Ch9

• Middle and late childhood

  Period of slow, consistent growth before the rapid growth spurt of adolescence
• During the elementary school years, children grow an average of 2 to 3 inches a year
• At the age of 11, the average girl is 4 feet, 10 inches tall, and the average boy is 4 feet, 9 inches tall
• During middle and late childhood, children gain about 5 to 7 pounds a year
• Proportional changes in middle and late childhood

  • Head circumference and waist circumference decrease in relation to body height
  • Bones continue to ossify but yield to pressure and pull more than mature bones
• Brain-imaging techniques


  Magnetic resonance imaging (MRI)
• Total brain volume stabilizes by the end of late childhood, but significant changes in various structures and regions of the brain continue to occur
• Development of the prefrontal cortex

  • Linked to children's improved attention, reasoning, and cognitive control
  • Likely orchestrates the functions of many other brain regions during development
  • Provides an advantage to neural networks and connections that include the prefrontal cortex
  • Coordinates the best neural connections for solving a problem at hand
  • Emerging cognitive control during childhood is mainly supported by the development of distributed neural networks in which the prefrontal cortex is central
• Cortical thickening across a two-year time period was observed in the temporal and frontal lobe areas that function in language, which may reflect improvements in language abilities such as reading
• Children with a high body mass index had less cortical thickness, which was linked to a lower level of executive function
• Brain activation shifts


  1. From diffuse, larger areas to more focal, smaller areas

  2. Characterized by synaptic pruning, a process in which areas of the brain that are not being used lose synaptic connections while areas that are used gain increased connections
• Increased connectivity between brain regions also occurs as children develop
• Connectivity between the prefrontal and parietal lobes in childhood was linked to better reasoning ability later in development
• Motor skills in middle and late childhood

  • Become much smoother and more coordinated than in early childhood
  • Boys usually outperform girls in gross motor skills involving large muscle activity
  • Girls usually outperform boys in their use of fine motor skills
• Myelination of the central nervous system


  Reflected in the improvement of fine motor skills during middle and late childhood
• Fine motor skills in middle and late childhood

  • Hammering, pasting, tying shoes, fastening clothes
  • Printing becomes smaller and more even
  • Cursive letter size becomes smaller and more even
  • Mastering complex, intricate, and rapid movements needed to produce fine-quality crafts or to play a difficult piece on a musical instrument
• America's children are not getting enough exercise
• Factors associated with children's greater physical activity

  • Parents' encouragement of physical activity
  • Parents' support of physical activity
  • Time children spent outdoors
  • Children's sports participation
  • Having a number of physical activity facilities near their home
• Engaging in regular exercise was linked to lower rates of internalizing and externalizing problems in children
• Benefits of aerobic exercise for children

  • Reduction of body fat
  • Lower fasting insulin
  • Decreased inflammatory markers
  • Increased physical fitness
  • Improved processing speed, attention, memory, effortful and goal-directed thinking and behavior, and creativity
  • Improvements in children's attention, executive function, and academic achievement
• Prolonged exercise interventions with 6- to 12-year-olds that consisted of multiple exercise activities per week for more than 6 weeks improved the children's executive function in general and their inhibitory control in particular
• Physical activity interventions improved the cognitive performance (especially executive function) of overweight or obese children
• Cardiorespiratory fitness was linked to improved attentional skills, including concentration, and psychological well-being in fourth-graders
• Roles of parents and schools in determining children's exercise levels

  • Growing up with parents who exercise regularly provides positive models of exercise for children
  • School-based physical activity interventions can increase children's self-reported psychological well-being and relations with peers
• Heavy engagement in screen time

  Linked with inactivity, obesity, and worse sleep patterns in children
• Excessive screen time was associated with lower connectivity between brain regions, as well as lower levels of language skills and cognitive control in 8- to 12-year-olds
• Ways to encourage children to exercise more

  • Offer more physical activity programs run by volunteers at school facilities
  • Improve physical fitness activities in schools
  • Have children plan community and school activities that interest them
  • Encourage families to focus more on physical activity, and encourage parents to exercise more
• Middle and late childhood is a time of excellent health, with disease and death less prevalent than during other periods in childhood or adolescence
• Health disparities in children living in poverty and children of color

  • A higher proportion of children in some ethnic minority groups, especially Black American and Latino children, live in families with incomes less than 200 percent of the federal poverty level
  • Children from some ethnic minority groups have a higher prevalence of obesity, asthma, type 2 diabetes, and hypertension
  • Such health disparities are due to underlying medical problems, the occupations/employment of their caregivers, discrimination and racism, and limited access to care
  • In 2019, 7.2 percent of Latino children were uninsured, compared with 5.1 percent of non-Latino White children
• The COVID-19 pandemic has disproportionately affected children living in poverty and children of color, as well as children who are vulnerable due to their living situations or underlying health conditions
• Accidents and injuries in middle and late childhood

  • Injuries are the leading cause of death, with the most common cause being motor vehicle accidents
  • Safety-belt restraints and child booster seats can greatly reduce the severity of motor vehicle injuries
• Overweight


  Defined in terms of body mass index (BMI), with children at or above the 97th percentile included in the obesity category, at or above the 95th percentile in the overweight category, and at or above the 85th percentile described as at risk for being overweight
• In 2018, 20.3 percent of 6- to 11-year-old U.S. children were overweight
• In a recent study, the greatest increase in being overweight occurred in 5- to 11-year-old children, from 36.2 percent in March 2019–January 2020 to 45.7 percent in March 2020–January 2021
• Causes of children being overweight

  • Heredity is an important factor, with overweight parents tending to have overweight children
  • Environmental factors include availability of food (especially high in fat), use of energy-saving devices, declining physical activity, parents' eating habits and monitoring of children's eating habits, the context in which a child eats, and heavy screen time
• Consequences of being overweight

  • Increased risk for diabetes, hypertension, elevated blood cholesterol levels, and sleep problems
  • Increased likelihood of depression and anxiety symptoms
  • Link with low self-esteem
• Consequences of being overweight

  • Raises the risk for many medical and psychological problems
  • Includes diabetes, hypertension, elevated blood cholesterol levels, and sleep problems
• Obese children were more than twice as likely to have hypertension as normal-weight children in a recent large-scale Chinese study
• Children and adolescents who were obese were more likely to have depression and anxiety symptoms than non-obese children and adolescents in another Chinese study
• Obesity is linked with low self-esteem in children according to a research review