Preschool Parent Handout week 4

CHAPTER 8 PHYSICAL DEVELOPMENT IN EARLY CHILDHOOD

My Back Yard

Andy Laing, 6 years, USA

This artist depicts early childhood just as it is often described: “the play years.” Chapter 8 highlights the close connections between physical growth and other aspects of young children’s development.

Reprinted with permission from Children’s Museum of the Arts Permanent Collection, New York, NY

WHAT’S AHEAD IN CHAPTER 8

8.1 A Changing Body and Brain

Skeletal Growth • Brain Development

8.2 Influences on Physical Growth and Health

Heredity and Hormones • Sleep Habits and Problems • Nutrition • Infectious Disease • Childhood Injuries

■ Biology and Environment: Childhood Poverty and Brain Development

■ Social Issues: Health: Otitis Media and Development

8.3 Motor Development

Gross-Motor Development • Fine-Motor Development • Individual Differences in Motor Skills • Enhancing Early Childhood Motor Development

■ Cultural Influences: Why Are Children from Asian Cultures Advanced in Drawing Skills?

For more than a decade, my fourth-floor office windows overlooked the preschool and kindergarten play yard of our university laboratory school. On mild fall and spring mornings, classroom doors swung open, and sand table, easels, and large blocks spilled out into a small courtyard. Alongside the building was a grassy area with jungle gyms, swings, a playhouse, and a flower garden planted by the children; beyond the garden, a circular path lined with tricycles and wagons could be seen. Each day, the setting was alive with activity.

Even from my distant vantage point, the physical changes of early childhood were evident. Children’s bodies were longer and leaner than they had been a year or two earlier. The awkward gait of toddlerhood had disappeared in favor of more refined movements that included running, climbing, jumping, galloping, and skipping. Children scaled the jungle gym, raced across the lawn, turned somersaults, and vigorously pedaled tricycles. Just as impressive as these gross-motor achievements were gains in fine-motor skills. At the sand table, children built hills, valleys, caves, and roads and prepared trays of pretend cookies and cupcakes. And as they grew older, their paintings at outdoor easels took on greater structure and detail, with family members, houses, trees, birds, sky, monsters, and letterlike forms appearing in the colorful creations.

The years from 2 to 6 are often called “the play years”—aptly so, because play blossoms during this time, becoming increasingly complex, flexible, and symbolic. Our discussion of early childhood opens with the physical attainments of this period—body and brain growth, improvements in motor coordination, and refinements in perception. We pay special attention to genetic and environmental factors that support these changes and to their intimate connection with other domains of development. The children I came to know well, first by watching from my office window and later by observing at close range in their classrooms, provide many of the examples of developmental trends and individual differences used in this chapter. ■

8.1 A CHANGING BODY AND BRAIN

8.1 Describe body growth and brain development in early childhood.

In early childhood, the rapid increase in body size of the first two years tapers off into a slower growth pattern. On average, children add 2 to 3 inches in height and about 5 pounds in weight each year. Boys continue to be slightly larger than girls. As the “baby fat” that began to decline in toddlerhood drops off further, children gradually become thinner, although girls retain somewhat more body fat than boys, who are slightly more muscular (Fomon & Nelson, 2002). As the torso lengthens and widens, internal organs tuck neatly inside, and the spine straightens. As Figure 8.1 on page 282 shows, by age 5 the top-heavy, bowlegged, potbellied toddler has become a more streamlined, flat-tummied, longer-legged child with body proportions similar to those of an adult. Consequently, posture and balance improve—changes that foster gains in motor coordination.

Individual differences in body size become more apparent in early childhood. Speeding around the bike path in the play yard, 5-year-old Darryl—at 48 inches tall and 55 pounds—towered over his kindergarten classmates. (The average North American 5-year-old boy is 43 inches tall and weighs 42 pounds.) Priti, an Asian-Indian child, was unusually small because of genetic factors linked to her cultural ancestry. And Hal, a European-American child from a poverty-stricken home, was well below average for reasons we will discuss shortly.

The existence of these variations in body size reminds us that growth norms for one population are not good standards for children elsewhere in the world. Consider the Efe of the Republic of Congo, whose typical adult height is less than 5 feet. For genetic reasons, the impact of hormones controlling body size is reduced in Efe children (Le Bouc, 2017). By age 5, the average Efe child is shorter than more than 97 percent of North American and European agemates, and Efe children reach puberty and stop growing at an earlier age than U.S. comparison children. Researchers disagree on why the Efe’s small size evolved. Some suggest that it reduces their caloric requirements in the face of food scarcity in the rain forests of Central Africa, others that it permits easy movement through the dense forest underbrush, and still others that it enables earlier childbearing to compensate for the Efe’s extremely high mortality rate (Verdu, 2016). Efe children’s short stature is not a sign of growth or health problems. But for other children, such as Hal, extremely slow growth is cause for concern.

Figure 8.1 Body growth during early childhood. During the preschool years, children grow more slowly than in infancy and toddlerhood. Wilson and Mariel’s bodies became more streamlined, flat-tummied, and longer-legged. Boys continue to be slightly taller, heavier, and more muscular than girls. But generally, the two sexes are similar in body proportions and physical capacities.

PHOTOS OF WILSON: DIAHANNE LUCAS; PHOTOS OF MARIEL: © Jim West/jimwestphoto.com

8.1.1 Skeletal Growth

The skeletal changes of infancy continue throughout early childhood. Between ages 2 and 6, approximately 45 new epiphyses, or growth centers in which cartilage hardens into bone, emerge in various parts of the skeleton. Other epiphyses will appear in middle childhood. X-rays of these growth centers enable doctors to estimate children’s skeletal age, or progress toward physical maturity (see page 155 in Chapter 5)—information helpful in diagnosing growth disorders.

By the end of the preschool years, children start to lose their primary, or “baby,” teeth. The age at which they do so is heavily influenced by genetic factors. For example, girls, who are ahead of boys in physical development, lose their primary teeth sooner. Cultural ancestry also makes a difference. North American children typically get their first secondary (permanent) tooth at 6½ years, children in Ghana at just over 5 years, and children in Hong Kong around the sixth birthday (Burns, 2000). But nutritional factors also influence dental development. Prolonged malnutrition delays the appearance of permanent teeth, whereas overweight and obesity accelerate it (Costacurta et al., 2012; Heinrich-Weltzien et al., 2013).

Like Efe children, these children of the Batwa people of Central Africa’s Great Lakes region are genetically short-statured, expected to reach a typical adult height of less than 5 feet. They remind us that growth norms for one population are not good standards for children elsewhere in the world.

© MARIAN GALOVIC/ALAMY Stock Photo

Diseased baby teeth can affect the health of permanent teeth, so preventing decay in primary teeth is essential—by brushing consistently, avoiding sugary foods, drinking fluoridated water, and getting topical fluoride treatments and sealants (plastic coatings that protect tooth surfaces). Another factor is exposure to tobacco smoke, which suppresses children’s immune systems, including the ability to fight bacteria responsible for tooth decay. The risk associated with this suppression is greatest in infancy and early childhood, when the immune system is not yet fully mature. Young children in homes with regular smokers are at increased risk for decayed teeth (Hanioka et al., 2011; Wen et al., 2017).

An estimated 23 percent of U.S. preschoolers have tooth decay, a figure that rises to 50 percent in middle childhood and 60 percent by age 18. Causes include poor diet and inadequate health care—factors that are more likely to affect children from low-SES homes. One-fourth of U.S. children living in poverty have untreated dental cavities (U.S. Department of Health and Human Services, 2018b).

8.1.2 Brain Development

Between ages 2 and 6, the brain increases from 70 percent of its adult weight to 90 percent. At the same time, preschoolers improve in a wide variety of skills—physical coordination, perception, attention, memory, language, logical thinking, and imagination. In addition to increasing in volume, the cerebral cortex undergoes much reshaping and refining.

Development of the Cerebral Cortex

By age 4 to 5, many parts of the cerebral cortex have overproduced synapses. In some regions, such as the prefrontal cortex, the number of synapses is nearly double the adult value. Together, synaptic growth and myelination of neural fibers result in a high energy need. In fact, brain-imaging evidence reveals that energy metabolism in the cerebral cortex reaches a peak around this age (Jabès & Nelson, 2014; Jiang & Nardelli, 2016).

Recall from Chapter 5 that overabundance of synaptic connections supports plasticity of the young brain, helping to ensure that the child will acquire certain abilities even if some areas are damaged. Synaptic pruning follows: Neurons that are seldom stimulated lose their connective fibers, and the number of synapses gradually declines (see page 156 in Chapter 5). As the structures of stimulated neurons become more elaborate and require more space, surrounding neurons die, and brain plasticity declines. Between ages 8 and 10, energy consumption of most cortical regions diminishes to near-adult levels (Lebel & Beaulieu, 2011). In addition, cognitive functions are no longer as widely distributed in the cerebral cortex. Rather, they increasingly localize in distinct neural systems that become better integrated, reflecting a developmental shift toward a more lateralized, fine-tuned, and efficient neural organization (Bathelt et al., 2013; Markant & Thomas, 2013).

Learning to program their own interactive stories and games challenges these 5-year-olds’ capacity to remember, think flexibly, and plan—aspects of executive function supported by rapid growth of the prefrontal cortex from early to middle childhood.

ScratchJr is a collaboration between the DevTech Research Group at Tufts University, the Lifelong Kindergarten Group at the MIT Media Lab, and the Playful Invention Company. See http://scratchjr.org

Measures of neural activity—electroencephalography (EEG), near infrared spectroscopy (NIRS), and functional magnetic resonance imaging (fMRI)—reveal especially rapid growth from early to middle childhood in prefrontal-cortical areas devoted to various aspects of executive function. These include inhibition of impulses and irrelevant behaviors, working memory, flexibility of thinking, and planning—capacities that advance markedly during the preschool years (Müller & Kerns, 2015). Furthermore, for most children, the left cerebral hemisphere is especially active between 3 and 6 years and then levels off. In contrast, activity in the right hemisphere increases steadily throughout early and middle childhood, with a slight spurt between ages 8 and 10 (Thatcher, Walker, & Giudice, 1987; Thompson et al., 2000).

These findings fit nicely with what we know about several aspects of cognitive development. Early childhood is a time of marked gains on tasks that depend on the prefrontal cortex—ones that require improved attentional control and thoughtful reflection (Rothbart, 2011). Further, language skills (typically housed in the left hemisphere) increase at an astonishing pace in early childhood, and they support children’s increasing control over behavior, also mediated by the prefrontal cortex. In contrast, spatial skills (usually located in the right hemisphere), such as giving directions, drawing pictures, and recognizing geometric shapes, develop gradually over childhood and adolescence.

Advances in Other Brain Structures

Besides the cerebral cortex, several other areas of the brain make strides during early childhood (see Figure 8.2). All of these changes involve establishing links between parts of the brain, increasing the coordinated functioning of the central nervous system.

At the rear and base of the brain is the cerebellum, a structure that aids in balance and control of body movement. Fibers linking the cerebellum to the cerebral cortex grow and myelinate from birth through the preschool years, contributing to dramatic gains in motor coordination: By the end of the preschool years, children can play hopscotch, throw a ball with well-coordinated movements, and print letters of the alphabet. Cerebellar–cortical neural circuits also support thinking. And because damage to the cerebellum in infancy is associated with impaired growth of the cerebral cortex, they appear to be crucial for typical brain development (Stoodley, 2016). Children with injury to the cerebellum usually display both motor and cognitive deficits, including problems with memory, planning, and language (Hoang et al., 2014; Noterdaeme et al., 2002).

Figure 8.2 Cross-section of the human brain, showing the location of the cerebellum, the reticular formation, the hippocampus, the amygdala, and the corpus callosum. These structures undergo considerable development during early childhood. Also shown is the pituitary gland, which secretes hormones that control body growth (see page 286).

The reticular formation, a structure in the brain stem that maintains alertness and consciousness, generates synapses and myelinates throughout early childhood and into adolescence (Sampaio & Truwit, 2001). Neurons in the reticular formation send out fibers to other areas of the brain. Many go to the prefrontal cortex, contributing to improvements in sustained, controlled attention.

An inner brain structure called the hippocampus, which plays a vital role in memory and in images of space that help us find our way, undergoes rapid synapse formation and myelination in the second half of the first year, when recall memory and independent movement emerge. Over the preschool and elementary school years and into early adolescence, the hippocampus and surrounding areas of the cerebral cortex continue to develop swiftly, establishing connections with one another and with the prefrontal cortex and lateralizing toward greater right-sided activation (Blankenship et al., 2017; Hopf et al., 2013). These changes make possible the dramatic gains in memory and spatial understanding of early and middle childhood—ability to use strategies to store and retrieve information, expansion of autobiographical memory (which brings an end to infantile amnesia), and drawing and reading of maps (which we will take up in Chapter 9). Advances in hippocampal development in school-age children and adolescents are associated with higher scores on measures of general intelligence and, in particular, with diverse memory skills (Daugherty, Flinn, & Ofen, 2017; Keresztes et al., 2017; Tamnes et al., 2018).

This child has been diagnosed with a rare condition in which part of the corpus callosum is absent. He has difficulty with tasks that have multiple steps and that require coordinated movements on both sides of the body. Here, a therapist helps him learn to tie shoes.

© PETER CIHELKA/THE FREE LANCE-STAR VIA AP IMAGES

Also located in the inner brain, adjacent to the hippocampus, is the amygdala, a structure that plays a central role in processing of novelty and emotional information. The amygdala is sensitive to facial emotional expressions, especially fear (Adolphs, 2010). It also enhances memory for emotionally salient events, thereby ensuring that information relevant for survival—stimuli that signify fear or safety—will be retrieved on future occasions. This capacity for emotional learning seems to emerge in early childhood: Extensive damage to the amygdala in the first few years leads to loss of ability to learn about fear and safety signals and wide-ranging socially inappropriate behaviors (Shaw, Brierley, & David, 2005). Throughout childhood and adolescence, connections between the amygdala and the prefrontal cortex, which governs regulation of emotion, form and myelinate (Gabard-Durnam et al., 2014; Tottenham, Hare, & Casey, 2009). Recall from Chapter 7 that in socially anxious children, the amygdala is overly reactive to threatening situations (see page 252 in Chapter 7).

The corpus callosum is a large bundle of fibers connecting the two cerebral hemispheres. Production of synapses and myelination of the corpus callosum are especially rapid in infancy and early childhood, then continue at a slower pace through middle childhood and adolescence (Tanaka-Arakawa et al., 2015). The corpus callosum supports smooth coordination of movements on both sides of the body and integration of many aspects of thinking, including perception, attention, memory, language, and problem solving. The more complex the task, the more essential is communication between the hemispheres.

Ask Yourself

Connect ■ What aspects of brain development support the tremendous gains in language, thinking, and motor control of early childhood?

Apply ■ Dental checkups revealed a high incidence of untreated tooth decay in a U.S. preschool program serving low-income children. Using findings presented in this and previous chapters, list possible contributing factors.

8.2 INFLUENCES ON PHYSICAL GROWTH AND HEALTH

8.2a Describe the effects of heredity, restful sleep, nutrition, and infectious disease on physical growth and health in early childhood.

8.2b Cite factors that increase the risk of unintentional injuries, and explain how childhood injuries can be prevented.

As we consider factors affecting growth and health in early childhood, you will encounter some familiar themes. Heredity remains influential, but environmental factors are also essential. In the sections that follow, we focus on the importance of sufficient restful sleep, good nutrition, relative freedom from disease, and physical safety. The limited material resources and constant stressors experienced by children growing up in poverty result in family conditions that are often deficient in these and other ways. As the Biology and Environment box above reveals, the extent to which poverty negatively affects brain structures undergoing rapid development in early childhood is the focus of intensive research.

Biology and EnvironmentChildhood Poverty and Brain Development

The profound threats posed to all domains of development by persistent childhood poverty are well documented: poorer physical health, impaired cognitive functioning, and emotional and behavior problems emerging in the early years that, without effective intervention, pose lifelong risks to overall competence and well-being (Duncan et al., 2012). Clear evidence also exists that environmental adversities associated with poverty—chronic high life stress; inadequate affection, involvement, and appropriate stimulation from parents; and poor nutrition—affect brain development.

Recall from Chapter 2 that 18 percent of U.S. children and adolescents live in families with incomes below the federal poverty level (the income judged necessary for a minimum living standard). Among children between birth and age 5, the U.S. poverty rate is even higher, at 21 percent, and it escalates to 50 percent in single-mother families with young children (U.S. Census Bureau, 2017a). While poverty negatively affects children of all ages, young children are particularly at risk. As we have seen in Chapter 5 and in this chapter, infancy and early childhood are sensitive periods during which brain structures governing cognitive and emotional abilities are developing especially rapidly, making them especially vulnerable to the effects of deficient experiences.

In a groundbreaking study, researchers asked whether atypical patterns of brain development might account for the link between childhood poverty and poorer cognitive outcomes. To answer this question, they capitalized on the rich data bank of the U.S. National Institutes of Health (NIH) Magnetic Resonance Imaging Study of Normal Brain Development (Hair et al., 2015). Nearly 400 4- to 18-year-olds, varying widely in family income and ethnicity, were assessed three times at two-year intervals. On each occasion, information on family background was gathered, and participants underwent MRI brain scans and took an array of cognitive tests. Factors that could otherwise explain a poverty–impaired brain development association, such as birth weight, family size, and maternal education, were carefully controlled.

The investigators focused on the volume of gray matter (darker tissue consisting mainly of neurons and their connective fibers) in several brain structures with lengthier periods of development and therefore likely to be vulnerable to adverse early experiences. They chose the frontal lobes, including the prefrontal cortex, important for executive processes such as control of attention, self-regulation, and thoughtful reflection; the temporal lobe, which supports language development; and the hippocampus, because of its crucial role in memory and processing of spatial information. At each age, participants’ gray matter volumes were compared to averages reflecting typical development, based on large numbers of individuals of the same age and sex.

Results revealed that children and adolescents growing up in the poorest families (those persistently below the federal poverty level) had gray matter volumes in the brain structures of interest that were 8 to 10 percent below average. Furthermore, atypical brain development accounted for 15 to 20 percent of their lower cognitive scores, when compared to the scores of economically better-off peers, on measures of vocabulary, verbal and spatial reasoning, concept formation, and reading and math achievement.

The children in this single-parent family are growing up in a southern Texas county with one of the lowest average incomes per person in the United States. Persistent poverty can compromise brain structures crucial for learning, school success, and a satisfying adult life.

© ROBERT NICKELSBERG/GETTY IMAGES

The NIH Study, along with similar investigations, confirms that persistent childhood poverty can compromise brain structures crucial for learning, school success, and a satisfying adult life (Johnson, Riis, & Noble, 2016; Noble et al., 2015). In other research, the effects of poverty on the developing brain were apparent as early as infancy, in reduced gray matter volumes and EEG brain-wave activity in the cerebral cortex (Hanson et al., 2013; Tomalski et al., 2013).

Of course, not all children living in poverty display the deficits in brain development and cognitive outcomes just described. Those with personal attributes and environmental supports that foster resilience often develop favorably (return to page 10 in Chapter 1 to review). Nevertheless, the power of poverty to undermine children’s optimal neurological and psychological functioning offers one of the strongest justifications for public policies aimed at reducing poverty and for early interventions that improve the environments of economically disadvantaged children.

8.2.1 Heredity and Hormones

Children’s physical size and rate of growth are related to those of their biological parents and siblings, making the impact of heredity on physical growth evident throughout childhood (Stulp & Barrett, 2016). Genes influence growth by controlling the body’s production of and sensitivity to hormones. Figure 8.2 on page 284 shows the pituitary gland, located at the base of the brain, which plays a critical role by releasing two hormones that induce growth.

The first, growth hormone (GH), is necessary from birth on for development of almost all body tissues. GH acts directly but also accomplishes its task with the help of an intermediary. It stimulates the liver and epiphyses of the skeleton to release another hormone called insulin-like growth factor 1 (IGF-1), which triggers cell duplication throughout the body, especially the skeleton, muscles, nerves, bone marrow (origin of blood cells), liver, kidney, skin, and lungs.

About 2 percent of children suffer from inherited conditions that cause either GH deficiency or IGF-1 deficiency (in which GH fails to stimulate IGF-1). Without medical intervention, such children reach an average mature height of only 4 to 4½ feet. When treated early with injections of GH or IGF-1 (depending on the disorder), they show catch-up growth and then grow at a typical rate, with most reaching an adult height within normal range (Pfäffle et al., 2018; Ranke & Wit, 2018).

The availability of synthetic GH has also made it possible to treat short, normal-GH children with hormone injections, in hopes of increasing their final height. Thousands of parents, concerned that their children will suffer social stigma because of their shortness, have sought this GH therapy. But most normal-GH children given GH treatment grow only slightly taller than their previously predicted mature height (Loche et al., 2014). And contrary to popular belief, normal-GH short children are not deficient in self-esteem or other aspects of psychological adjustment (Gardner & Sandberg, 2011). So despite the existence of “heightism” in Western cultures, little justification exists for medically intervening in short stature that is merely the result of biologically normal human diversity.

A second pituitary hormone, thyroid-stimulating hormone (TSH), prompts the thyroid gland in the neck to release thyroxine, which is necessary for brain development and for GH to have its full impact on body size. Infants born with inadequate thyroxine must receive it at once, or they will be intellectually disabled. Once the most rapid period of brain development is complete, children with too little thyroxine grow at a below-average rate, but the central nervous system is no longer affected (Wassner, 2017). With prompt treatment, such children catch up in body growth and eventually reach normal size.

These preschoolers are the same age but differ greatly in body size. Early treatment of growth hormone (GH) deficiency leads to substantial gains in height, but little justification exists for intervention with normal-GH children whose short stature simply reflects human diversity.

© ELLEN B. SENISI

8.2.2 Sleep Habits and Problems

Because GH is released during the child’s sleeping hours, sleep contributes to body growth. And a well-rested child is better able to play, learn, and contribute positively to family functioning. Many studies confirm that sleep difficulties are associated with impaired cognitive performance, including decreased attention, slower speed of thinking, poorer memory, and lower intelligence and achievement test scores, as well as with internalizing behavior problems (fear and anxiety) and externalizing behavior problems (anger and aggression). The impact of disrupted sleep on cognitive functioning and emotional adjustment is more pronounced for low-SES children. Perhaps insufficient sleep heightens the impact of other environmental stressors prevalent in their daily lives (Calhoun et al., 2017; Cellini, 2017; El-Sheikh et al., 2010, 2013). Also, children who sleep poorly disturb their parents’ sleep, which can generate significant family stress—a major reason that sleep difficulties are among the most frequent concerns parents raise with their preschooler’s doctor.

Total sleep declines in early childhood; on average, 2- and 3-year-olds sleep 11 to 12 hours, 4- to 6-year-olds 10 to 11 hours. But these averages encompass substantial individual variability, with lesser- or greater-than-average sleep remaining fairly stable over time (Jenni & Carskadon, 2012). Younger preschoolers typically take a 1- to 2-hour nap in the early afternoon, although daytime sleep need also varies widely. Some continue to take two naps, as they did in toddlerhood; others give up napping entirely.

Most European-American children stop napping between ages 3 and 4, although a quiet rest period after lunch helps them rejuvenate for the rest of the day. Perhaps because of greater cultural acceptance, napping remains common among African-American, Asian, and Hispanic children throughout early childhood, balanced by a tendency toward later bedtimes and less nighttime sleep (Crosby, LeBourgeois, & Harsh, 2005; Mindell et al., 2013). And napping at preschool enhances memories acquired earlier in the day, especially for children who nap regularly at home (Kurdziel, Duclos, & Spencer, 2013). Consequently, replacing nap opportunities with additional learning activities in early childhood programs may be counterproductive.

The majority of Western parents engage in bedtime routines with their preschoolers, though in the United States this is slightly more common among European-American than African-American and Hispanic parents. As noted in Chapter 5, bedtime routines are linked to reduced nighttime waking and longer total sleep time (see page 166). As in infancy and toddlerhood, during early childhood, European-American children are less likely to cosleep with their parents than their African-American and Hispanic agemates. European-American children more often go to bed with a security object, which may help them adjust to feelings of uneasiness at being left by themselves in a darkened room. In most cases, parent–child cosleeping is not associated with problems during the preschool years, other than more frequent night wakings of parents due to children’s movements (Worthman, 2011). Western cosleeping children generally ask to sleep in their own bed by age 6 or 7.

Difficulty falling asleep—calling to the parent or asking for another drink of water—is common in early childhood, occurring in about one-third of preschoolers. But European-American parents more often express concern about their child falling asleep at a regular time than do African-American parents, who, as just noted, report later bedtimes, shorter nighttime sleep durations, and more napping during the day (Milan, Snow, & Belay, 2007; Patrick, Millet, & Mindell, 2016). Perhaps European-American parents more highly value a scheduled bedtime and tend to view falling asleep without protest as a sign of their child’s maturity—expectations likely to be unmet at least occasionally.

In early childhood, as in toddlerhood, storybook reading and other bedtime routines are linked to reduced nighttime waking and longer total sleep times.

© GURPAL DUTTA/INDIAPICTURE/ALAMY Stock Photo

Sleep problems frequently result from inadequate parental control over young children’s TV, computer, video game, tablet, and smart phone use. As Figure 8.3 shows, the more weekly hours young children devote to screen media, the greater their number of parent-reported sleep disturbances—difficulty falling asleep, night wakings, restless sleep, inconsistent bedtimes and hours of sleep from night to night, and daytime fatigue (Mindell et al., 2013; Parent, Sanders, & Forehand, 2016). Among older children and adolescents, a similar relationship exists between screen media time and sleep disturbances. However, it takes fewer screen-time hours to disrupt young children’s sleep.

Sleep difficulties may also stem from a mismatch between parental demands and children’s biology. The parent may step up pressure on the child, who vigorously resists because of a lower-than-average need for sleep. Consequently, sleep interventions should include parent education about individual differences in young children’s sleep requirements (Johnson & Mindell, 2011). Intense bedtime struggles sometimes result from family turmoil, as children worry about how their parents may get along when they are asleep and not available to distract them. In these cases, addressing family stress and conflict is key to improving children’s sleep.

Finally, most children waken during the night from time to time, but those who cannot return to sleep on their own may suffer from a sleep disorder. Because young children have vivid imaginations and difficulty separating fantasy from reality, nightmares are common; half of 3- to 6-year-olds occasionally experience them. And about 4 percent of children are frequent sleepwalkers, who are unaware of their wanderings during the night. Gently awakening and returning the child to bed helps avoid self-injury. Sleep terrors, which affect 3 percent of young children, are perhaps the most upsetting sleep problem to parents. In these panic-stricken arousals from deep sleep, the child may scream, thrash, speak incoherently, show a sharp rise in heart rate and breathing, and initially be unresponsive to parents’ attempts to comfort. Sleepwalking and sleep terrors tend to run in families, suggesting a genetic influence (Moore & Mindell, 2012; Ophoff et al., 2018). But they can also be triggered by stress or extreme fatigue.

Fortunately, sleep disorders of early childhood usually subside without treatment. In the few cases that persist, children require a medical and psychological evaluation. Their disturbed sleep may be a sign of neurological or emotional difficulties.

Figure 8.3 Relationship between hours devoted to screen media and sleep disturbances among young children. Several hundred parents of 3- to 7-year-olds were asked how much daily time over a typical week their child spent watching TV or videos, using a computer, playing video games, using a tablet, and using a smartphone for activities other than talking on the phone. Parents also rated their child’s frequency of sleep disturbances for the most recent typical week. A positive relationship between screen time and sleep disturbances emerged, with a steep increase in parent-reported sleep problems after six daily hours devoted to screen media. (Based on Parent, Sanders, & Forehand, 2016.)

8.2.3 Nutrition

As children approach age 2, many become unpredictable, picky eaters. One father I know wistfully recalled how his son as a toddler eagerly sampled Chinese food: “He ate rice, chicken chow mein, egg rolls—and now, at age 3, the only thing he’ll try is the ice cream!”

Preschoolers’ appetites decline because their growth has slowed. Their wariness of new foods is also adaptive: If they stick to familiar foods, they are less likely to swallow dangerous substances when adults are not around to protect them. With the transition to middle childhood, picky eating usually subsides (Birch & Fisher, 1995; Cardona Cano et al., 2015). Parents need not worry about variations in amount eaten from meal to meal. Over the course of a day, preschoolers compensate for eating little at one meal by eating more at a later one (Hursti, 1999).

Though they eat less, preschoolers need a high-quality diet, including the same variety of foods adults need, but in smaller amounts. These include milk and milk products, meat or meat alternatives (such as eggs, dried peas or beans, and peanut butter), vegetables and fruits, and breads and cereals. Fats, oils, and salt are best kept to a minimum because of their link to high blood pressure and heart disease in adulthood. And foods high in sugar should be eaten only in small amounts to prevent tooth decay and protect against overweight and obesity—a topic we will take up in Chapter 11.

Children tend to imitate the food choices and eating practices of people they admire, both adults and peers. For example, in Mexico, where children see family members delighting in the taste of peppery foods, preschoolers enthusiastically eat chili peppers, whereas most U.S. children reject them. Simply offering a new food, with repeated, unpressured opportunities to taste it over 5 to 15 mealtime exposures, is highly effective in getting young children to accept it (Lam, 2015). And pleasant prompts combined with reasoning can boost preschoolers’ willingness to eat a new vegetable: “This squash tastes like sweet potatoes, so you might like it” (Edelson, Mokdad, & Martin, 2016).

Providing occasions for children to become visually familiar with the food is helpful as well. In one study, researchers randomly assigned parents varying in SES to a treatment in which they joined their preschooler in looking at a picture book featuring an unfamiliar vegetable once a day for two weeks. Over a second two-week period, the parents offered their child a daily taste of the food. Compared to a no-book control group, parents in the picture-book group reported experiencing more pleasure at introducing their child to the new vegetable, and their children were more willing to taste it, expressed greater liking for it, and ate more of it (Houston-Price et al., 2019). At a three-month follow-up, children in the picture-book group continued to eat more of the food.

Unfortunately, parents who dislike vegetables and other healthy foods usually don’t offer them to their children (Boles et al., 2014). Children in such families consume a restricted variety of foods and eat a less healthy diet. Yet mothers who say they don’t like vegetables but still offer them regularly generally report that their child likes them (Kaar et al., 2016).

A preschooler helps his mother prepare a traditional treat for a Chinese festival: sweet rice dumplings wrapped in bamboo leaves. Children tend to imitate the food preferences of those they admire—both adults and peers.

© MAAHOO STUDIO/GETTY IMAGES

The emotional climate at mealtimes has a powerful impact on children’s eating habits. When parents are worried about how well their preschoolers are eating, meals can become unpleasant and stressful. Coercing children to eat—for example, by offering bribes, such as “Finish your vegetables, and you can have an extra cookie”—leads children to like the healthy food less and the treat more (Birch, Fisher, & Davison, 2003). Similarly, restricting access to tasty foods focuses children’s attention on those foods and increases their desire to eat them. In a study of nearly 5,000 Dutch 4-year-olds, maternal feeding practices were strongly associated with children’s unhealthy weight, in both directions. The more mothers reported pressuring their child to eat, the greater the likelihood of an underweight child. And the more mothers reported restricting their child’s eating, the greater the chances of an overweight or obese child (see Figure 8.4) (Jansen et al., 2012). Too much parental control over eating seems to interfere with children’s responsiveness to hunger cues, resulting either in withdrawal from food or in excessive eating.

Applying What We Know

Encouraging Good Nutrition in Early Childhood

Suggestion

Description

Offer a varied, healthy diet.

Provide a well-balanced variety of nutritious foods that are colorful and attractively served. Avoid including sweets and “junk” foods in the child’s regular food environment.

Offer predictable meals as well as several snacks each day.

Preschoolers’ stomachs are small, and they may not be able to eat enough in three meals to satisfy their energy requirements. They benefit from extra opportunities to eat.

Offer small portions, and permit the child to serve him- or herself and to ask for seconds.

When too much food is put on the plate, preschoolers (like adults) often overeat, increasing the risk of obesity. On average, preschoolers consume 25 percent less at a meal when permitted to serve themselves.

Offer healthy new foods early in a meal and repeatedly at subsequent meals, and respond with patience if the child rejects the food.

Introduce healthy new foods before the child’s appetite is satisfied. Let children see you eat and enjoy the new food. When prompting the child to try the food, use reasoning: “Prunes are like big raisins, so you might like them.” If the child rejects the food, accept the refusal and serve it again at another meal. As foods become more familiar, they are more readily accepted.

Keep mealtimes pleasant, include the child in mealtime conversations, and refrain from coercing the child to eat.

A pleasant, relaxed eating environment helps children develop positive attitudes about food. Refrain from constantly offering food, pressuring the child to eat, or engaging in confrontations over disliked foods and table manners—practices associated with children’s refusal to eat.

Avoid using food as a reward and restricting access to certain foods.

Saying “No dessert until you clean your plate” tells children that they must eat even if they are not hungry and that dessert is the best part of the meal. Restricting access to a food increases children’s valuing of that food and efforts to obtain it.

Sources: Jansen et al., 2012; Kaar et al., 2016.

Figure 8.4 Relationship of maternal feeding practices to underweight, overweight, and obesity among preschoolers. In a Dutch study of nearly 5,000 4-year-olds, mothers who pressured their child to eat were more likely to have an underweight child. Mothers who restricted their child’s eating increased their chances of having an overweight or obese child. These relationships held even after controlling for many factors that could have influenced maternal feeding practices and preschoolers’ weight gain, including parents’ SES, ethnicity, height and weight, and children’s enjoyment of eating. (Based on Jansen et al., 2012.)

Food preferences and eating patterns acquired in early childhood remain relatively stable through adolescence and adulthood (Mikkila et al., 2005; Northstone & Emmett, 2008).Thus, the preschool years are a window of opportunity for establishing good eating practices, with potentially lifelong health benefits. For ways to encourage healthy, varied eating in young children, refer to Applying What We Know above.

Finally, as indicated in earlier chapters, many children in the United States and in developing countries lack access to sufficient high-quality food to support healthy growth. Five-year-old Hal rode a bus from a poverty-stricken neighborhood to our laboratory preschool. His mother’s paycheck barely covered her rent, let alone food. Hal’s diet was deficient in protein and in essential vitamins and minerals—iron (to prevent anemia), calcium (to support development of bones and teeth), zinc (to support immune system functioning, neural communication, and cell duplication), vitamin A (to help maintain eyes, skin, and a variety of internal organs), and vitamin C (to facilitate iron absorption and wound healing). These are the most common dietary deficiencies of the preschool years (Yousafzai, Yakoob, & Bhutta, 2013).

Hal was small for his age, pale, inattentive, and disruptive at preschool. Throughout childhood and adolescence, a nutritionally deficient diet is associated with shorter stature, attention and memory difficulties, poorer intelligence and achievement test scores, and hyperactivity and aggression, even after family factors that might account for these relationships (such as stressors, parental psychological health, education, warmth, and stimulation of the child) are controlled (Lukowski et al., 2010; Prado & Dewey, 2014).

Look and Listen

Arrange to join a family with at least one preschooler for a meal, and closely observe parental mealtime practices. Are they likely to promote healthy eating habits? Explain.

8.2.4 Infectious Disease

One day, I noticed that Hal had been absent from the play yard for several weeks, so I asked Leslie, his preschool teacher, what was wrong. “Hal’s been hospitalized with the measles,” she explained. “He’s had difficulty recovering—lost weight when there wasn’t much to lose in the first place.” In well-nourished children, ordinary childhood illnesses have no effect on physical growth. But when children are undernourished, disease interacts with malnutrition in a vicious spiral, with potentially severe consequences.

Infectious Disease and Malnutrition

Hal’s reaction to the measles is commonplace in developing nations, where a large proportion of the population lives in poverty and children do not receive routine immunizations. Illnesses such as measles and chickenpox, which typically do not appear until after age 3 in industrialized nations, occur much earlier. Poor diet depresses the body’s immune system, making children far more susceptible to disease. Of the 5.9 million annual deaths of children under age 5 worldwide, 98 percent are in developing countries, and about half are due to infectious diseases (UNICEF, 2017b).

Disease, in turn, is a major contributor to malnutrition, hindering both physical growth and cognitive development. Illness reduces appetite and limits the body’s ability to absorb foods, especially in children with intestinal infections. In developing countries, widespread diarrhea, resulting from unsafe water and contaminated foods, leads to stunted growth and an estimated 400,000 to 700,000 childhood deaths each year, with children under age 5 most affected (Glass & Stoll, 2018; Mokomane et al., 2018). Studies carried out in low-income countries reveal that the more persistent diarrhea is in early childhood, the shorter children are in height and the lower their intelligence test scores during the school years (Black, 2017; Pinkerton et al., 2016).

Most developmental impairments and deaths due to diarrhea can be prevented with nearly cost-free oral rehydration therapy (ORT), in which sick children are given a glucose, salt, and water solution that quickly replaces fluids the body loses. Since 1990, public health workers have taught many families in the developing world how to administer ORT. Also, low-cost supplements of zinc (essential for immune system functioning) substantially reduce the incidence of severe and prolonged diarrhea, especially when combined with ORT (World Health Organization, 2018). Through these interventions, the lives of millions of children are saved each year.

A public health worker teaches a Haitian mother how to prepare oral rehydration therapy (ORT) for her child, who is suffering from diarrhea. This nearly cost-free treatment saves the lives of millions of children in developing countries each year.

Shehzad Noorani/ Majority World

Immunization

In industrialized nations, childhood diseases have declined dramatically during the past half century, largely as a result of widespread immunization of infants and young children. Hal got the measles because, unlike his classmates from more advantaged homes, he did not receive a full program of immunizations.

In the United States, routine childhood immunizations have prevented an estimated 20 million illnesses and 40,000 deaths each year (Ventola, 2016). Yet about 28 percent of U.S. 1½- to 3-year-olds lack one or more essential immunizations. The rate rises to 32 percent for poverty-stricken children, many of whom do not receive full protection until ages 5 or 6, when it is required for school entry (Centers for Disease Control and Prevention, 2017c). In contrast, fewer than 10 percent of preschoolers lack immunizations in Australia, Denmark, and Norway, and fewer than 5 percent in Canada, the Netherlands, Sweden, and the United Kingdom (World Health Organization, 2017b).

Why does the United States lag behind these countries in immunization? Although the U.S. Affordable Care Act of 2010 greatly improved health insurance coverage for American children, many low-income children remain without coverage (see page 76 in Chapter 2) and, therefore, may not receive timely vaccinations. Beginning in 1994, all U.S. children whose parents are unable to pay were guaranteed free immunizations, a program that has led to gains in immunization rates.

Inability to afford vaccines is not the only cause of inadequate immunization. Parents with little education and with stressful daily lives often fail to schedule vaccination appointments. Some parents have been influenced by media reports—now widely discredited—suggesting a link between the measles–mumps–rubella vaccine and a rise in the number of children diagnosed with autism. In fact, numerous large-scale studies show no association (Maglione et al., 2014; Ventola, 2016). Other parents have religious or philosophical objections—for example, the belief that children should develop immunities naturally.

A 4-year-old in the Netherlands reacts to receiving an essential immunization at a mass vaccination event in his community. The Netherlands has one of the highest early childhood vaccination rates in the world.

© ED OUDENAARDEN/Getty Images

In areas where many parents refuse to immunize their children, disease outbreaks have occurred, with life-threatening consequences (Salmon et al., 2015). Public education programs directed at increasing parental knowledge about the importance and safety of timely immunizations, and convenient opportunities to obtain them free or at low cost, are badly needed. The Netherlands achieves its high child immunization rate by giving parents of every newborn baby a written schedule that shows exactly when and where the child should be immunized (Lernout et al., 2013). If a parent does not bring the child at the specified time, a public health nurse goes to the home to ensure that the child remains in step with the schedule.

A final point regarding communicable disease in early childhood deserves mention. Childhood illness rises with child-care attendance. On average, an infant or toddler in child care becomes sick 9 to 10 times a year, a preschooler 6 to 7 times. The diseases that spread most rapidly are those most frequently suffered by young children—diarrhea and respiratory infections (Shope, 2014). The risk that a respiratory infection will result in otitis media, or middle ear infection, is greatly elevated. To learn about the consequences of otitis media and how to prevent it, consult the Social Issues: Health box on the following page.

8.2.5 Childhood Injuries

More than any other child in the preschool classroom, 3-year-old Tommy had trouble sitting still and paying attention. Instead, he darted from one place and activity to another. One day, he narrowly escaped serious injury when he put his mother’s car in gear while she was outside scraping ice from its windows. The vehicle rolled through a guardrail and over the side of a 10-foot concrete underpass, where it hung until rescue workers arrived. Police charged Tommy’s mother with failing to use a restraint seat for a child younger than age 8.

Unintentional injuries are the leading cause of childhood mortality in industrialized nations. Although U.S. childhood injury fatalities have declined steadily over the past four decades due to state laws and community policies aimed at improving child safety, the United States nevertheless ranks poorly among Western nations in these largely preventable events. About 29 percent of U.S. deaths between ages 1 and 14 and 75 percent of deaths between ages 15 and 19 result from injuries, causing about 8,000 children and youths to die annually (Centers for Disease Control and Prevention, 2018c). Among the hundreds of thousands who survive, many suffer pain, brain damage, and permanent physical disabilities.

Social Issues: HealthOtitis Media and Development

During his first year in child care, 2-year-old Alex caught five colds, had the flu on two occasions, and experienced repeated otitis media (middle-ear infection). Alex is not unusual. By age 3, 80 percent of children have had respiratory illnesses that resulted in at least one bout of otitis media; nearly half of these have had three or more bouts (Marom et al., 2014). Although antibiotics eliminate the bacteria responsible for otitis media, they do not reduce fluid buildup in the middle ear, which causes mild to moderate hearing loss that can last for weeks or months.

The incidence of otitis media is greatest between 6 months and 3 years, when children are first acquiring language. Frequent infections predict delayed language progress in early childhood, and poorer academic performance (including reading deficits) after school entry (Racanello & McCabe, 2010).

How might otitis media disrupt language and academic progress? Difficulties in perceiving and processing speech sounds, particularly in noisy settings, may be responsible. Children with many bouts are less attentive to others’ speech and less persistent at tasks (Asbjornsen et al., 2005; Cai & McPherson, 2017; Carroll & Breadmore, 2018). Their distractibility may result from an inability to make out what people around them are saying—which, in turn, may reduce the quality of others’ interactions with them.

Because otitis media is so widespread, current evidence argues strongly in favor of early prevention. Crowded living conditions and exposure to cigarette smoke and other pollutants are linked to the disease, probably accounting for its high incidence among low-SES children (Bartholomew, 2015; Jang, Jun, & Park, 2016). And compared with children remaining at home, rates of otitis media nearly double in children who attend child-care centers, where severe, antibacterial-resistant strains of respiratory infections can easily develop and spread. Risk increases further with the number of daily child-care settings a child experiences, which magnifies the number of peers with whom the child comes in contact (Morrissey, 2013).

Early otitis media can be prevented in the following ways:

Frequent screening for the disease, followed by prompt medical intervention. Plastic tubes that drain the narrow Eustachian tubes of the middle ear often are used to treat repeated episodes of otitis media in children, although their effectiveness is uncertain (Venekamp et al., 2018).

Child-care settings that control infection. Because infants and young children often put toys in their mouths, these objects should be rinsed frequently with a disinfectant. Pacifier use has also been linked to a greater risk of otitis media (Nelson, 2012). Spacious, well-ventilated rooms and small group sizes help limit spread of the disease.

Otitis media is widespread among children who attend child-care centers, where close contact leads to rapid spread of respiratory infections.

© LAURA DWIGHT PHOTOGRAPHY

Verbally stimulating adult–child interaction. Developmental problems associated with otitis media are reduced or eliminated in high-quality child-care centers (Vernon-Feagans et al., 2007). When caregivers are verbally stimulating and keep noise to a minimum, children have more opportunities to hear, and benefit from, spoken language.

Vaccines. Many cases of otitis media are associated with pneumonia and influenza infection, making pneumonia immunization in infancy and annual flu vaccination effective preventive measures (Principi, Baggi, & Esposito, 2012; Sigurdsson et al., 2018).

Auto and traffic accidents, suffocation, drowning, and poisoning are the most common injuries resulting in childhood deaths (Safe Kids Worldwide, 2015). Motor vehicle collisions are by far the most frequent overall source of injury. They rank as the second leading U.S. cause of mortality from birth to age 5 (after suffocation among infants and drowning among toddlers and preschoolers) and as the leading cause among school-age children and adolescents.

Factors Related to Childhood Injuries

The common view of childhood injuries as “accidental” suggests that they are due to chance and cannot be prevented. In fact, these injuries occur within a complex ecological system of individual, family, community, and societal influences—and we can do something about them.

As Tommy’s case suggests, individual differences exist in the safety of children’s behaviors. Because of their higher activity level and greater impulsivity and risk taking, boys are nearly twice as likely as girls to be injured, and their injuries are more severe (Merrick, 2016). Parents realize that they need to take more steps to protect their young sons than daughters from injury, and most do so. Still, mothers judge that they are less likely to succeed in preventing injuries in sons than in daughters (Morrongiello & Kiriakou, 2004; Morrongiello, Ondejko, & Littlejohn, 2004). This belief may keep them from sufficiently monitoring the most injury-prone boys.

Children with certain temperamental and personality characteristics—inattentiveness, overactivity, irritability, defiance, and aggression—are also at greater risk for injuries (Ordonana, Caspi, & Moffitt, 2008; Schwebel & Gaines, 2007). As we saw in Chapter 7, these children present child-rearing challenges. They are likely to protest when placed in auto seat restraints, to refuse to take a companion’s hand when crossing the street, and to disobey after repeated instruction and discipline.

Poverty, single parenthood, and low parental education are also strongly associated with injury (Dudani, Macpherson, & Tamim, 2010; Schwebel & Brezausek, 2007). Parents who must cope with many daily stressors often have little time or energy to monitor the safety of their children. And their homes and neighborhoods are likely to be noisy, crowded, and rundown, posing further risks.

Childhood injury rates are highest in areas with extensive poverty, lack of high-quality child care, and weak parental vigilance, as illustrated by these children’s makeshift playground.

© JEFTA IMAGES/BARCROFT MEDIA/GETTY IMAGES

Broad societal conditions also affect childhood injury. In developing countries, the rate of childhood deaths from injuries is far greater than in developed nations and soon may exceed disease as the leading cause of childhood mortality (Kahn et al., 2015). Rapid population growth, overcrowding in cities, and heavy road traffic combined with weak safety measures are major causes. Safety devices, such as car safety seats and bicycle helmets, are neither readily available nor affordable.

Childhood injury rates are high in the United States because of extensive poverty, shortages of high-quality child care (to supervise children in their parents’ absence), and a high rate of births to teenagers, who are neither psychologically nor financially ready for parenthood (Child Trends, 2014a; Höllwarth, 2013). But U.S. children from economically advantaged families are also at considerably greater risk for injury than children in other Western nations. This indicates that besides reducing poverty and teenage parenthood and upgrading the status of child care, additional steps are needed to ensure children’s safety.

Preventing Childhood Injuries

Childhood injuries have many causes, so a variety of approaches are needed to control them. Laws prevent many injuries, for example, by requiring car safety seats, child-resistant caps on medicine bottles, flameproof clothing, and fencing around backyard swimming pools—the site of 50 percent of early childhood drownings. Communities can help by modifying their physical environments. Providing inexpensive and widely available public transportation can reduce the amount of time that children spend in cars. Playgrounds, a common site of injury, can be covered with protective surfaces. Free, easily installed window guards can be given to families in high-rise apartment buildings to prevent falls. And media campaigns can inform parents and children about safety issues.

But even though they know better, many parents and children behave in ways that compromise safety. During the past several decades, U.S. parents have changed very little in how much they do to protect their children, citing such reasons as “the chances of serious injury are slim,” taking necessary steps “is a hassle,” and (among low-income families) safety devices (such as home fire extinguishers and bicycle helmets) “cost too much.” For example, about 27 percent of U.S. parents (like Tommy’s mother) fail to place their children in car safety seats, and nearly 75 percent of infant seats and 40 percent of child booster seats are improperly used (Macy et al., 2015). Yet research confirms that young children properly restrained in car safety seats have a 70 to 80 percent reduced risk of injury in a crash (Centers for Disease Control and Prevention, 2017b). American parents, especially, seem willing to ignore familiar safety practices, perhaps because of the high value they place on individual rights and personal freedom.

Parental attention to straightforward precautions—such as properly securing children in car safety seats—can substantially reduce childhood injury rates.

© DEX IMAGES/GETTY IMAGES

Furthermore, many parents overestimate young children’s knowledge of safety rules and consequently pull back from monitoring and controlling their access to hazards—a premature transition associated with a rise in home injuries. When parents teach safety rules to preschoolers, they often do so as a reaction to unsafe behaviors, rather than as an advance preventive. And they frequently fail to explain the basis for the rules—despite evidence that explanations enhance children’s retention, understanding, and compliance (Morrongiello, Ondejko, & Littlejohn, 2004; Morrongiello et al., 2014). Even with well-learned rules, preschoolers need supervision to ensure that they comply.

Applying What We Know

Reducing Unintentional Injuries in Early Childhood

Suggestion

Description

Provide age-appropriate supervision and safety instruction.

Despite gains in understanding and self-control, preschoolers need nearly constant supervision. To encourage children to remember and obey safety rules, establish the rules, explain the reasons behind them, consistently enforce them, and praise children for following them.

Know the child’s temperament.

Children who are unusually active, distractible, negative, or curious have more than their share of injuries and need extra monitoring.

Eliminate the most serious dangers from the home.

Examine all spaces for safety. For example, in the kitchen, store dangerous products in high cabinets out of sight, and keep sharp implements in a latched drawer. Remove guns; if that is impossible, store them unloaded in a locked cabinet. Always accompany young preschoolers to the bathroom, and keep all medicines in containers with safety caps.

During automobile travel, always restrain the child properly in the back seat of the car.

Use an age-appropriate, properly installed car safety seat or booster seat until the child is at least 4 feet 9 inches tall and 8 to 12 years of age, and strap the child in correctly every time. Children should always ride in the back seat; passenger-side air bags in the front seat deploy so forcefully that they can cause injury or death to a child. Never leave a child alone in a car, even on a cool, sunny day; a child’s core body temperature increases 3 to 5 times faster than an adult’s, with risk of permanent injury or death.

Select safe playground equipment and sites.

Make sure sand, wood chips, or rubberized matting has been placed under swings, see-saws, slides, and jungle gyms and that all playground equipment is well-maintained. Check yards for dangerous plants. Always supervise outdoor play.

Be extra cautious around water.

Constantly observe children during water play; even shallow, inflatable pools are frequent sites of drownings. While they are swimming, young children’s heads should not be immersed in water; they may swallow so much that they develop water intoxication, which can lead to convulsions and death.

Practice safety around animals.

Wait to get a pet until the child is mature enough to handle and help care for it—usually around ages 5 or 6. Never leave a young child alone with an animal; bites often occur during playful roughhousing. Model and teach humane pet treatment.

Source: Centers for Disease Control and Prevention, 2017f.

Interventions aimed at parents that highlight risk factors and that model and reinforce safety practices are effective in reducing home hazards and childhood injuries (Kendrick et al., 2008). Family conditions associated with childhood injuries must be similarly addressed: relieving crowding in the home, providing social supports to ease parental stress, and teaching parents to use effective discipline—a topic we will take up in Chapter 10. Positive parenting—an affectionate, supportive relationship with the child; consistent, reasonable expectations for maturity; and oversight to ensure safety-rule compliance—substantially reduces injury rates, especially in overactive, emotionally reactive, and impulsive children. And in two-parent households, effective coparenting combined with both parents’ involvement with young children are helpful as well (Nepomnyaschy & Donnelly, 2015; Schwebel & Gaines, 2007). But to implement these strategies, parents must have sufficient time and emotional resources along with relevant knowledge and skills. Refer to Applying What We Know above for ways to minimize unintentional injuries in early childhood.

Ask Yourself

Connect ■ Using research on malnutrition or unintentional injuries, show how physical growth and health in early childhood result from a continuous, complex interplay between heredity and environment.

Apply ■ One day, Leslie prepared a new snack to serve at preschool: celery stuffed with ricotta cheese and pineapple. The first time she served it, few children touched it. How can Leslie encourage the children to accept the snack? What tactics should she avoid?

Reflect ■ Ask a parent or other family member whether, as a young child, you were a picky eater, suffered from sleep problems, or sustained any serious injuries. In each instance, what factors might have been responsible?

8.3 MOTOR DEVELOPMENT

8.3a Cite major milestones of gross- and fine-motor development in early childhood.

8.3b Describe individual differences in preschoolers’ motor skills and ways to enhance motor development in early childhood.

Observe several 2- to 6-year-olds at play in a neighborhood park, preschool, or child-care center. You will see that an explosion of new motor skills occurs in early childhood, each of which builds on the simpler movement patterns of toddlerhood.

During the preschool years, children continue to integrate previously acquired skills into more complex, dynamic systems. Then they revise each new skill as their bodies grow larger and stronger, their central nervous systems develop, their environments present new challenges, and they set new goals, aided by gains in perceptual and cognitive capacities.

8.3.1 Gross-Motor Development

As children’s bodies become more streamlined and less top-heavy, their center of gravity shifts downward, toward the trunk. As a result, balance improves greatly, paving the way for new motor skills involving large muscles of the body. By age 2, preschoolers’ gaits become smooth and rhythmic—secure enough that soon they leave the ground, at first by running and later by jumping, hopping, galloping, and skipping.

As children become steadier on their feet, their arms and torsos are freed to experiment with new skills—throwing and catching balls, steering tricycles, and swinging on horizontal bars and rings. Then upper- and lower-body skills combine into more refined actions. Five- and 6-year-olds simultaneously steer and pedal a tricycle and flexibly move their whole body when throwing, catching, hopping, and jumping. By the end of the preschool years, all skills are performed with greater speed and endurance. Table 8.1 provides a closer look at gross-motor development in early childhood.

Changes in ball skills provide an excellent illustration of preschoolers’ gross-motor progress. Young preschoolers stand still, facing the target, throwing with their arm thrust forward (see Figure 8.5a). Catching is equally awkward. Two-year-olds extend their arms and hands rigidly, using them as a single unit to trap the ball. By age 3, children flex their elbows enough to trap the ball against the chest. But if the ball arrives too quickly, they cannot adapt, and it may bounce off the body (Haywood & Getchell, 2014).

Gradually, children call on the shoulders, torso, trunk, and legs to support throwing and catching. By age 4, children rotate the body and take a step forward to add force to their throw. Around 5 to 6 years, they begin by shifting their weight to a rear foot in a preparatory backswing and then shift forward, rotating the trunk and stepping into the throw as they release the ball (see Figure 8.5b). As a result, the ball travels faster and farther. When the ball is returned, older preschoolers predict its place of landing by moving forward, backward, or sideways. Soon, they can catch the ball with their hands and fingers, “giving” with arms and body to absorb the force of the ball.

Look and Listen

Play a game of catch with a 2- to 3-year-old, then with a 4- to 6-year-old. What differences in movement and coordination are evident?

Table 8.1 Changes in Gross- and Fine-Motor Skills During Early Childhoo

Age

Gross-Motor Skills

Fine-Motor Skills

2–3 years

Walks more rhythmically; hurried walk changes to run

Jumps, hops, throws, and catches with rigid upper body

Pushes riding toy with feet; little steering

Puts on and removes simple items of clothing

Zips and unzips large zippers

Uses spoon effectively

3–4 years

Walks up stairs, alternating feet, and down stairs, leading with one foot

Jumps and hops, flexing upper body

Throws and catches with slight involvement of upper body; still catches by trapping ball against chest

Pedals and steers tricycle

Fastens and unfastens large buttons

Serves self food without assistance

Uses scissors

Copies vertical line and circle

Draws first picture of person, using tadpole image

4–5 years

Walks down stairs, alternating feet

Runs more smoothly

Gallops and skips with one foot

Throws ball with increased body rotation and transfer of weight from one foot to the other; catches ball with hands

Rides tricycle rapidly, steers smoothly

Uses fork effectively

Cuts with scissors following line

Copies triangle, cross, and some letters

5–6 years

Increases running speed to 12 feet per second

Gallops more smoothly; engages in true skipping

Displays mature throwing and catching pattern

Rides bicycle with training wheels

Uses knife to cut soft food

Ties shoes

Draws person with six parts

Copies some numbers and simple words

Sources: Haywood & Getchell, 2014; Malina & Bouchard, 1991.

8.3.2 FiSne-Motor Development

Like gross-motor development, fine-motor skills take a giant leap forward in the preschool years. As control of the hands and fingers improves, young children put puzzles together, build with small blocks, cut and paste, string beads, and use touch screens adeptly. To parents, fine-motor progress is most apparent in two areas: (1) children’s care of their own bodies, and (2) the drawings and paintings that fill the walls at home, child care, and preschool.

Figure 8.5 Changes in throwing during early childhood. At age 2 to 3, children stand still, simply bringing the hand back and throwing rigidly without taking a step. Gradually, they involve the entire body. By age 5 to 6, they typically engage in arm, leg, and trunk rotation and preparatory action before executing the throw. Integrated throwing movements become increasingly refined and adapted to the throwing situation during middle childhood. (Adapted figures drawn from film tracings taken in the Motor Development and Child Study Laboratory, University of Wisconsin–Madison and now available from the Motor Development Film Collection, Kinesiology Division, Bowling Green State University. © Mary Ann Roberton. Reprinted by permission of Mary Ann Roberton).

Self-Help Skills

As Table 8.1 shows, young children gradually become self-sufficient at dressing and feeding. Two-year-olds put on and take off simple items of clothing. By age 3, children can dress and undress well enough to take care of toileting needs by themselves. Between ages 4 and 5, children can dress and undress without supervision. At mealtimes, young preschoolers use a spoon well, and they can serve themselves. By age 4 they are adept with a fork, and around 5 to 6 years they can use a knife to cut soft foods. Roomy clothing with large buttons and zippers and child-sized eating utensils help children master these skills.

Preschoolers get great satisfaction from managing their own bodies. They are proud of their independence, and their new skills also make life easier for adults. But parents must be patient about these abilities: When tired and in a hurry, young children often revert to eating with their fingers. And the 3-year-old who dresses himself in the morning sometimes ends up with his shirt on inside out, his pants on backward, and his left snow boot on his right foot! Perhaps the most complex self-help skill of early childhood is shoe tying, mastered around age 6. Success requires a longer attention span, sufficient working memory to hold in mind an intricate series of hand movements, and the dexterity to perform them. Shoe tying illustrates the close connection between motor and cognitive development, as do two other skills: drawing and writing.

Preschoolers gradually become more proficient at self-help skills of dressing and feeding themselves. Most master shoe tying, the most complex self-help skill, around age 6.

© LAURA DWIGHT PHOTOGRAPHY

Drawing

When given crayon and paper, even toddlers scribble in imitation of others. And after being shown by an adult how to use a smartphone drawing app to select a color from a palette and draw on the screen, children as young as age 2 can use it to scribble (Yadav & Chakraborty, 2017). As the young child’s ability to mentally represent the world expands, markings on the page or screen take on meaning. A variety of factors combine with fine-motor control in the development of children’s artful representations (Golomb, 2004). These include the realization that pictures can serve as symbols, improved planning and spatial understanding, and the emphasis that the child’s culture places on artistic expression.

Typically, drawing progresses through the following sequence:

Scribbles. As long as drawing materials are available, many children begin to draw during the second year. At first, the intended representation is contained in gestures rather than in the resulting marks on the page. For example, one 22-month-old rapidly made some dots on a page and explained, “Crayon running!”

Recall from Chapter 6 that 2-year-olds treat realistic-looking pictures symbolically (see page 205 in Chapter 6). However, they have difficulty interpreting line drawings. When an adult held up a drawing indicating which of two objects preschoolers should drop down a chute, 3-year-olds used the drawing as a symbol to guide their behavior, but 2-year-olds did not (Callaghan, 1999).

First representational forms. Around age 3, children’s scribbles start to become pictures. Often children make a gesture with the crayon, notice that they have drawn a recognizable shape, and then label it. In one case, a 2-year-old made some random scribbles and then, realizing the resemblance between his scribbles and noodles, named the creation “chicken pie and noodles” (Winner, 1986).

Few 3-year-olds spontaneously draw so others can tell what their picture represents. However, after an adult demonstrated how drawings can be used to stand for objects in a game, more 3-year-olds drew recognizable forms (Callaghan & Rankin, 2002). Western parents and teachers spend much time promoting 2- and 3-year-olds’ language and make-believe play but relatively little time showing them how they can use drawings to represent their world (Cohn, 2014). When adults draw with children and point out resemblances between drawings and objects, preschoolers’ pictures become more comprehensible and detailed (Braswell & Callanan, 2003).

Figure 8.6 Examples of young children’s drawings. The universal tadpolelike shape that children use to draw their first picture of a person is shown on the left. The tadpole soon becomes an anchor for details such as arms, fingers, toes, and facial features that sprout from the basic shape. By the end of the preschool years, children produce more complex, differentiated pictures like the one on the right by a 5-year-old child. (Left: From H. Gardner, 1980, Artful Scribbles: The Significance of Children’s Drawing, New York: Basic Books, p. 64. Copyright © 1980 by Howard Gardner. Reprinted by permission of Basic Books, an imprint of Perseus Books, conveyed through Copyright Clearance Center. Right: © Children’s Museum of the Arts New York, Permanent Collection.)

Look and Listen

Visit a preschool or child-care center where artwork by 3- to 5-year-olds is plentiful. Note developmental progress in drawings of human and animal figures and in the complexity of children’s pictures.

A major milestone in drawing occurs when children use lines to represent the boundaries of objects, enabling 3- and 4-year-olds to draw their first picture of a person. Fine-motor and cognitive limitations lead preschoolers to reduce the figure to the simplest form that still looks human: the universal “tadpole” image, a circular shape with lines attached, shown on the left in Figure 8.6, produced by children from widely differing cultures (Gernhardt, Rübeling, & Keller, 2014; Rübeling, 2014). Four-year-olds add features, such as eyes, nose, mouth, hair, fingers, and feet, as the tadpole drawings illustrate.

More realistic drawings. Five- and 6-year-olds create more complex drawings, like the one on the right in Figure 8.6, containing more conventional human and animal figures, with the head and body differentiated. Older preschoolers’ drawings still contain perceptual distortions because they have just begun to represent depth. Use of depth cues, such as overlapping objects, smaller size for distant than for near objects, diagonal placement, and converging lines, increases during middle childhood (Nicholls & Kennedy, 1992).

Realism in drawing appears gradually, with improvements in visual perception, fine-motor skills, symbolic understanding, and the working memory capacity needed to combine these components into a representation (Morra & Panesi, 2017; Riggs, Jolley, & Simpson, 2013; Toomela, 2002). Drawing of geometric objects follows the steps illustrated in Figure 8.7. (1) Three- to 7-year olds draw a single unit to stand for an object. To represent a cube, they draw a square; to represent a cylinder, they draw a circle, an oval, or a rectangle. (2) During the late preschool and school years, children represent salient object parts. They draw several squares to stand for a cube’s sides and draw two circles and some lines to represent a cylinder. However, the parts are not joined properly. (3) Older school-age children and adolescents integrate object parts into a realistic whole (Toomela, 1999).

Figure 8.7 Development of children’s drawings of geometric objects—a cube and a cylinder. As these examples show, drawings change from single units to representation of object parts. Then the parts are integrated into a realistic whole. (Based on Toomela, 2003.)

Cultural InfluencesWhy Are Children from Asian Cultures Advanced in Drawing Skills?

Observations of young children’s drawings in Asian cultures, such as China, Japan, Korea, the Philippines, Taiwan, and Vietnam, reveal skills that are remarkably advanced over those of their Western agemates. What explains such early artistic ability?

To answer this question, researchers examined cultural influences on children’s drawings, comparing China to the United States. Artistic models offered by the culture, teaching strategies, valuing of the visual arts, and expectations for children’s artistic development have a notable impact on the art that children produce.

In China’s 4,000-year-old artistic tradition, adults showed children how to draw, teaching the precise steps required to depict people, butterflies, fish, birds, and other images. When taught to paint, Chinese children follow prescribed brush strokes, at first copying their teacher’s model. To learn to write, they must concentrate hard on the unique details of each Chinese character—a requirement that likely enhances their drawing ability. Chinese parents and teachers believe that children can be creative only after they have acquired a foundation of artistic knowledge and technique (Golomb, 2004). To that end, China has devised a national art curriculum with standards and teaching materials extending from age 3 through secondary school.

The United States, as well, has a rich artistic tradition, but its styles and conventions are enormously diverse compared with those of Asian cultures. Children everywhere try to imitate the art around them as a way to acquire their culture’s “visual language.” But American children face a daunting imitative task, much like a child growing up in a context where each person speaks a different language (Cohn, 2014). Furthermore, U.S. art education emphasizes independence—finding one’s own style. American teachers typically assume that copying others’ drawings stifles creativity, so they discourage children from doing so (Copple & Bredekamp, 2009). Rather than promoting correct ways to draw, U.S. teachers, and parents as well, emphasize imagination and self-expression. While one American father and his 5-year-old daughter drew pictures side-by-side, he commented, “There aren’t any rules when you draw, so you can do it any way you want. That’s what’s fun about drawing.”

Does the Chinese method of teaching drawing skills beginning in the preschool years interfere with children’s creativity? To find out, researchers followed a group of Chinese-American children of immigrant parents and a group of European-American children, all from middle-SES two-parent families, from ages 5 to 9. At two-year intervals, the children’s human-figure drawings were rated for maturity and originality (inclusion of novel elements) (Huntsinger et al., 2011). On each occasion, the Chinese-American children’s drawings were judged more advanced and also more creative.

Interviews revealed that European-American parents more often provided their children with a rich variety of art materials, whereas Chinese-American parents more often enrolled their children in art lessons, viewing the development of artistic competence as more important. The Chinese-American children also spent more time as preschoolers and kindergartners in focused practice of fine-motor tasks, including drawing. And the more time they spent practicing, especially when their parents taught and modeled drawing at home, the more mature their drawing skills. At the same time, Chinese-American children’s artistic creativity flourished under this systematic approach to promoting artistic maturity. Once they succeeded at drawing basic forms, they spontaneously added unusual details of their own.

A 3-year-old in a Beijing preschool follows her teacher’s directions in an artistic exercise aimed at improving control of the crayon while experimenting with color combinations. Systematic teaching of artistic knowledge and technique combined with adult expectations that young children learn to draw well contributes to Chinese children’s advanced drawing skills.

© ELLEN B. SENISI

In sum, even though young Chinese children are taught how to draw, their artistic products are original. Once they succeed at drawing basic forms, they spontaneously add unusual details of their own. Although Western children may come up with rich ideas about what to draw, until they acquire the necessary skills, they cannot implement those ideas. Cross-cultural research indicates that children benefit from adult guidance in learning to draw, just as they do in learning to talk.

Cultural Variations in Development of Drawing

In cultures that have rich artistic traditions and that highly value artistic competence, children create elaborate drawings that reflect the conventions of their culture. Adults encourage young children by guiding them in mastering basic drawing skills, modeling ways to draw, and discussing their pictures. Peers, as well, talk about one another’s drawings and copy from one another’s work (Boyatzis, 2000; Braswell, 2006). All of these practices enhance young children’s drawing progress. And as the Cultural Influences box above reveals, they help explain why, from an early age, children in Asian cultures are advanced over Western children in drawing skills.

In cultures with little interest in art, even older children and adolescents produce only simple forms. In the Jimi Valley, a remote region of Papua New Guinea with no indigenous pictorial art, many children do not go to school and therefore have little opportunity to develop drawing skills. When a Western researcher asked nonschooled Jimi 10- to 15-year-olds to draw a human figure for the first time, most produced nonrepresentational scribbles and shapes or simple “stick” or “contour” images (see Figure 8.8) (Martlew & Connolly, 1996). These forms, which resemble those of preschoolers, seem to be a universal beginning in drawing. Once children realize that lines must evoke human features, they find solutions to figure drawing that vary somewhat from culture to culture but, overall, follow the sequence described earlier.

Figure 8.8 Human figure drawings produced by nonschooled 10- to 15-year-olds of the Jimi Valley of Papua New Guinea. Many produced (a) “stick” figures or (b) “contour” figures, which resemble the tadpole form of young preschoolers. (From M. Martlew & K. J. Connolly, 1996, “Human Figure Drawings by Schooled and Unschooled Children in Papua New Guinea,” Child Development, 67, pp. 2750–2751. © The Society for Research in Child Development. Adapted with permission of John Wiley and Sons, Inc., conveyed through Copyright Clearance Center, Inc.)

Early Printing

When preschoolers first try to write, they scribble, making no distinction between writing and drawing. As they experiment with lines and shapes, notice print in storybooks, and observe people writing, they attempt to print letters and, later, words. Around age 4, children’s writing shows some distinctive features of print, such as separate forms arranged in a line on the page. But children often include picturelike devices. For example, they might use a circular shape to write “sun.” Or they might call a large scribble the word lion, a small scribble the word caterpillar, and a red scribble the word apple (Ehri & Roberts, 2006; Levin & Bus, 2003). Applying their understanding of the symbolic function of drawings, 4-year-olds asked to write typically make a “drawing of print.” Only gradually, between ages 4 and 6, as they learn to name alphabet letters and link them with language sounds, do children realize that writing stands for language.

Preschoolers’ first attempts to print often involve their name, generally using a single letter. “How do you make a D?” my older son David asked at age 3½. When I printed a large uppercase D, he tried to copy. “D for David,” he proclaimed, quite satisfied with his backward, imperfect creation. A year later, David added several letters, and around age 5, he printed his name clearly enough that others could read it.

Between ages 3 and 5, children acquire skill in gripping a pencil. As Figure 8.9 shows, 3-year-olds display diverse grip patterns and pencil angles, varying their grip depending on the direction and location of the marks they want to make. By trying out different forms of pencil-holding, they discover the grip and angle that maximize stability and writing efficiency (Greer & Lockman, 1998). By age 5, most children use an adult grip pattern and a fairly constant pencil angle across a range of drawing and writing conditions.

Figure 8.9 Variations in 3-year-olds’ pencil grip. Through experimenting with different grips, preschoolers gradually discover an adult grip with one or two fingers on top of the pencil, which maximizes writing stability and efficiency. (Based on Greer & Lockman, 1998.)

Gains in fine-motor control and perception, along with experience with written materials, contribute to this 4-year-old’s emerging skill at gripping a marker and printing his name.

© LAURA DWIGHT PHOTOGRAPHY

In addition to gains in fine-motor control, advances in perception contribute to the ability to print. Like many children, David continued to reverse letters until well into second grade. Once preschoolers distinguish writing from nonwriting around age 4, they make progress in identifying individual letters. Many preschoolers confuse letter pairs that are alike in shape with subtle distinctive features, such as C and G, E and F, and M and W (Bornstein & Arterberry, 1999). Mirror-image letter pairs (b and d, p and q) are especially hard to discriminate. Until children start to read, they do not find it especially useful to notice the difference between these forms.

The ability to tune in to mirror images and to scan a printed line from left to right improves as children gain experience with written materials (Casey, 1986). Besides providing practice with a vital fine-motor skill, writing requires children to use their letter–sound knowledge to decide which marks, and in what order, to place on the page. The more parents and teachers assist preschoolers and kindergartners in their efforts to print, the more advanced children are in writing and other aspects of early literacy development. Furthermore, many studies confirm that being able to write letters and one’s own name by kindergarten predicts better reading and spelling achievement during the school years (Aram & Levin, 2011; Shanahan & Lonigan, 2010). We will consider early childhood literacy in greater detail in Chapter 9.

8.3.3 Individual Differences in Motor Skills

Wide individual differences exist in the ages at which children reach motor milestones. A tall, muscular child tends to move more quickly and to acquire certain gross-motor skills earlier than a short, stocky youngster. And as in other domains, parents and teachers probably provide more encouragement to children with genetically based motor-skill advantages.

Sex differences in motor development are already apparent in early childhood. Girls have an edge in skills that require balance and precision of movement, like jumping rope, but boys benefit from greater encouragement to improve their throwing, catching, and running skills.

Jose Luis Pelaez Inc/Getty Images

Sex differences in motor skills are evident in early childhood. Boys are ahead of girls in skills that emphasize force and power. By age 5, they can broad-jump slightly farther, run slightly faster, and throw a ball about 5 feet farther. Girls have an edge in fine-motor skills and in certain gross-motor skills that require a combination of good balance and foot movement, such as hopping and skipping (Fischman, Moore, & Steele, 1992; Haywood & Getchell, 2014). Boys’ greater muscle mass and, in the case of throwing, slightly longer forearms contribute to their skill advantages. And girls’ greater overall physical maturity may be partly responsible for their better balance and precision of movement.

From an early age, boys and girls are usually channeled into different physical activities. For example, fathers are more likely to play catch with their sons than with their daughters. Baseballs and footballs are purchased for boys, jump ropes and sewing materials for girls. Sex differences in motor skills increase with age, but they remain small throughout childhood (Greendorfer, Lewko, & Rosengren, 1996). This suggests that social pressures for boys to be active and physically skilled and for girls to play quietly at fine-motor activities exaggerate small genetically based sex differences.

8.3.4 Enhancing Early Childhood Motor Development

Many Western parents provide preschoolers with early training in gymnastics, tumbling, dance, soccer, and other movement skills through organized classes. These experiences can offer excellent opportunities for exercise and social interaction. But aside from throwing (where direct instruction is helpful), formal lessons during the preschool years have little added impact on gross-motor progress. Rather, children master the gross-motor skills of early childhood through everyday play.

When play spaces (left) are properly designed and equipped, young children respond eagerly to gross-motor challenges and develop new skills through informal play. Fine-motor skills benefit from environments richly stocked with puzzles, construction sets, and tools for sculpting, cutting, pasting, drawing, painting, and writing (above).

© ELLEN B. SENISI

© LAURA DWIGHT PHOTOGRAPHY

Nevertheless, the physical environment in which play takes place can affect mastery of complex motor skills. The Society of Health and Physical Educators (2009a) recommends that preschoolers engage in at least 60 minutes of adult-planned physical experiences in which parents and teachers provide enjoyable games and other playful activities, and up to several hours of child-directed physical activity, every day. When children have play spaces and equipment appropriate for running, climbing, jumping, and throwing and are encouraged to use them, they respond eagerly to these challenges. But if balls are too large and heavy to be properly grasped and thrown, or jungle gyms, ladders, and horizontal bars are suitable for only the largest and strongest children, then preschoolers cannot easily acquire new motor skills. Playgrounds must offer a range of equipment to meet the diverse needs of individual children.

Similarly, development of fine-motor skills can be supported through daily routines, such as dressing and pouring juice, and through richly equipped early childhood environments that include puzzles, construction sets, drawing, painting, sculpting, cutting, pasting, and writing. And as our discussion revealed, adults who guide and support children in drawing and writing foster not just their fine-motor mastery but their general artistic and literacy progress, respectively.

Finally, the social climate created by adults can enhance or dampen preschoolers’ motor development. When parents and teachers criticize a child’s performance, push specific motor skills, or promote a competitive attitude, they risk undermining children’s self-confidence and, in turn, their motor mastery (Berk, 2006). Adult involvement in young children’s motor activities should focus on fun rather than on winning or perfecting the “correct” technique.

Ask Yourself

Connect ■ How are experiences that best support preschoolers’ gross-motor development consistent with experience-expectant brain growth of the early years? (Return to page 163 in Chapter 5 to review.)

Apply ■ Mabel and Chad want to do everything they can to support their 3-year-old daughter’s motor development. What advice would you give them?

Reflect ■ Do you think that American children should be provided with systematic instruction in drawing skills beginning in early childhood, similar to the direct teaching Chinese children receive? Explain.

Summary

8.1 A Changing Body and Brain (p. 281)

8.1 Describe body growth and brain development in early childhood.

Gains in body size taper off in early childhood as children become longer and leaner, and individual differences in body size and rate of growth become more apparent.

New epiphyses emerge in the skeleton, and by the end of the preschool years, children start to lose their primary teeth. Care of primary teeth is essential because diseased baby teeth can affect the health of permanent teeth. Childhood tooth decay is common, especially among low-SES children.

By age 4 to 5, many parts of the cerebral cortex have overproduced synapses, and synaptic pruning occurs. To make room for the connective structures of stimulated neurons, many surrounding neurons die, leading to reduced brain plasticity.

Prefrontal-cortical areas devoted to various aspects of executive function develop rapidly from early to middle childhood. For most children, the left cerebral hemisphere is especially active, supporting rapidly expanding language skills.

Changes in other areas of the brain involve establishing links between brain structures. Fibers linking the cerebellum to the cerebral cortex grow and myelinate, enhancing motor coordination and cognition. Also developing rapidly are the reticular formation, responsible for alertness and consciousness; the hippocampus, which plays a vital role in memory and understanding of space; the amygdala, which plays a central role in processing novelty and emotional information; and the corpus callosum, which connects the two cortical hemispheres.

Persistent childhood poverty can compromise brain structures crucial for learning, thereby contributing to the lower cognitive scores of poverty-stricken children relative to their financially better-off agemates.

8.2 Influences on Physical Growth and Health (p. 285)

8.2a Describe the effects of heredity, restful sleep, nutrition, and infectious disease on physical growth and health in early childhood.

Genes influence physical growth by controlling production and release of two vital hormones from the pituitary gland: growth hormone (GH), which affects the development of almost all body tissues, and thyroid-stimulating hormone (TSH), which affects brain growth and body size.

Because GH is released during the child’s sleeping hours, sleep contributes to body growth. Sleep difficulties are associated with impaired cognitive functioning and emotional adjustment, especially for low-SES children. Total sleep declines in early childhood, but with substantial individual variability.

Sleep problems frequently stem from inadequate parental control over young children’s use of screen media, as well as a mismatch between parental demands and children’s sleep needs. Many preschoolers have difficulty falling asleep, and most waken occasionally at night. A few suffer from sleep disorders, such as sleep-walking or sleep terrors, which run in families, suggesting a genetic influence. These problems can also be triggered by stress or extreme fatigue. Most subside with age.

As growth rate slows, preschoolers’ appetites decline, and they often become wary of new foods. Providing preschoolers unpressured opportunities to taste new foods can promote healthy, varied eating. In contrast, excessive parental control over children’s food intake interferes with children’s responsiveness to hunger cues and can lead to eating problems.

Dietary deficiencies are associated with attention and memory difficulties, academic and behavior problems, and greater susceptibility to infectious diseases. Diseases also contribute to malnutrition, especially those that cause persistent diarrhea. In developing countries, inexpensive oral rehydration therapy (ORT) and zinc supplements can prevent most developmental impairments and deaths due to diarrhea.

Immunization rates are lower in the United States than in other industrialized nations because many low-income children lack access to adequate health care. Parental stress and misconceptions about vaccine safety also contribute.

Child-care attendance increases the risk of exposure to infectious diseases. Because repeated bouts of otitis media can disrupt language development and later academic performance, early prevention is important.

8.2b Cite factors that increase the risk of unintentional injuries, and explain how childhood injuries can be prevented.

Unintentional injuries are the leading cause of childhood mortality in industrialized nations. Injury victims are more likely to be boys; to be temperamentally irritable, inattentive, overactive, and aggressive; and to live in stressed, poverty-stricken, crowded family environments.

Effective injury prevention includes passing laws that promote child safety; creating safer home, travel, and play environments; relieving sources of family stress; and changing parent and child behaviors.

8.3 Motor Development (p. 296)

8.3a Cite major milestones of gross- and fine-motor development in early childhood.

As preschoolers’ center of gravity shifts toward the trunk, balance improves and gaits become smooth and rhythmic, paving the way for such new gross-motor achievements as running, jumping, hopping, galloping, skipping, and throwing and catching.

Increasing control of the hands and fingers leads to dramatic improvements in fine-motor skills. Preschoolers gradually become adept at self-help skills such as dressing themselves and using a fork and knife.

As perceptual, cognitive, and fine-motor capacities improve, children’s drawings progress from 1- to 2-year-olds’ scribbles to 3- and 4-year-olds’ representational forms and 5- and 6-year-olds’ more realistic drawings.

Children’s artistic traditions also influence their drawings. In Asian cultures, early teaching of how to draw produces results that are remarkably advanced without dampening children’s creativity.

Between 3 and 5 years, children experiment with pencil grip; by age 5, most use an adult-like grip that maximizes stability and writing efficiency.

Improved perception and exposure to written materials contribute to progress in discriminating and accurately printing individual letters. When parents and teachers support children’s efforts to print, preschoolers are more advanced in writing and other aspects of literacy development. The ability to write letters and one’s own name by kindergarten predicts better reading and spelling achievement during the school years.

8.3b Describe individual differences in preschoolers’ motor skills and ways to enhance motor development in early childhood.

Body build and opportunity for physical play affect early childhood motor development. Sex differences that favor boys in skills requiring force and power and girls in skills requiring good balance and fine movements are partly genetic, but social pressures exaggerate them.

Children master the motor skills of early childhood through informal play experiences, with little benefit from exposure to formal training. Motor development during the preschool years is best promoted through richly equipped play environments that offer pleasurable physical activities and accommodate a wide range of abilities.

IMPORTANT TERMS AND CONCEPTS

amygdala (p. 285)

cerebellum (p. 284)

corpus callosum (p. 285)

growth hormone (GH) (p. 287)

hippocampus (p. 284)

pituitary gland (p. 286)

reticular formation (p. 284)

thyroid-stimulating hormone (TSH) (p. 287)

Descriptions of Images and Figures

Back to Figure

Wilson at 3 years is pushing a toy lawnmower. Wilson at 3 and a half years is about to go down a slide. Wilson at 4 and a half years is taller and standing outside. Wilson at 5 years is wearing a helmet and riding a bike. Mariel at 2 and a half years is wearing only a diaper and playing with a hose outside. Mariel at 4 years is taller and playing on a playground. Mariel at 4 and a half years is swinging from a bar on a playground. Mariel at 5 years is standing in the opening of a tent.

Back to Figure

The bottom of the brain is labeled reticular formation. This is just in front of the cerebellum, behind the pituitary gland, which is just below the amygdala, next to the hippocampus, which is surrounded by the corpus callosum.

Back to Figure

The graph shows the mean sleep disturbances score by the daily hours devoted to screen media. The data is as follows:

0 to 2 hours: 11.5

2.1 to 4 hours: 11.3

4.1 to 6 hours: 11.7

6.1 to 8 hours: 12.5

8.1 to 10 hours: 13.6

Greater than 10 hours: 12.8

All values are estimated.

Back to Figure

The graph shows the odds of weight category by weight category for 2 groups, maternal pressure and maternal restriction. The data is as follows.

Underweight. Pressure: 1.3. Restriction: 0.85.

Overweight. Pressure: 0.65. Restriction: 1.2.

Obese. Pressure: 0.55. Restriction: 1.45.

All values are estimated.

Back to Figure

The preschooler pulls the arm straight up and a little back and then pushes it forward. The older child pulls the arm back, then up, then around, finally throwing the ball.

Back to Figure

At age 3 to 7 years, the drawing category is single units and the cube and cylinder look very similar, with the cylinder just slightly thinner and taller. At age 4 to 13 years, the category is object parts, and the drawings show the straight lines on the cube and curved parts of the cylinder more clearly, with lines and faces drawn in rudimentarily. At age 8 years and older, the category is integrated whole, and the drawings show both cube and cylinder in a realistic 3D way.

Back to Figure

The grips are as follows.

Both hands clenched in fists.

Correct finger grips but hand and pencil are upside down.

Held like a sword.

Held like a sword with thumb and pointer finger extended.

Clenched in 1 fist.

Held almost correctly, but more like a pinch.

Clenched in a first, with the pencil poking through between the third and fourth fingers.

Clenched in a fist in the other hand.

Held in a pinch about halfway up the pencil.

Gripped with all 5 fingertips.

The last 2 images show 2 correct adult grips.