suggests that stress may be the cause. Specifically:

1. The Black–White IQ gap narrowed, from about 15 points to about 10 between 1972 and 2002 (Dickens & Flynn, 2006) and continues to shrink—more in some abilities than others.
2. The racial differences are apparent in vocabulary but not in learning abilit (Fagan & Holland, 2007).
3. The racial differences are less dramatic at age 4 and most dramatic at about age 25.

All three of these findings suggest that stress may reduce the IQ of African Americans. Note that the IQ gap is most evident in early adulthood.

Ideally, with age and experience adults learn to respond wisely. Over the years of adulthood, a more positive attitude toward life develops, which makes it easier to reinterpret stresses so that they do not fester (Charles & Carstensen, 2010). Often,

VISUALIZING DEVELOPMENT

Stress in Adulthood

Stresses and coping strategies differ from generation to generation. Developmentalists believe that emerging adults today may have more stresses than in the past because education is increasingly important and unemployment is higher. However, adults without jobs or supportive families may be more stressed than emerging adults since they feel more responsible for their problems. Fortunately, the ability to cope may improve with age.

Just as there are many ways to cope with stress, there are many ways to measure it. One common one is to simply ask people what stresses them and another way is experience sampling-(beeping people at random times to find out what they are doing and feeling at the moment). As you see from the charts below, the results may differ.

WHAT CAUSES STRESS IN DAILY LIFE

Depending on exactly how the question is phrased, adults identify different triggers for their daily stress. For many, it is work, family, health, and safety concerns that worry them.

For people of every background, age brings another advantage. Emerging adulthood is “a time of heightened hassles.” Once life settles down, some stresses (dating, job hunting, moving) occur less frequently. Adults “are more adept at arranging their lives to minimize the occurrence of stressors” (Aldwin, 2007, p. 298). (Visualizing Development, p. 618, compares stress in different age groups.)

Remember that attitude sometimes determines whether or not an event becomes a stressor, and whether that stressor decreases over time. For instance, post-traumatic stress disorder (PTSD) is a common response to combat, especially if the person suffering the disorder saw others seriously wounded or killed. The stressor can continue long after the stressful event. That is one explanation for a surprising statistic: In 2012 more U.S. soldiers died of suicide (349, often after coming home) than died in battle in Afghanistan (245). But most veterans readjust well; less than half of those with combat experience develop PTSD.

Some people respond to their stressors with religious coping, believing that there is some divine purpose for the problem. Social scientists find that religious coping is particularly likely when people have unexpected illnesses or disasters. As with other forms of coping, sometimes religious coping mitigates a stressor, other times it makes it worse (Burke et al., 2013; Thuné-Boyle et al., 2013). During adulthood, religious faith and practice tend to increase; past experience coping with stress may be the reason.

Of course, natural disasters, such as earthquakes, and personal tragedies, such as the death of a loved one, are always stressful at the time. The surprise is that they are usually overcome, with many adults ignoring some disruption and reinterpreting events. Instead of dwelling on their misfortune, they emphasize their good fortune—not “why me?” but “it could have been worse.” Some adults reinterpret stress as challenges, not stressors, even if outsiders would consider them threats (Reich et al., 2010).

When challenges are successfully met, not only do people feel more effective and powerful, but the body’s damaging responses to stressors—increased heart and breathing rates, hormonal changes, immune system breakdowns, cognitive lapses, and so on—are averted. Indeed, effective coping may strengthen the immune system and promote health (Bandura, 1997). For adults potential stressors can become positive turning points (Reich et al., 2010), as may have happened in the following case.

A CASE TO STUDY

Coping with Katrina

Lingering Effects of Hurricane Katrina Typically, most people involved in a natural disaster recover within weeks, but as the chart shows, most Katrina victims were still feeling the psychological effects six months later. Two years after the hurricane, death rates in New Orleans from all causes, from heart attacks to homicide, were double what they had been before the storm.

Developmentalists are following the hundreds of thousands of people in Louisiana and Mississippi who were uprooted by Hurricane Katrina in 2005. Many of them lost homes and jobs, went without food and water, and knew people who died. Not surprisingly, their stressors increased. For instance, one study of survivors from New Orleans six months after the flood found that most of them had stress reactions: Almost all were irritable and had upsetting thoughts, and half had nightmares (see Figure 21.2.).

The accumulation of stressors led to many physical and psychological difficulties. One in nine suffered serious mental health problems, twice as many as before the hurricane. Another 20 percent had mild to moderate mental illness, again double the earlier rate (Kessler et al., 2006). Given the trauma of the storm (a major stress) and the inept official response (which led to ongoing hassles), this is not surprising.

However, longitudinal studies found that the same stressors also led to increased resilience, with three out of four people reporting that they found a deeper sense of purpose after Katrina. Only one person in 250 had made a plan for suicide, which was one-tenth the rate before the storm, perhaps because they no longer felt personally responsible for their depression and because others were more understanding (Kessler et al., 2006). Adults aged 40 to 65 were particularly likely to cope well with the trauma.

620

A college student who traveled to Mississippi to help survivors provides a firsthand account. She was expecting to see people defeated by their losses. In her words:

Three hundred college students from Ohio traveled to Mississippi to help survivors of Katrina. Arriving six months after the devastation, they saw rusted cars, shells of homes, and even clothing still stuck to tree branches. But they also met hundreds of people putting their lives together, including teachers at a head start program, who eagerly got back to work within a few weeks after the storm. One student was awed by the “resilient optimism rising above the rubble.” She quoted a local volunteer who said “You make a living with what you earn; you make a life with what you give.”

[Feerasta, 2006]

Although the actual hurricane occurred years ago, those who experienced it continue to cope with the aftermath. Social scientists continue to study them. One team considered religious beliefs before and after Katrina. Those caught in Katrina who believed that God is vengeful and punishing were more likely to suffer, but those who believed that God is caring and benevolent coped well, experiencing post-traumatic growth, not PTSD (Chan & Rhodes, 2013).

Humans seem to have a recovery reserve that is activated under stress, similar to the organ reserve explained in Chapter 17. According to a related set of studies, it seems that extra effort and alertness are summoned when emergencies arise, even if those affected are overtired and in a noisy environment. This reserve works well for the moments of the emergency, especially if people feel there is something they can do. No wonder the teachers in New Orleans after Katrina wanted to get back to work.

This may explain a familiar reaction to final exams: Some students study intensely, perform well … and then collapse, maybe even getting sick after their last exam. More research is needed, but it seems possible that adults gradually develop better coping methods to adapt to the vicissitudes of life (Masten & Wright, 2010; Aldwin & Gilmer, 2013).

Optimization with Compensation

Paul and Margret Baltes (1990) developed a theory called selective optimization with compensation to describe the “general process of systematic function” (P. B. Baltes, 2003, p. 25) by which people maintain a balance in their lives as they grow older. They believe that people seek to optimize their development, selecting the best way to compensate for physical and cognitive losses, becoming more proficient at activities they want to perform well.

Selective optimization with compensation applies to every aspect of life, ranging from choosing friends to playing baseball. Each adult seeks to maximize gains and minimize losses, practicing some abilities and ignoring others. Choices are critical, because any ability can be enhanced or diminished, depending on how, when, and why a person uses it. It is possible to “teach an old dog new tricks,” but learning requires that adults want to learn those new tricks.

When adults are motivated to do well, few age-related deficits are apparent. However, compared with younger adults, older adults are less motivated to put forth their best effort when the task at hand is not particularly engaging (Hess et al., 2009). That works against them if they take an IQ test.

As Baltes and Baltes (1990) explain, selective optimization means that each adult selects certain aspects of intelligence to optimize and neglects the rest. If the ignored aspects happen to be the ones measured on intelligence tests, then IQ scores will fall, even if the adult’s selection improves (optimizes) other aspects of intellect. The brain is plastic over the entire life span, developing new dendrites and activation sequences, adjusting to whatever the person chooses to learn (Smith & Baltes, 2013; Karmiloff-Smith, 2010; Macdonald et al., 2009).

For example, suppose someone who is highly motivated to learn about a particular area of the world (perhaps the Rocky Mountains) notices that aging affects his or her vision, making it hard to read fine print. That person might get reading glasses, increase computer type size (compensation), and read closely every article about the Rockies, ignoring news articles about everything else (selectivity). If an IQ vocabulary item happened to be avalanche, the person might score correctly, but he or she would fail most questions of general knowledge. In that way, knowledge increases (optimization) in depth but decreases in breadth.

Focus It might seem as if Cindy Fay, shown here, has too many distractions to get anything done, but this scene actually depicts her intense, productive focus. She is a meteorologist for the National Weather Service, predicting the weather in the next 24 hours in Hastings, Nebraska. The monitors, phones, keyboards, and notes on her expansive desk are all carefully selected to optimize her forecasting ability.

©RYAN MCGINNIS/ALAMY

One example of selective optimization is multitasking, which becomes more difficult with every passing decade (Reuter-Lorenz & Sylvester, 2005). Actually, multitasking slows down everyone of every age, but awareness of the slowdown is more acute with age.

This fact is obvious when people drive a car while talking on a cell phone. Such behavior is particularly dangerous for older drivers because as the brain focuses on the conversation, the neurological shift needed to react to a darting pedestrian is slower (Asbridge et al., 2013). Some jurisdictions require drivers to use hands-free phones, as if the distraction originates in the arms. These misguided laws have not reduced traffic accidents resulting from cell phone use because the multitasking brain is the problem, not the arms.

Some say that passenger conversation is as distracting as cell phone talk, but that is not true: Years of practice have taught adult passengers (though not young children) when to stop talking so that the driver can focus on the road (S. G. Charlton, 2009). If passengers do not quiet down on their own, experienced drivers stop listening and replying because they know they must concentrate.

This is why statements such as “I can’t do everything at once” and “Don’t rush me” are more often said by older adults than teenagers. Adults compensate for slower thinking by selecting one task at a time. Resources within the brain are increasingly limited with age, but compensation allows optimal functioning (Freund, 2008).

One father tried to explain this concept to his son as follows:

Expert Cognition

Another way to describe gains and losses is to say that everyone develops expertise, becoming a selective expert, specializing in activities that are personally meaningful, anything from car repair to gourmet cooking, from illness diagnosis to fly fishing. As people develop expertise in some areas, they pay less attention to others. For example, each adult usually elects to watch just some channels on television and ignoring vast realms of experience. Each adult has no interest in attending certain events for which others wait in line for hours.

Same Situation, Far Apart: Don’t Be Afraid The police officer in Toronto collecting slugs and the violinist in Jakarta collecting donations have both spent years refining their skills. Many adults would fear being that close to a murder victim, or that close to thousands of rushing commuters, but both these men have learned to practice their vocation no matter where they are. They are now experts: the cop discovered that two guns were used, and this musician earns more than $5 a day (the average for street musicians in Indonesia).

COLIN MCCONNELL/TORONTO STAR VIA GETTY IMAGES
ADEK BERRY/AFP/GETTY IMAGES

Culture and context guide us in selecting areas of expertise. Many adults born 60 years ago are much better than more recent cohorts at writing letters with distinctive and legible handwriting. In childhood they practiced penmanship, became expert in it, and maintained that expertise. Today’s schools and, consequently, children make other choices: Reading, for instance, is now crucial for every child, unlike a century ago when adult illiteracy was common.

Experts, as cognitive scientists define them, are not necessarily people with rare and outstanding proficiency. Although sometimes the term expert connotes an extraordinary genius, to researchers it means more—and less—than that. Expertise is not innate, although people with inherited abilities often select those abilities to develop.

An expert is not simply someone who knows more or who is talented in a particular way. That is only the beginning. At a certain point, accumulated knowledge, practice, and experience become transformative, putting the expert in a different league from others. The quality as well as the quantity of cognition is advanced. Expert thought is (1) intuitive, (2) automatic, (3) strategic, and (4) flexible, as we now describe.

Novices follow formal procedures and rules. Experts rely more on past experiences and immediate contexts; their actions are therefore more intuitive and less stereotypic than those of the novice. The role of experience and intuition is evident, for example, during surgery. Outsiders might think medicine is straightforward, but experts understand the reality:

In one study, many surgeons saw the same videotape of a gallbladder operation and were asked to talk about it. The experienced surgeons anticipated and described problems twice as often as did the residents (who had also removed gallbladders, just not as many) (Dominguez, 2001). Data on physicians indicate that the single most important question to ask a surgeon is, “How often have you performed this operation?” The novice, even with the best, most recent training, is less skilled than the expert.

This is true in psychotherapy as well, according to a study that compared novices and experts—all with the requisite academic knowledge. The therapists were asked to talk aloud as they analyzed a hypothetical case. The experts did more “forward thinking,” using inferences and developing a possible treatment plan. The novices were less likely to think about the social relationships of the person, and more likely to stick to a description of what is rather than wonder about what might be (Eells et al., 2011).

Another example of expert intuition is chicken-sexing—the ability to tell whether a newborn chicken is male or female. As David Myers (2002) tells it:

If You Don’t Know, Don’t Think! Undergraduates at the University of Amsterdam were asked to predict winners of four World Cup soccer matches in one of three conditions: (1) immediate—as soon as they saw the names of the nations that were competing in each of the contests, (2) conscious—after thinking for two minutes about their answers, and (3) unconscious—after two minutes of solving distracting math tasks. As you can see, the experts were better at predicting winners after unconscious processing, but the nonexperts became less accurate when they thought about their answers, either consciously or unconsciously.

One experiment that studied the relationship between expertise and intuition involved 486 college students who were asked to predict the winners of soccer games not yet played. The students who were avid fans (the experts) made better predictions when they had a few minutes of unconscious thought instead of when they had the same number of minutes to mull over their choice (see Figure 21.3). Those who didn’t care much about soccer (the nonexperts) did worse overall, but they did especially poorly when they had time to use unconscious intuition (Dijksterhuis et al., 2009).

The details of this experiment are intriguing. For 20 seconds, all participants were shown a computer screen with four soon-to-be-played soccer matches and were asked to predict the winners. One-third of the predictions were made immediately, one-third were made after two minutes of conscious thought, and one-third were made after two minutes when only unconscious thought could occur—because people randomly assigned to that group were required to calculate a series of mind-taxing math questions during those two minutes.

Nonexperts did no better than chance. They did worse after thinking about their answer, especially when the thought was unconscious. Perhaps the stress of doing math interfered with their thinking. By contrast, the predictions of the experts were not much better than those of the nonexperts when they guessed immediately, a little better when they had two minutes to think, and best of all after unconscious thought. Apparently, the experts’ knowledge of soccer helped them most when they were consciously thinking of something else.

This experiment with soccer experts and nonexperts also confirms that many elements of expert performance are automatic; that is, the complex action and thought required by most people have become routine for experts, making it appear that most aspects of the task are performed instinctively. Experts process incoming information quickly, analyze it efficiently, and then act in well-rehearsed ways that make their efforts appear unconscious. In fact, some automatic actions are no longer accessible to the conscious mind.

For example, adults are much better at tying their shoelaces than children are (adults can do it in the dark), but they are much worse at describing how they do it (McLeod et al., 2005). When experts think, they engage in “automatic weighting” of various unverbalized factors. This automatic thinking can be disrupted by the words that nonexperts use, which distort rather than clarify the thinking process (Dijksterhuis et al., 2009, p. 1382).

This is apparent if you are an experienced driver and try to teach someone else to drive. Excellent drivers who are inexperienced instructors find it hard to recognize or verbalize things that have become automatic—such as noticing pedestrians and cyclists on the far side of the road, or feeling the car shift gears as it heads up an incline, or hearing the tires lose traction on a bit of sand. Yet such factors differentiate the expert from the novice.

This may explain why, despite powerful motivation, quicker reactions, and better vision, teenagers have three times the rate of fatal car accidents as adults do (Insurance Institute, 2012). Sometimes teenage drivers deliberately take risks (speeding, running a red light, drinking, and so on), but they more often simply misjudge and misperceive conditions that a more experienced driver would automatically notice.

The same gap between knowledge and instruction occurs when a computer expert tries to teach a novice what to do, as I know myself when my daughters try to help me with the finer points of Excel. They are unable to verbalize what they know, although they can do it very well with the computer. It is much easier to click the mouse or do the keystroke oneself than to teach what has become automatic.

Automatic processing is thought to explain why expert chess and Go players are much better than novices. They see a configuration of game pieces and automatically encode it as a whole, rather than analyzing it bit by bit.

A study of expert chess players (aged 17 to 81) found minor age-related declines, but expertise was much more important than age. This was particularly apparent for speedy recognition that the king was threatened: Older experts did that almost as quickly as younger adults (in a fraction of a second) despite steep, age-related declines on standard tests of memory and speed (Jastrzembski et al., 2006).

When something—such as an audience, a stressor, or too much conscious thought—interferes with automatic processing, the result may be clumsy performance. This is thought to be the problem when some experienced athletes “choke under pressure”—their automatic actions are hijacked (Caro et al., 2011).

Experts have more and better strategies, especially when problems are unexpected. Indeed, strategy may be the pivotal difference between a skilled and an unskilled person. Expert chess players have general strategies for winning, and far better specific strategies for the particular responses after a move that is their specialty (Bilalic et al., 2009).

Similarly, a strategy used by expert team leaders in both the military and civilian arenas is ongoing communication, especially during slow times. Therefore, when stress builds, no team member misinterprets the previously rehearsed plans, commands, and requirements. You have witnessed the same phenomenon in expert professors: In the beginning of the semester they institute routines and policies, strategies which avoid problems later in the term.

Of course, strategies themselves need to be updated as situations change—and no chess game, or battle, or class is exactly like another. The monthly fire drill required by some schools, the standard lecture given by some professors, and the pat safety instructions read by airline attendants before takeoff become less effective over time. I recently heard a flight attendant precede his standard talk with, “For those of you who have not ridden in an automobile since 1960, this is how you buckle a seat belt.” In that pre-flight monologue I actually listened.

The superior strategies of the expert permit selective optimization with compensation. That is evident in studies of airplane pilots, a group for whom age-related declines in skill could lead to thousands of fatalities.

In one study, trained pilots were given directions by air traffic controllers in a flight simulation (Morrow et al., 2003). Experienced pilots took more accurate and complete notes and used their own shorthand to illustrate and emphasize what they heard. For instance, they had more graphic symbols (such as arrows) than did pilots who were trained to understand air traffic instructions but who had little flight experience. Thus, even though nonexperts were trained and had the tools (note paper, pencil), they did not use them the way the experts did.

In actual flights, too, older pilots take more notes than younger ones do because they have mastered this strategy, perhaps to compensate for slower working memory. Another series of studies of pilots tested repeatedly over three years confirmed that expertise fostered better strategies, as expected (Taylor et al., 2007, 2011). But unexpected was the conclusion that experience was particularly beneficial for those whose age and genes produced slower thinking.

In those longitudinal studies, some deficits in memory and reaction time began to appear as the pilots aged. But expertise meant their judgment regarding piloting a plane was still good, far better than that of pilots with less experience (Taylor et al., 2007, 2011). People show age-related losses in many studies, but experts of all ages often maintain their proficiency at their chosen occupation for years after other abilities decline. That’s selective optimization.

Finally, perhaps because they are intuitive, automatic, and strategic, experts are also more flexible in their thinking. The expert artist, musician, or scientist is creative and curious, deliberately experimenting and enjoying the challenge when things do not go according to plan (Csikszentmihalyi, 1996).

Consider the expert surgeon, who takes the most complex cases and prefers unusual patients to typical ones because operating on the unusual ones might reveal sudden, unexpected complications. Compared with the novice, the expert surgeon is not only more likely to notice telltale signs (an unexpected lesion, an oddly shaped organ, a rise or drop in a vital sign) that may signal a problem but is also more flexible and willing to deviate from standard textbook procedures if those procedures seem ineffective (Patel et al., 1999).

In the same way, experts in all walks of life adapt to individual cases and exceptions—much as an expert chef will adjust ingredients, temperature, technique, and timing as a dish develops, tasting to see if a little more spice is needed, seldom following a recipe exactly. Standards are high: Some chefs throw food in the garbage rather than serve a dish that many people would happily eat. Expert chess players, auto mechanics, and violinists are similarly aware of nuances that might escape the novice.

In the field of education, best practices for the educator now emphasize flexibility and strategy, as each group of students has distinct and often erroneous assumptions. It is not helpful to simply teach the right answers; flexibility requires matching the instruction to the individual students, discovering what learning is needed (Ford & Nove, 2011).

A review of expertise finds that flexibility includes understanding which particular skills are necessary to become an expert in each profession. For example, repeated practice is needed in typing, sports, and games; collaboration skills are needed for leadership; and task management strategies are needed for aviation (Morrow et al., 2009).

The relationship between expertise and age is not straightforward. One of the essential requirements for expertise is time.

People who become experts need months—or even years—of practice (depending on the task) to develop that expertise (Ericsson et al., 2006). Some researchers think practice must be extensive, several hours a day for at least 10 years (Charness et al., 1996; Ericsson, 1996), but that is true in only some areas. Circumstances, training, genes, ability, practice, and age all affect expertise, which means that experts in one specific field are often quite inexpert in other areas.

Expertise may counteract some effects of aging (Krampe & Charness, 2006). Much depends on the task: The young have an advantage when speed is needed, but they are less adept at vocabulary. Further, they have less experience, which may be crucial for some tasks. An interesting example comes from perfumers: They need an acute sense of smell as they seek to develop new scents. Although the sense of smell typically is reduced with age, not so for perfumers. Experts outdid younger nonexperts: they had significantly developed those parts of the brain that were attuned to smell (Delon-Martin et al., 2013).

Red Means Go! The red shows the activated brain areas in London taxi drivers as they navigated the busy London streets. Not only were these areas more active than the same areas in the average person’s brain, but they also had more dendrites. In addition, the longer a cabby had been driving, the more brain growth was evident. This research confirms plasticity, implying that we all could develop new skills, not only by remembering but also by engaging in activities that change the very structures of our brains.

FROM TALENT IN THE TAXI: A MODEL SYSTEM FOR EXPLORING EXPERTISE BY WOOLLETT ET AL, PHILOSOPHICAL TRANSACTIONS: BIOLOGICAL SCIENCE, VOL. 364, NO. 1522, MAY 2009, PP. 1407-1416, FIG. 2B.COPYRIGHT © 2009, THE ROYAL SOCIETY

This illustrates a general conclusion from research on cognitive plasticity: Experienced adults often use selective optimization with compensation, becoming expert. This is apparent in many workplaces. The best employees may be the older, more experienced ones—if they are motivated to do their best.

Complicated work requires more cognitive practice and expertise than routine work; as a result, such work may have intellectual benefits for the workers themselves. In the Seattle Longitudinal Study, the cognitive demands of the occupations of more than 500 workers were measured, including the complexities involved in the interactions with other people, with things, and with data. In all three occupational challenges, older workers maintained their intellectual prowess (Schaie, 2005).

One final example of the relationship between age and job effectiveness comes from an occupation familiar to all of us: driving a taxi. In major cities, taxi drivers must find the best route (factoring in traffic, construction, time of day, and many other details), all while knowing where new passengers are likely to be found and how to relate to customers, some of whom might want to talk, others not.

Research in England—where taxi drivers “have to learn the layout of 25,000 streets in London and the locations of thousands of places of interest, and pass stringent examinations” (Woollett et al., 2009, p. 1407)—found not only that the drivers became more expert with time, but also that their brains adjusted to the need for particular knowledge. Some regions of their brains (areas dedicated to spatial representation) were more extensive and active than those of an average person (Woollett et al., 2009). On ordinary IQ tests, the taxi drivers’ scores were average, but in navigating London, their expertise was apparent.

Other studies also show that people become more expert, and their brains adapt, as they practice various skills (Park & Reuter-Lorenz, 2009). This development occurs not only for motor skills—playing the violin, dancing, driving a taxi—but also for logic and other reasoning skills (Zatorre et al., 2012). The human brain is plastic lifelong; new learning is always possible, and practice is crucial.

This discussion of expertise has focused on occupations—surgeons, pilots, taxi drivers—that once had far more male than female workers. In recent years, two important shifts have occurred that add to this topic.

First, more women are working in occupations traditionally reserved for men. Remember from Chapter 4 that Virginia Apgar, when she earned her MD in 1933, was told she could not be a surgeon because only men were surgeons. Fortunately for the world, she became an anesthesiologist and her scale has saved millions of newborns. Today that assumption has changed; almost half the new MDs in the United States are women, and many of them have become surgeons (see Figure 21.4). More generally, most college women expect to have careers, husbands, and children, and many do so (Hoffnung & Williams, 2013).

Expect a Woman Next time you hear “The doctor will see you now,” the physician is as likely to be a woman as a man—unless the doctor is over age 40.

The second major shift is that women’s work has gained new respect. In earlier generations, women sometimes said they were “just a housewife” or “a nonworking mom.” Recently, however, the importance of work at home is increasingly recognized, and men as well as women do it. We now know that not all women are good mothers or housekeepers, and that some men are expert in domestic and emotional work that was once women’s exclusive domain. Couples who switch traditional roles are no longer rare. Most believe that for children, it is best that the father have major responsibility for child rearing (Dunn et al., 2013)

It is no longer assumed that a “maternal instinct” is innate to every mother; many mothers experience postpartum depression, financial stress, or bursts of anger and do not provide responsive child care. Certainly in some families, fathers and grandparents provide better care for children than biological mothers do. As with other adult tasks, motivation and experience are crucial for caregiving.

The skill, flexibility, and strategies needed to raise a family are a manifestation of expertise. Here again age as well as gender is important. As noted in previous chapters, in their late teens and early 20s both sexes are at their most fertile, and young women have the fewest complications of pregnancy. But conception is only a start: In general, older parents are more patient, with lower rates of child abuse as well as more successful offspring.

This is especially true if the parents have learned from experience and can listen well, as mature parents more often do. With such parents, teenagers are more likely to avoid drug addiction and other hazards. Developmentalists have not yet identified all the components necessary to become expert in child rearing, but at least we know that such expertise exists. Some parents are far more skilled than others.