290 Chapter 7 Middle Childhood 291 cultural models cognitive structures pertaining to common cultural activities body mass index (BMI) measure of the ratio of weight to height Middle childhood is the time of life when people are most likely to be slim. Section 1 Physical Development Learning Objectives 7.1 Identify the changes in physical and sensory development that tat place during middle childhood. 7.2 Explain how motor development advances in middle childhood ai how these advancements are related to new skills and participatio in games and sports. 7.3 Describe the negative effects of both malnutrition and obesity on development, and identify the causes of obesity. 7.4 Explain why rates of illness and injury are relatively low in middli childhood, and whv rates of asthma have risen. PHYSICAL DEVELOPMENT: Growth in Middle Childhood Middle childhood growth is not as rapid as at earlier ages, but children continue to add height and weight. Some children become near-sighted during these years and need to start wearing glasses. Physical Growth and Sensory Development LO 7.1 Identify the changes in physical and sensory development that take place during middle childhood. In middle childhood, physical growth continues at a slow but steady pace, about 2-3 inches (5-8 cm) per year in height and about 5-7 pounds (2M-3 kg) per year in weight. Boys continue to be slightly taller and to weigh slightly more than girls, on average. For both boys and girls, middle childhood is the time of life when they are mostly likely to be slim. Of all age groups in the life span, 6- to 10-year-olds have the lowest body mass index (BMI), a measure of the ratio of weight to height (Gillaume & Lissau, 2002). Boys continue to have somewhat more muscle than girls do in middle childhood, and girls continue to have somewhat more body fat, so the average boy is stronger than the average girl. However, both boys and girls grow stronger during this stage. For example, the average 10-year-old can throw a ball twice as far as the average Rear-old. Children run faster and longer, too, over the course of middle childhood, as lung capacity expands (Malina et al., 2004). From age 6 to 12, children lose all 20 of their "primary teeth" and new, permanent teeth replace thern. The two top front teeth are usually the first to go. The permanent ^eth arc adult-sized teeth that do not grow much once they come in, giving children in middle childhood a toothy smile that sometimes looks a little too big for their mouths. Sight and hearing both change in middle childhood, hearing usually for the better, sight more likely for the worse. Hearing often improves because the tube in the inner ear that is the site of ear infections in toddlerhood and early childhood has now matured and is longer and narrower than it was before (Bluestone, 2007). This structural change makes it less likely for fluid containing bacteria to flow from the mouth to the ear, which in turn makes inner ear infections less likely. With regard to sight, the incidence of myopia, also known as being nearsighted, rises sharply in middle childhood. This is a problem that is more likely to occur in developed countries than in developing countries. The more children read, write, and use computers, the more likely they are to develop myopia (Feldkamper & Schaeffel, 2003; Saw et al, 2002). Consequently, rates of myopia arc highest in the developed countries where children are mostly likely to have access to books and computers. Myopia is also partly genetic, as MZ twins have a higher concordance rate (see Chapter 1) than DZ twins do (Pacclla et al., 1999). About one fourth of children in developed countries need glasses by the end of middle childhood (Mutti et al., 2002). Motor Development LO 7.2 Explain how motor development advances in middle childhood and how these advancements are related to new skills and participation in games and sports. Children advance in both gross and fine motor development during middle childhood, nearly reaching maturity in their fine motor abilities. Children become stronger and more agile, and as their gross motor skills develop, they spend more of their days in active play and organized sports. They also become capable of complex fine motor activities such as writing. GROSS MOTOR DEVELOPMENT AND PHYSICAL ACTIVITY Watch a group of children on the playground of an elementary school, and you will see lots of activity. In one corner, a group of girls practices a dance routine one of them has learned from watching a TV show. In another, boys play four square, bouncing a ball into each other's square and attempting to defend their own by knocking the ball to someone else's square. In the middle, a group of boys and girls play tag, the perennial favorite. In a variety of ways, gross motor development advances from early to middle childhood. Children's balance improves, allowing them to stay steady on a bike without training wheels or walk on a board across a river. They become stronger, so that they can jump higher and throw a ball farther. Their coordination advances so that they can perform movements in activities such as swimming and skating that require the synchronization of different body parts. They have greater agility so that they can move more quickly and precisely, for example when changing directions while playing soccer. Finally, their reaction time becomes faster, allowing them to respond rapidly to changing information, for example when hitting a tennis ball over the net or when catching or hitting a baseball (Kail, 2003). Increasing myelination of the corpus callosum connecting myopia visual condition of being unable to see distant objects clearly; also known as being nearsighted 292 Chapter 7 Middle Childhood 293 the two hemispheres of the brain (see Chapter 6) accelerates reaction time in middle childhood for both gross motor and fine motor tasks (Roeder et al., 2008). The video Gross Motor Development in Middle Childhood shows examples of these advances. Watch GROSS MOTOR DEVELOPMENT IN MIDDLE CHILDHOOD A liÄwlJ*|juii!imiiii «r' ^liTit^ÄIlHIIIIJ Middle childhood is when children are most likely to be involved in organized sports. As their gross motor development advances, children can enjoy a wide range of games and sports. All over the world, middle childhood is a time of playing physically active games with siblings and friends, from tag and hide-and-seek to soccer, cricket, baseball, and basketball. Most of their play is informal, and takes place on the street or in a park or in the school yard when a few kids gather arid decide to start a game (Kirchner, 2000). However, middle childhood is also the time when children are most likely to be involved in organized sports. For example, Little League baseball is played in 75 countries around the world during the middle childhood years. In the United States, 66% of boys and 52% of girls are involved in organized sports at least once between the ages of 5 and 18 (Statistic Brain, 2014). Although boys are slightly more likely than girls to play on sports teams in middle childhood, the rate of participation among girls has risen worldwide in recent decades, especially in sports such as soccer, swimming, gymnastics, and basketball. Nevertheless, in the view of public health advocates, children do not get nearly as much gross motor activity as they should, leading to high rates of obesity, as we will see shortly. Middle childhood may be a time of great advancements in gross motor abilities, but physically active games and sports compete today with the electronic allurements of TV and computer games (Anderson & Butcher, 2006). In some places, schools are less likely than in the past to be a setting for physical activity. In the United States, the percentage of children involved in daily "physical education" programs during middle childhood decreased from 80% in 1969 to just 8% by 2005 (Centers for Disease Control and Prevention [CDC], 2006). Health authorities recommend 60 minutes of physical activity a day for children ages 6-17, but few American children get that much (see http://www.cdc.gov/physicalactivity/ everyone/guidelines/index.html). FINE MOTOR DEVELOPMENT Fine motor development also makes great advances from early childhood to middle childhood. Not many 3- or 4-year-olds can tie their shoes successfully, but nearly all 8- to 9-year-olds can. In Asian cultures, only about half of 4-year-olds can use chopsticks well enough to eat with them, but for children 6 years old and up it comes easily (Wong et al., 2002). In many developing countries, children become valuable as factory workers in middle childhood because of their abilities to perform intricate fine motor tasks such as weaving rugs (International Labor Organization [ILO], 2013). Across cultures, advances in fine motor development are especially evident in two areas, drawing and writing. In early childhood, drawing skills are limited to crude depictions of two-dimensional figures. However, in the course of middle childhood children learn to indicate three-dimensional depth by overlapping objects and making near objects smaller than distant ones (Braine et al., 1993). They also learn to draw objects in greater detail and to adjust the size and relation of objects in a drawing so that they fit together into one coherent whole (see Figure 7.1; Case & Okamoto, 1996). With regard to writing, in early childhood most children learn to write a few letters and numbers in rough form. In middle childhood, their skills greatly advance (Berninger et al., 2006). Even by age 6 most children are able to write the letters of the alphabet, their own names, and numbers from 1 to 10. In the course of the next several years, as their fine motor abilities develop, they are able to make their letters smaller and neater with more consistent height and spacing. By age 8 or 9 most children can learn to write in cursive. By the end of middle childhood their fine motor abilities have nearly reached adult maturity, whereas gross motor development will continue to advance for many years to come. Figure 7.1 Change in Drawing Abilities from Early to Middle Childhood Drawings become more realistic as fine motor development advances during middle childhood. Here are drawings that my daughter, Paris, made at ages 3 (top), 5 (left), and 7 (right). 294 Chapter 7 Practice Quiz During middle childhood _ ANSWERS AVAILABLE IN ANSWER KEY. a. girls are usually taller and heavier than boys b. girls and boys are more likely to be slim than at any other time c. the incidence of myopia decreases d. ear infections are more likely than they were earlier in the lifespan because of more exposure to germs during the school years During middle childhood,_. a. bodies are pudgier than they were in toddlerhood with a higher body mass index b. children run longer and faster because of expanded lung capacity c. the proportion of body fat is identical for girls and boys d. growth continues at the same rate as in infancy During middle childhood, there is an increase in myelination of the_that accelerates the reaction time for both boys and girls. a. Broca's area c. corpus callosum b. Wernicke's area d. pituitary gland For 6-year-old EmannueL which of the following fine motor tasks is developmental^ appropriate? a. Writing complete sentences and spelling multi-syllable words, such as "hippopotamus" b. Running a 4-minute mile, jumping over hurdles, and dribbling a basketball c. Writing the letters of the alphabet, writing his name, and writing numbers from 1 to 10 d. Writing in cursive By the time Shawna has reached the end of middle childl what abilities are close to adult maturity? a. Fine motor abilities b. Gross motor abilities c. Eye-hand coordination d. Psycho-motor skills Middle Childhood 295 J PHYSICAL DEVELOPMENT: Health Issues Middle childhood is an exceptionally healthy time of life. In this life stage, children become less vulnerable to the effects of malnutrition, and it is the time of life when they are least likely to be obese. However, obesity has become more prevalent in recent! decades in developed countries, even in middle childhood. Malnutrition and Obesity LO 7.3 Describe the negative effects of both malnutrition and obesity on development, and identify the causes of obesity. By middle childhood, children have grown large enough that they are less vulnerable to the effects of malnutrition than they were earlier. Even if they are deprived of food for a period of time, their bodies have enough resources to weather the deprivation without the effects being as severe as in earlier life stages. Nevertheless, malnutrition can have enduring negative effects in middle childhood. Obesity also becomes a problem for many children in middle childhood, especially those in developed countries. MALNUTRITION As we have seen in previous chapters, malnutrition in early devefrl opment often results in illness, disease, or death. In middle childhood, bodies are stronger and more resilient, and immune systems are better developed. Nevertheless) malnutrition has effects in middle childhood as well. Even for children who survive eariyl malnutrition, the damage to their physical and cognitive development accumulates by middle childhood (Liu et al., 2003). A longitudinal study in Guatemala showed how nutrition in the early years con tributes to cognitive and social functioning in middle childhood (Barrett & Frank, 1987). Children who were classified in early childhood as having "high nutrient levels w I more likely than children with "low nutrient levels" to explore new environments middle childhood and to persist in a frustrating situation. Thev were also more energetic, .rted their less anxious, and showed more positive emotion. A more recent study, in Ghana, repo similar results, with children who experienced mild-to-moderate malnutrition in early years demonstrating lower levels of cognitive development in middle c :hildhood onl fandardized tests and in teacher ratings, compared to chil-w'ho were not malnourished (Appoh & Krckling, 2004). he malnourished children were also more likely to be rated teachers as anxious, sad, and withdrawn (Appoh, 2004). Other studies in other countries have found similar Boys Jesuits, with better-nourished children scoring higher than malnourished children on a wide range of cognitive and social measures in middle childhood (Grigorenko, 2003; Kitsao-Wekulo et al., 2013). However, there is a consensus that the sensitive period for long-term effects of malnutrition is from the second trimester of pregnancy through age 3 (Galler et al., 2005)■ Malnutrition that begins after age 3 does not appear to result in permanent cognitive or behavioral deficits. § 15 b °- 10 Al ethnic groups African American Latino Asian American OBESITY Children in developed countries have a different kind of nutritional problem: not too few calories but too Lany. Across countries, rates of overweight and obesity are highest in the most affluent regions (North America and Europe) and lowest in the 'poorest regions (Africa and Southeast Asia) {Wang & Lobstein, 2006). Kates across the United States are higher than in most other developed countries and arc especially high in the least affluent ethnic minority groups, including African Americans and Latinos, as shown in Figure 7.2 (Ogden et al., 2014). Rates of overweight and obesity have risen sharply worldwide in recent decades. Figure 7.3 shows the increase in childhood obesity within the United States since the 1970s. 1 A variety of changes have contributed to the rise in childhood obesity (Ogden et al., 2014). Most important is the change in diets. Over recent decades people have become less likely to prepare meals at home and more likely to buy meals away from home, especially "fast foods" like hamburgers, french fries, and pizza that are high in fat content, and then they wash it down with soft drinks high in sugar content. This change reflects other social changes: Parents are less likely to prepare meals at home because they are more likely than in the past to be single parents or to be part of a dual-earner couple. Rates of overweight and obesity are rising in the populations of developing coiintries in part because their diets are becoming more like the diets of people in developed coun-fces (Gu et al, 2005; Popkin, 2010). | Another contributor is television. Most children in most developed countries watch at least 2 hours of television a day (Rideout, 2013). In a longitudinal study that followed a sample of American children from age 4 to 11, TV watching predicted gains in body m (Proctor et al., 2003). Specifically, children who watched at least 3 hours of TV a day gained 40°/» more body fat over the course of the study than children who watched less than V-h hours a day Other studies have shown that the more time children watch TV *e less time they spend in physical exercise (Institute of pfedicine, 2005; Williams, 2005). Watching TV also exposes children to numerous advertisements for high-fat, high-^gar foods, which they then lobby their parents to buy Jelly et al., 2010). Rates of overweight and obesity are especially high among African American and Latino chilli in part because those are also the children that tend *° watch the most TV per day (Rideout, 2013). The allure of fte Internet and electronic games gives children additional masons to stay inside rather than getting outside and play-active physical games (Anderson & Butcher, 2006). Genetics also make a contribution to obesity. Concor- Figure 7.2 Childhood Obesity Rates in the United States, by Ethnicity SOURCE: Based on Ogden et al. (2014). overweight in children, defined as having a BMI exceeding 18 obesity in children, defined as having a BMI exceeding 21 2001- 2005- 2009-2002 2006 2010 dam ce rates for obesity arc higher among MZ twins than Figure 7.3 The Rise in Childhood Obesity, United States, Children Ages 6-11 SOURCE: Based on Fryar et al. (2012). 296 Chapter 7 Middle Childhood 297 Rates of obesity are rising in developing countries as diets become more like those in the developed world. This photo was taken in Mexico, which has one of the highest child obesity rates in the world. DZ twins. Adopted children tend to have BMls that are closer to their biological parents than to their adopti ve parents {Whitakeret al., 1997) 1 Research has even identified a specific gene, called FTO, that sharply | increases children's risk for obesity (Frayling et al., 2007). However genetics cannot explain recent rises in obesity rates. Genetics provide only a risk for overweight and obesity, not a definite destiny. A compelling demonstration of this comes from a naturalistic study of the Pima Indians in Arizona and Mexico (Gladwell, 199g) The Pima of Mexico live in a remote region and still maintain their traditional ways, including a traditional cultural diet that is high in vegetables and low in fats and sugars. In contrast, the Pima of Arizona have changed in recent decades and their diets have become more like the American mainstream. Consequently, they have an I average BMI that is 50% higher than their counterparts in Mexico, even though the two groups are very similar genetically. Obesity has both social and physical consequences for children. Being obese increases the likelihood that a child will be socially excluded and the object of ridicule by peers (Janssen et al., 2004; Puhl et al., 2010). Other children tend to associate obesity with undesirable traits such as being lazy, sloppy, ugly, and stupid (Tiggemann & Anesbury, 2000). By middle childhood obesity is a risk factor for a variety of emotional and behavioral problems (Puhl et al., 2010). Physically, the consequences of obesity are equally serious. Even in middle childhood, obesity can result in diabetes, which can eventually lead to problems such as blindness, kidney failure, and stroke (Harmon et al., 2005; Ramchamdani, 2004). Obesity also proves hard to shake from childhood to adulthood. About 80% of obese children remain overweight as adults (Ogden et al., 2014; Oken & Lightdale, 2000), For adults, the range of health problems resulting from obesity is even greater—including high blood pressure, heart attack, and cancer—and more likely to be fatal (Ng et al., 2014). What can be done to reverse the sharp increase in childhood obesity? One step is recognizing the problem. Perhaps because obese children tend to have obese parents, studies indicate that fewer than half of parents of obese children view their children as overweight (Jeffrey, 2004; Young-Hyman et al., 2003). Public policies have begun to address the problem of childhood obesity. In the United States, school lunches have been notoriously unhealthy for decades, but national standards have been recently revised to provide healthier school lunches that are lower in fats and sugars (Jalonick, 2010). CRITICAL THINKING QUESTION Why do you think overweight and obesity are most common among low-income American ethnic groups even though, internationally, overweight and obesity are highest in the highest income countries? Illness and Injuries LO 7.4 Explain why rates of illness and injury are relatively low in middle childhood, and why rates of asthma have risen. Middle childhood is in many ways the safest, healthiest time of life. In both developed countries and developing countries, death rates are lower during middle childhood than at any other period of the life span (Hyder & Lunnen, 2009; National Center for Health Statistics [NCHS], 2009). In developed countries, by middle childhood nearly all children have been vaccinated against the diseases that may have been fatal in earlier eras, such as smallpox, typhus, and diphtheria. In developing countries, an increasing proportion of children receive vaccinations in infancy, toddlerhood, and early childhood (World Health Organization [WHO], 2010). Even children who do not receive vaccinations are less susceptible to fatal diseases in middle childhood than they were earlier in their development. Their natural immune systems have become stronger, and their bodies are bigger, stronger, and more resilient. In developed countries, even rates of minor illnesses have declined in middle childhood in recent decades, due to public health policies. Over time, food production has become cleaner and safer, and food content more closely regulated by government agencies. The air and water have become cleaner in developed countries due to laws and restrictions by governments. For example, according to national U.S. studies, in 1978 nearly 30% of children ages 5-10 had dangerously elevated levels of lead in their blood, which can cause brain damage; by 2001, the rate had fallen to 1% (Morbidity and Mortality Weekly Report [MMWR], 2005). This decline reflects government policies that eliminated lead from gasoline and household paint. One exception to this trend toward healthier development in middle childhood is asthma, a chronic illness of the lungs characterized by wheezing, coughing, and shortness of breath. A person with asthma has periodic "asthma attacks" in which breathing is especially difficult (Israel, 2005). An asthma attack can be triggered by cold weather, exercise, illnesses, allergies, emotional stress, or for no clear reason (Akinbami & Schoendorf, 2002). Asthma attacks can be reduced through the use of medical injections and inhalers (Glauber et al., 2001; Yoos et al., 2006). Rates of asthma are highest in middle childhood, and are increasing worldwide (Greenwood, 2011). Boys are at higher risk than girls, for reasons that are not clear (Federico & Tiu, 2003). Other risk factors are low birth weight, having a parent who smokes, living in poverty and obesity (Saha et al., 2005). Susceptibility to asthma is also transmitted genetically (Bosse & Hudson, 2007). Why are rates of asthma higher now than in the past? The answer appears to be different for developed countries than for developing countries. In developed countries, common features of today's family households contribute to asthma, including carpets, hairy pets, and airtight windows (Tamay et al., 2007). There is also a "hygiene hypothesis" suggesting that high standards of cleanliness and sanitation expose children to fewer viruses and bacteria, and consequently they have fewer illnesses in their early years that would strengthen their immune systems and make them less susceptible to asthma (Tedeschi & AiraghL 2006). In developing countries, air pollution has become worse as a result of increased industrialization, and air pollution can trigger asthma. One study in Mongolia compared people in rural and urban areas and found substantially higher rates of asthma in urban areas, due mainly to poorer air quality (Vinanen et al, 2007). Rates of asthma are especially high among African American children, because they often live in urban neighborhoods where the air quality is poor (Pearlman et al., 2006). African Americans also have especially high rates of risk factors for asthma such as low birth weight and obesity. However, one study found that among children with asthma, the families of African American children were more likely than White families to take steps to change the environment in order to reduce risk factors that can trigger asthma attacks, with steps including use of mattress covers, use of pillow covers, cigarette smoke avoidance, pet avoidance, and carpet removal (Roy & Wisnivesky, 2010). Like illness rates, injury rates are relatively low in middle childhood (Hyder & Lunnen, 2011; U.S. Department of Health and Human Services, 2005). Children in middle childhood are more agile than younger children and better at anticipating situations that may cause injury; compared to older children, they are kept closer to home and so are less likely to become involved in risky situations. The most common cause of injury in middle childhood is automobile accidents, followed by bicycle accidents (Safe Kids Worldwide, 2013). The use of bicycle helmets has become common in middle childhood in recent decades, and this practice has led to a sharp decrease in the number of head injuries experienced during these years (Miller et al., 2012). Middle childhood is when rates of asthma are highest. This Indian girl is using an inhaler to relieve the symptoms. asthma chronic illness of the lungs characterized by wheezing, coughing, and shortness of breath 298 Chapter 7 Middle Childhood 299 Practice Quiz ANSWERS AVAILABLE IN ANSWER KEY. 1. What is the current understanding of how genetics influence obesity? a. Genetics is a good explanation for recent rises in obesity rates during childhood; however it does little to explain the rates of obesity for adulthood. b. Genetics only explains obesity with regard to females. c. Obesity is more likely to be caused by genetics than the environment. d. Genetics cannot explain recent rises in obesity rates, but rather, genetics provides only a risk for overweight and obesity. 2. Rates of childhood obesity_' a. are higher in the United States than in most other developed countries b. are equally high in different parts of the United States c. have stayed relatively stable in the last decade d. are highest among Americans from economically advantaged backgrounds who have access to more foods 3. Your neighbors eat out quite a bit, and most of it is fast food. Their 8-year-old daughter is obese with a BMI of 24. Which of the following statements is most accurate? a. They should not be concerned because most children outgrow their obesity, b. As long as they emphasize that "beauty is from within," they should not be concerned about emotional problems. c. They should be concerned because she is at heightened risk for kidney failure and blindness. d. They should be concerned because of an increased chance of ADHD correlated with the stress of being obese. 4. In developed countries,_. a. lead poisoning continues to be one of the top causes of death during middle childhood b. middle childhood is the least safe time of life because of an increased need for independence at this period in development c. even children who do not receive vaccinations are less susceptible to fatal diseases in middle childhood than they were earlier in their development d. rates of minor illnesses have increased during recent decades, even though rates of more serious illnesses have declined 5. Which of the following is a risk factor for asthma? a. Being male b. Living in the Western part of the United States c. Having French ancestry d. Being underweight Summary: Physical Development LO 7.1 Identify the changes in physical and sensory development that take place during middle childhood. In middle childhood physical growth continues at a slow but steady pace, about 2-3 inches (5-8 cm) per year in height and about 5-7 pounds (2J/£-3 kg) per year in weight. Children lose all 20 primary teeth and their permanent teeth begin to grow in. Ear health improves, but one-fourth of children become nearsighted during middle childhood. LO 7.2 Explain how motor development advances in middle childhood and how these advancements are related to new skills and participation in games and sports. Children's gross motor skills improve in middle childhood due to improved balance, increased strength, better coordination, greater agility, and faster reaction time. As their gross motor development advances, children improve their performance in a wide range of games and sports, and many of them participate in organized sports. Fine motor development reaches nearly an adult level at this age, and across cultures, advances are especially evident in two areas: drawing and writing. LO 7,3 Describe the negative effects of both malnutrition and obesity on development, and identify the causes of obesity. Studies have shown that better-nourished children are more energetic, less anxious, show more positive emotion, and score higher than malnourished children on a wide range of cognitive measures in middle childhood. Across countries, rates of overweight and obesity are highest in the most affluent regions (North America and Europe) and lowest in tire poorest regions (Africa and Southeast Asia). Obesity is a cultural phenomenon, and a variety of social and cultural changes have contributed to this problem, including diets with more fast food and high rates of television viewing. Genetics also make a contribution. Socially, being obese increases the likelihood that a child will be excluded and the object of ridicule by peers, Physically, obesity can result in diabetes in middle childliood, which eventually can lead to problems such as blindness, kidney failure, and stroke. LO 7.4 Explain why rates of illness and injury are relatively low in middle childhood, and why rates of asthma have risen. In both developed and developing countries, middle childhood is a time of unusually high physical well-being, with low rates of illnesses and diseases due to stronger immune systems, and the health of children has improved in recent years because of increased immunization rates and better public health policies. Rates of asthma have risen in developed countries due to carpets, pets, and airtight windows, and in developing countries due to worsening air pollution. Compared to younger children, children in middle childhood are more agile and better at anticipating situations that may cause injury. Section 2 Cognitive Development Learning Objectives 17.5 Explain the major cognitive advances that occur during Piaget's concrete operations stage. 7.6 Describe how attention and memory change from early childhood to middle childhood, and identify the characteristics of children who have ADHD. 7.7 Describe the main features and critiques of intelligence tests, and compare and contrast Gardner's and Sternberg's approaches to conceptualizing intelligence. 7.8 Identify the advances in vocabulary, grammar, and pragmatics during middle childhood. 7.9 Explain the consequences for cognitive development of growing up bilingual. 7.10 Summarize the variations worldwide in school enrollment, socialization practices, and academic achievement during middle childhood. 7.11 Describe how reading and math skills develop from early childhood to middle childhood and the variations in approaches to teaching these skills. COGNITIVE DEVELOPMENT: Theories of Cognitive Development As we have seen in previous chapters, Piaget's approach and the information processing approach offer two different but complementary ways of understanding cognitive development. First we examine Piaget's ideas about concrete operations, then we discuss information processing advances in attention and memory. Concrete Operations LO 7.5 Explain the major cognitive advances that occur during Piaget's concrete operations stage. If you grew up in a Western country, perhaps you believed in Santa Claus when you were a young child. According to the story, Santa Claus rides a sleigh borne by flying reindeer around the world on Christmas Eve, and at each house he comes down the chimney and delivers toys to all the good girls and boys. Do you remember when you stopped believing it? For most children, the story starts to seem far-fetched once they get to be 7 or 8 years old (Sameroff & Haith, 1996). How could one person make it all the way around the world in one night, even with flying reindeer? How could a large man make ^ down a narrow chimney, dragging a sack full of toys? And what if you don't have a chimney? The loss of belief in this myth reflects gains in cognitive development, as children develop a more true-to-life understanding of the world. 300 Chapter 7 Middle Childhood 301 concrete operations in Piaget's theory, the cognitive stage in which children become capable of using mental operations seriation ability to arrange things in a logical order, such as shortest to longest, thinnest to thickest, or lightest to darkest Middle childhood is when children develop a better grasp of what the physical world is really like and what is and is not possible. Recall from Chapter 6 that according I to Piaget's theory of cognitive development, early childhood is the preoperational stage in Piaget's view, children ages 2-6 are most notable cognitively for what they cannot do— they cannot perform mental operations—and for the kinds of mistakes they make. Around age 7, children make an important cognitive advance toward becoming more systematic, planful, and logical thinkers. Piaget termed the cognitive stage from age 7 to 11 concrete operations. During this stage children become capable of using mental operations, which allow them to organize and manipulate information mentally instead of relying on physical and sensory associations. According to Piaget, the advances of concrete operations are evident in new abilities for performing tasks of conservation classification, and seriation. ADVANCES IN CONCRETE OPERATIONS As described in Chapter 6, prior to age 7 children usually make mistakes when performing tasks requiring an understanding of conservation (refer back to Learning Objective 6.6). Conservation is a key milestone of cognitive development because it enables the child to perceive regularities and principles in the natural world, which is the basis of being able to think logically about how the world works. A second important cognitive achievement of concrete operations is classification. Although in early childhood young children can sort objects or events that share common characteristics into the same class—red, round, sweet, dog, for example—and can also combine classes into more general categories—elephants and rabbits are both part of the larger class "animals"—they run into difficulty when a classification problem requires a mental operation. For example, in one experiment, Piaget showed a 5-year-old boy a drawing of 12 girls and 2 boys, and this exchange followed (Piaget, 1965, p. 167): Piaget: Are there more girls or more children? Boy: More girls. Piaget: But aren't the girls children? Boy: Yes. Piaget: Then are there more children or more girls? Boy: More girls. Amusing, no doubt, at your age, but if you think about it, answering this question requires a fairly challenging mental operation, at least for a 5-year-old. He must separate the girls and boys in the drawing into two classes (girls and boys), add them to form a larger class (children), and understand that the larger class (children) can be broken down again into each of its subclasses (girls and boys). Crucially, this must be done mentally. The number of girls can be compared to the number of boys visually, but comparing the number of children to the number of girls cannot, because girls are part of both categories. For this reason the 5-year-old trips up on the problem, but by age 8 or 9 most children perform this mental operation easily. In another experiment, Piaget interviewed a 9-year-old boy, showing him a drawing of 12 yellow tulips, 3 red tulips, and 6 daisies: Piaget: Which would make a bigger bunch, all the tulips or the yellow tulips? Boy: All the tulips, of course. You'd be taking the yellow tulips as well. Piaget: And which would be bigger, all the tulips or all the flowers? Boy: All the flowers. If you take all the flowers, you take all the tulips, too. (Adapted from Gfnstmrg & Opper, 1979, p. 123) Seriation, the third achievement of concrete operations emphasized by Piaget, is the ability to arrange things in a logical order (e.g., shortest to longest, thinnest to thickest, lightest to darkest). Piaget found that preoperational children have an incomplete grasp of concepts such as longer than or smaller than. For example, when asked to arrange a set of sticks from shortest to longest, children in the preoperational age period would typically start with a short stick, then pick a long stick—but then pick another short stick, then another long stick, and so on. However, by age 7 most children can accurately arrange six to eight sticks by length. The video Seriation provides more examples of this. Watch SERIATION This kind of seriation task can be done visually—that is, it does not require a mental operation—but Piaget also found that during concrete operations children developed the ability to seriate mentally. Take this problem, for example. If Julia is taller than Anna and Anna is taller than Lynn, is Julia taller than Lynn? To get this right, the child has to be able to order the heights mentally from tallest to shortest: Julia, Anna, Lynn. Piaget considered the achievement of this skill of performing mental operations to be a key part of learning to think logically and systematically. EVALUATING PIAGET'S THEORY As mentioned in Chapter 6, research testing Piaget's theory has found that, for concrete operations as for the preoperational stage, children are capable of performing some tasks at an earlier age than Piaget had claimed (Marti & Rodriguez, 2012; Vilette, 2002). However, for Piaget it was not enough for a child to grasp some aspects of conservation, classification, and seriation in order to be considered a concrete operational thinker; the child had to have complete mastery of the tasks associated with the stage (Piaget, 1965). Thus, the difference between Piaget and his critics on this issue is more a matter of definition—"What qualifies a child as a concrete operational thinker?"—than of research findings. Piaget also claimed that teaching children the principles of concrete operations would not work because their grasp of the principles of the stage has to occur naturally as part of their interaction with their environment (Piaget, 1965). Here his critics appear to be right, with many studies showing that with training and instruction, children under age 7 can learn to perform the tasks of concrete operations and also understand the underlying principles well enough to apply them to new tasks (Marti & Rodriguez, 2012; Parameswaran, 2003). Transporting Piaget's tasks across cultures shows that acquiring an understanding of concrete operations depends on exposure to similar tasks and materials. For example, in one study of 4- to 13-year-old children in the Maya culture of Mexico and in Los Angeles, the children in Los Angeles performed better than the Mayan children on standard tests of concrete operations, whereas the Mayan children performed better on similar concrete operations tasks that involved materials used in weaving, because these materials were familiar from their daily lives (Maynard & Greenfield, 2003). 302 Chapter 7 Middle Childhood 303 selective attention ability to focus attention on relevant information and disregard what is irrelevant attention-deficit/ hyperactivity disorder (ADHD) diagnosis that includes problems of inattention, hyperactivity, and impulsiveness Information Processing LO 7.6 Describe how attention and memory change from early childhood to middle childhood, and identify the characteristics of children who have ADHD. Ever try to play a board game with a 3-year-old? If you do, it better be short and siml pie. But by middle childhood, children can play a wide variety of board games that adults enjoy, too, because their powers of attention and memory have advanced. This-1 is one reflection of how information processing improves during middle childhood. Due to increased myelination in the brain, especially of the corpus callosum connecting the two hemispheres, speed of processing information increases (Roeder et al., 2008) Consequently, the amount of time required to perform various tasks decreases in the course of middle childhood. Advances are also made in the two key areas of mformatic-n processing: attention and memory, ATTENTION AND ADHD In middle childhood, children become more capable of focusing their attention on relevant information and disregarding what is irrelevant, an ability termed selective attention (Goldberg et al., 2001; janssen et al., 2014). For example, in one line of research, children of various ages were shown a series of cards, each containing one animal and one household item, and told to try and remember where the animal on each card was located (Hagen & Hale, 1973). Nothing was mentioned about the household items. Afterward, when asked about the location of the animals on each card, older children performed better than younger children.. However, when asked how many of the household items they could remember, younger children performed better than older children. The older children were capable of focusing on the information they were told would be relevant, the location of the animals, and capable of ignoring the household items as irrelevant. In contrast, the poorer performance of the younger children in identifying the locations of the animals was partly due to being distracted by the household items. Being able to maintain attention becomes especially important once children enter school at about age 6 or 7, because the school setting requires children to pay attention to their teachers' instructions. Children with especially notable difficulties in maintaining attention may be diagnosed with attention-deficit/hyperactivity disorder (ADHD), which includes problems of inattention, hyperactivity, and impulsiveness. Children with ADHD have difficulty following instructions and waiting their turn, In the United States, it is estimated that 7% of children ages 4-10 are diagnosed with ADHD (National Resource Center on ADHD, 2014). Boys arc over twice as likely as girls to have ADHD. The diagnosis is usually made by a pediatrician after evaluation of the child and consultation with parents and teachers (Sax & Kautz, 2003). Watch the video A Boy Talks About Having ADHD for a child's perspective on the disorder. In the United States, nearly 9 of 10 children and adolescents diagnosed with ADHD receive Ritalin or other medications to suppress their hyperactivity and help them concentrate better (Kaplan et al., 2004). Medications are often effective in controlling the symptoms of ADHD, with 70% of children showing improvements in academic performance and peer relations (Prasad et al. 2013). However, there are concerns about side effects, including slower physical growth and higher risk of depression (Reeves & Schweitzer, 2004). Behavioral therapies are also effective, and the combination of medication and behavioral therapy is more effective than either treatment alone (American Academy of Pediatrics, 2005; Hoza et al., 2008). Although most research on ADHD has taken place in the United States, one large study of ADHD was completed in Europe, involving over 1,500 children and adolescents (ages 6-18) in 10 countries (Rotheberger et al., 2006). In this Attention-deficit/hyperactiv-ity Disorder Observational Research in Europe (ADORE) study, pediatricians and child psychiatrists across Europe collected observational data on children and adolescents at WatCh A BOY TALKS ABOUT HAVING seven time points over 2 years, with data including diagnosis, treatment, and outcomes. Parents also participated, and their assessments showed high agreement with the assessments of the pediatricians and child psychiatrists. Like the American studies, ADORE found higher rates of ADHD among boys than among girls, but the ratios varied widely among countries, from 3:1 to 16:1 (Novik et al., 2006). Symptoms of ADHD were similar among boys and girls, but girls with ADHD were more likely than boys to have additional emotional problems and to be bullied by their peers, whereas ADHD boys were more likely than girls to have conduct problems. For both boys and girls, having ADHD resulted in frequent problems in their relations with peers, teachers, and parents (Coghill et al., 2006). Parents reported frequent stresses and strains due to children's ADHD behavior, including disruptions of family activities and worries about the future (Riley et al., 2006). In contrast to the American approach of relying heavily on Ritalin and other medications, the European approaches to treatment were diverse: medications (25%), psychotherapy (19%), combination of medications and psychotherapy (25%), other therapy (10%), and no treatment (21%) (Preuss et al., 2006). MEMORY In early childhood, memory is often fleeting, as any parent can attest who has ever asked a 4-year-old what happened to those nice new mittens he wore out to play that morning. Mittens? What mittens? In middle childhood the capacity of working memory enlarges. On memory tests for sequences of numbers, the length of the sequence recalled is just 4 numbers for the typical 7-year~old, but for the typical 12-year-old it has increased to 7, equal to adults (Kail, 2003). More importantly, middle childhood is the period when children first learn to use mnemonics (memory strategies) such as rehearsal, organization, and elaboration. Rehearsal, which involves repeating the information over and over, is a simple but effective mnemonic. You probably use it yourself, for example, when someone tells you a phone number and you are trying to remember it between the time you hear it and the hrne you use it. In a classic study, John Flavell and his mnemonics memory strategies, such as rehearsal, organization, and elaboration rehearsal mnemonic that involves repeating the same information over and over ADHD is usually first diagnosed in middle childhood, when children arc required to sit still for long pen ■iods in school. 304 Chapter 7 Middle Childhood 305 organization mnemonic that involves placing things mentally into meaningful categories elaboration mnemonic that involves transforming bits of information in a way that connects them and hence makes them easier to remember metamemory understanding of how memory Why do young chess masters remember chess configurations better than older novices do? colleagues (1966) showed how rehearsal emerges as a memory strategy in middle hifl hood. They outfitted children ages 5 and 10 with a space helmet with a dark visor A displayed seven pictures of familiar objects in front of them. Each child was told thatrtf researcher was going to point to three objects that the child was to remember (in 0rde I then pull down the space helmet visor so the child could not see for 15 seconds and th ' I lift the visor and ask the child to point to the three objects. During the 15-second dela nearly all of the 10-year-olds but only a few of the 5-year-olds moved their lips or recited the names of the objects aloud, showing that they were using rehearsal. At each a rehearsers recalled the objects much more accurately than non-rehearsers. Organization—placing things into meaningful categories—is another effective mem.l ory strategy that is used more commonly in the course of middle childhood (Schneider 2002). Studies typically test this ability by giving people a list of items to remember for example, shoes, zebra, baseball, cow, tennis racket, dress, raccoon, soccer goal, hat Numerous studies have shown that if children are given a list of items to remember, they J are more likely to group them into categories—clothes, animals, sports items—in middle childhood than in early childhood (Sang et al., 2002). Organization is a highly effective memory strategy, because each category serves as a retrieval cue for the items within the category, so that if the category can be remembered, all the items within the category are likely to be remembered as well (Schneider, 2002). A third mnemonic that comes into greater use in middle childhood is elaboration which involves transforming bits of information in a way that connects them and hence makes them easier to remember (Terry, 2003). One example of this is the standard way om teaching children the lines of the treble clef in music, EGBDF: Every Good Boy Does Fine. I Or, if you were going to the grocery store and wanted to remember to buy butter, lettuce, I apples, and milk, you could arrange the first letters of each of the items into one word, 1 BLAM. The word BLAM serves as a retrieval cue for the items represented by each letter of the word. Although children are more likely to use organization and elaboration in middle childhood than in early childhood, even in middle childhood and beyond, relatively few I people use memory strategies on a regular basis. Instead, they rely on more concrete, I practical methods. In one study, children in kindergarten and 1st, 3rd, and 5th grade were asked how they would remember to bring their ice skates to a party the next day (Kreutzer et al., 1975). At all three ages, children came up with sensible approaches such as putting the skates where they would be easy to see, writing themselves a note, and 1 tying a string to their finger. Another reason why memory improves from early childhood to middle childhood is that children's knowledge base expands, and the more you know, the easier it is tol remember new information that is related to what you know. In a classic study illustrating this, 10-year-old chess masters and college student novice chess players were compared in their ability to remember configurations of pieces on a chess board (Chi, 1978). The 10-year-old chess masters performed far better than the college student novices, even though the college students were better at recalling a series of random numbers. In another study, 9- and 10-year-olds were separated into two groups, soccer "experts" and soccer "novices," and asked to try to remember lists of soccer items and non-soccer items (Schneider & Bjorklund, 1992). The soccer experts remembered more items on the soccer list than on the non-soccer list. Middle childhood is not only a time of advances in memory abilities but of advances in understanding how memory works, or metamemory. Even by age 5 or 6, most children have some grasp of metamemory (Kvavilashvili & Ford, 2014). They recognize that it is easier to remember something that happened yesterday than something that happened long ago. They understand [ short lists are easier to remember than long lists, and that fajniliar items are more ^jlv remembered than unfamiliar items. However, their appraisal of their own memory Lhilities tends to be inflated. When children in early childhood and middle childhood 8 shown a series of 10 pictures and asked if they could remember all of them, more than half of the younger children but only a few older children claimed they could (none of them actually could!) (Flavell et al., 1970). In the course of middle childhood, children develop more accurate assessments of their memory abilities (Schneider & Pressley,1997). IIntelligence and Intelligence Tests f iO 7-7 Describe the main features and critiques of intelligence tests, and compare and contrast Gardner's and Sternberg's approaches to conceptualizing intelligence. Both the Piagetian approach and the information-processing approach describe general patterns of cognitive development and functioning, intended to apply to all children. However, at any given age there are also individual differences among children in their cognitive functioning. Within any group of same-age children, some will perform relatively high in their cognitive functioning and some relatively low. Even in infancy, toddlerhood, and early childhood, individual differences in cognitive development are evident, as children reach various cognitive milestones at different times, such as saying their first word. However, individual differences become more evident and more important in middle childhood, when children enter formal schooling and begin to be tested and evaluated on a regular basis. In the study of human development, the examination of individual differences in cognitive development has focused mainly on measurements of intelligence. Definitions of intelligence vary, but it is generally understood to be a person's capacity for acquiring knowledge, reasoning, and solving problems (Sternberg, 2004). Intelligence tests usually provide an overall score of general intelligence as well as several subscores that reflect different aspects of intelligence. Let us begin by looking at the characteristics of one of the most widely used intelligence tests, and follow with an exploration of the genetic and environmental sources of individual differences in intelligence. Then, we will consider two alternative ways of conceptualizing and measuring intelligence. THE WECHSLER INTELLIGENCE TESTS The most widely used intelligence tests are the Wechsler scales, including the Wechsler Intelligence Scale for Children (WISC-IV) for ages 6 to 16 and the Wechsler Adult Intelligence Scale (WAIS-IV) for ages 16 and up. The Wechsler scales consist of 11 subtests, of which 6 are Verbal subtests and 5 are Performance subtests. The results provide an overall intelligence quotient, or IQ score, which is calculated relative to the performance of other people of the same age, with 100 as the median score. The overall IQ can be broken down into a Verbal IQ score, a Performance IQ score, and scores for each of the 11 subtests. More detail on each of the subscales of the WISC-IV is provided in Table 7.1 on the next page, so you can get an idea of what IQ tests really measure. How accurate are the Wechsler IQ tests? IQ tests were originally developed to test children's abilities as they entered school, and IQ has proven to be a good predictor of children's school performance. One study of children in 46 countries found that across countries, IQ scores and school achievement scores were highly correlated (Lynn & Mikk, 2007). IQ scores are also quite good predictors of success in adulthood, as Chapter 10 will explore in more detail (Benbow & Lubinski, 2009). However, IQ tests have been criticized on a variety of grounds. Critics have complained that IQ tests assess only a narrow range of abilities, and miss some of the most intelligence capacity for acquiring knowledge, reasoning, and solving problems intelligence quotient (IQ) score of mental ability as assessed by intelligence tests, calculated relative to the performance of other people the same age median in a distribution of data, the score that is precisely in the middle, with half the distribution lying above and half below 306 Chapter 7 Middle Childhood 307 Table 7.1 The WISC-IV: Sample Items normal distribution typical distribution of characteristics of a population, resembling a bell curve in which most cases fall near the middle and the proportions decrease at the low and high extremes intellectual disability level of cognitive abilities of persons who score 70 or below on IQ. tests gifted in IQ test performance, persons who score 130 or above Verbal Subtests Information Vocabulary Similarities Arithmetic Corr prehünsion Digit Span Performance Sub Picture arrangement Picture completion Matrix reasoning Block design Digit symbol General knowledge questions, for example, "Who wrote Huckleberry Finn?" Give definitions, lor example, "What does formulate mean?" Describe relationship between two things, for example, "In what ways are an apple and an orange alike?" and "In what ways are a book and a movie alike?" Verbal arithmetic problems, tor example. "How many hours does it take to drive 140 1 miles at a rate of 30 miles per hour?" Practical knowledge, for example, "Why is it important to use zip codes when you mail letters?" Short term memory lest. Sequences of numbers of increasing length are recited, and trwM person is required to repeat them. For all the performance tests, scores are based on speed as well as accuracy of response. Cards depicting vanous activities are provided, and the person is required to place them ■ m an order that tells a coherent story. Cards are provided depicting an object or scene with something missing, and the person I is required to point out what is missing (for example, a dog is shown with only three legs), Patterns are shown with one piece missing. The person chooses from five options the f one that will fili in the missing piece accurately. Blocks are provided with two sides all white, two sides all red, and two sides half red and I half white. A card is shown with a geometrical pattern, and the person must arrange the ■ blocks so that they match the pattern on the card. At top of sheet, numbers are shown with matching symbols. Below, sequences uf sym- 'I bols are given with an empty box below each symbol. The person must place the match- 1 ing number in the box below each symbol. important aspects of intelligence, such as creativity. IQ tests have also been attacked as culturally biased, because some of the vocabulary and general knowledge items would be more familiar to someone who was part of the middle-class culture (Ogbu, 2002). However, attempts to develop "culture-fair" tests have found the same kinds of group differences as standard IQ tests have found (Johnson et al., 2008). It may not be possible to develop a culture-fair or culture-free IQ test, because by the time people are able to take the tests (age 6) their cognitive development has already been shaped by living in a particular cultural and social environment. Although IQ tests aspire to test raw intellectual abilities, this would not really be possible unless everyone was exposed to essentially the same environment in the years before taking the test, which is obviously not the case. However, new approaches to studying intelligence have provided important insights into the relation between genetics and environment in performance on IQ tests, as we will discuss next. INFLUENCES ON INTELLIGENCE IQ scores for a population-based sample usually fall into a normal distribution, or bell curve, in which most people are near the middle of the distribution and the proportions decrease at the low and high extremes, as shown in Figure 7.4. Persons with IQs below 70 are classified as having intellectual disability, and those with IQs above 130 are classified as gifted. But what determines whether a person's score is low, high, or somewhere in the middle? Is intelligence mainly an inherited trait, or is it shaped mainly by the environment? As noted in Chapter 2, social scientists increasingly regard the old nature-nurture debates as sterile and obsolete. Nearly all accept that both genetics and environment are involved in development, including in the development of intelligence. A variety of new findings presented in the past 20 years provide insights into how genetics and environments interact and how both contribute to intelligence. Most of these studies use the Figure 7.4 Bell Curve for Intelligence IQ scores for a population-based sample usually fall into this kind of pattern. natural experiments of adoption studies or twin studies in order to avoid the problem of passive genotype —> environment effects. When parents provide both generics and environment, as they do in most families, it is very difficult to judge the relative contribution of each. Adoption and twin studies help unravel that tangle. One important conclusion from adoption and twin studies is that the more two people in a family are alike genetically, the higher the correlation in their IQs (Brant et al., 2009). As shown in Figure 7.5, adopted siblings, who have none of their genotype in common, have a relatively low correlation for IQ, about .24. The environmental influence is apparent—ordinarily, the correlation between two genetically unrelated children would be zero—but limited. Parents and their biological children, who share half of their genotype in common, are correlated for IQ at about .40, slightly higher if they live together than if they live apart. The correlation for biological siblings is higher, about .50, and slightly higher still for DZ twins. Biological siblings and DZ twins share the same proportion of their genotype in common as parents and biological children do (again, about half), so the greater IQ similarity in DZ twins must be due to greater environmental similarity, from the womb onward. The highest IQ correlation of all, about .85, is among MZ twins, who have exactly the same genotype. Even when they are adopted by separate families and raised apart, the correlation in IQ scores of MZ twins is about .75 (Brant et al., 2009). The results of these studies leave little doubt that genetics contribute strongly to IQ scores. It is especially striking that the correlation in IQ is much lower for adopted siblings, who have grown up in the same family and neighborhood and attended the same schools, than it is for MZ twins who have been raised separately and have never even known each other. However, other adoption studies show that both environment and genetics have a strong influence on intelligence. In one study, researchers recruited a sample of adopted children whose biological mothers were at two extremes, either IQ under 95 or above 120 (remember, 100 is the median population IQ) (Loehlin et al., 1997). All the Figure 7.5 IQ and Genetics The closer the genetic relationship, the higher the correlation in I source: Based on Brant et al. (2009). 308 Chapter 7 Childhood 309 Identical twins have similar TQs, even when reared apart. Here, 6-year-old MZ twin sisters in Thailand smile for the camera. Flynn effect steep rise in the median IQ score in Western countries during the 20th century, named after James Flynn, who first identified it 100 I 95 I 90 85 75 hildren had been adopted at birth by parents who were ab^B average in education and income. When tested in middle child, hood, children in both groups were above average in IQ If w can assume that the high-education, high-income adopts parents provided a healthy, stable, stimulating environment this shows a strong influence of the environment for the chit dren whose biological mothers all had IQs less than 95.