Human Growth and
Development
Chapter Eight The Play Years:
Biosocial DevelopmentPowerPoints prepared by Cathie Robertson, Grossmont CollegeRevised by Jenni Fauchier, Metropolitan Community College
Body and Brain
•Young children’s body and brain develop according to powerful epigenetic forces–Biologically driven–Socially guided
• Lower body lengthens– child becomes slimmer
• Steady increase in height and weight– 3 inches in height per year– 4 1/2 pounds in weight per year
Body Shape and Growth Rates
• Genetic background prepares child to be experience-expectant
• Cultural patterns and differences guide development
• Most influential factors– genes, health, nutrition
• Other influencing factors– sex, birth order, geography
Genes and Ethnic and Cultural Differences
Eating Habits
• Food should be nutritious– isn’t always—often far from “ideal”– enough calories—not enough vitamins
and minerals—major nutritional problems are•iron-deficiency anemia•too much sugar•too much fat•not enough fruits and vegetables
• Underlies rapidly expanding cognitive abilities– by age 2, 75% of brain weight
achieved– by age 5, 90% of brain weight
achieved– pruning of dendrites has occurred
Brain Development
• Myelination—process by which axons become insulated with a coating of myelin, a fatty substance that speeds transmission of nerve impulses– thoughts follow each other fast enough
for children to perform one task after another
– fast processing essential for fast and complex communication
– experience affects rate of myelination
Speed of Thought
• Corpus callosum—nerve fibers that connect the two halves of the brain
Connecting the Brain’s Hemispheres
• Left Side, Right Side– lateralization—specialization of the
two sides of the brain•left brain
– logical analysis, language, speech
•right brain–visual and artistic skills
• Coping with Brain Damage
Connecting the Brain’s Hemispheres, cont.
• Prefrontal cortex (or frontal lobe) is the final part of the human brain to reach maturity– the area in the very front of the brain that
is least developed in nonhumans– mid-adolescence
•maturation occurs gradually and incomplete until advances at about age 3 or 4 make possible impulse control and formal education
Planning and Analyzing
• Perseveration—the tendency to persevere, to stick to a thought or action long after it is time to move on– occurs normally in young
children—another aspect of immature self- control
Planning and Analyzing, cont.
• By age 6, children are ready for formal instruction– before, brain not sufficiently developed in
ways it needs to be, but now child can• sit still for more than an hour• scan a page of print• balance sides of body• draw and write with one hand• listen and think before talking• remember important facts• control emotions
Educational Implications of Brain Development
• The brain provides the foundation for education– any impediments to normal growth
of the brain can put academic achievement on shaky ground
Educational Implications of Brain Development, cont.
• Brain development allows for greater coordination and impulse control
• Physical maturation can make a child more vulnerable to injury
Motor Skills and Avoidable Injuries
Gross Motor Skills
• Large body movements improve– running, jumping, climbing,
throwing• Gross motor skills are practiced
and mastered
Gross Motor Skills, cont.
• Motor skills develop as rapidly as brain maturation, motivation, guided practice, and innate ability allow
• Children learn basic motor skills by teaching themselves and learning from other children
• Small body movements are harder to master– pouring, cutting, holding crayon, tying– lacking the muscular control, patience,
and judgment needed•fingers short and fat •confusion over which is dominant hand
Fine Motor Skills
Artistic Expression• Children’s artistic endeavors are also their
play– drawings often connected to perception
and cognition•gradual maturation of brain and body is apparent
– artwork helps develop fine motor skills– in artwork, many children eagerly
practice perseveration
Serious Injuries
• Accidents are the most common cause of childhood death– poison, fire, falls, choking, and drowning– unintended injuries cause millions of
premature deaths per year until the age of 40; then disease becomes greatest cause of mortality
• Injury control/harm reduction—the idea that accidents are not random, but can be made less harmful with proper control
• Primary prevention—actions that change overall background conditions to prevent some unwanted event or circumstance
• Secondary prevention—actions that avert harm in the immediate situation
• Tertiary prevention—actions taken after an adverse event to reduce the harm or prevent disability
3 Levels of Prevention
• An Example: Pedestrian Deaths– Primary prevention: Better sidewalks, slower
speeds, wider roads, longer traffic signals, etc.– Secondary prevention: Improving car brakes,
having school-crossing guards, having children walk with adults, etc.
– Tertiary prevention: Protective helmets, laws against hit-and-run driving, emergency room procedures, etc.
Three Levels of Prevention, cont.
• SES is a powerful predictor of many accidents
• Prevention and protection crucial • Parents need to institute safety
measures in advance– Parents’ job is protection
Parents, Education, and Protection
•Sensational cases attract attention- but don’t represent the typical case- still, we need to learn lessons about abuse in order to understand its causes and consequences
Child Maltreatment
• Abuse and neglect– child maltreatment—intentional
harm or avoidable endangerment to child
– child abuse—deliberate action that is harmful to child’s well-being
– child neglect—failure to meet child’s basic needs
Changing Definitions of Maltreatment
• Types of abuse: physical, sexual, emotional, and educational
• Neglect twice as common as abuse– one sign is failure to thrive– another is hypervigilance
•can be a symptom of post-traumatic stress disorder
Changing Definitions of Maltreatment, cont.
• Reported maltreatment—cases about which authorities have been informed
-3 million per year• Substantiated maltreatment—cases
that have been investigated and verified
-1 million per year
Changing Definitions of Maltreatment, cont.
Consequences of Maltreatment
• If not spotted early, then reported and stopped, maltreatment can affect every aspect of a child’s development
Brain Damage and Consequences for
Learning• Types of possible brain damage
– shaken baby syndrome•condition caused by maltreatment
involving shaking a crying baby, with severe brain damage as result
– brain damage in despondent or terrorized child•memory may be impaired; logical
thinking may be delayed
•Another brain disorder may appear in neglected child with clinically depressed mother unable to provide emotional support and guidance- right prefrontal cortex develops more than left; consequently, negative emotions dominate, with greater likelihood of depression occurring
• Inadequate essential nourishment also impedes normal brain development
Impaired Social Skills
• Maltreated children’s social skills– less friendly, more isolated and
aggressive– the earlier abuse begins, the
worse the relationship with peers
Three Levels of Prevention, Again
• Primary prevention—prevents maltreatment before problem starts– need for family support, e.g.,
•stable neighborhoods•basic values•SES
• Secondary prevention—responds to first symptoms or signs of risk- spots and treats early problems
•identifies high-risk children- potential disadvantages
•wrongfully stigmatizes family as inadequate
•undermines helpful cultural or family patterns
•creates sense of helplessness in families