The Developing Person Through the Life Span 8e by Kathleen Stassen Berger Chapter 5- The First Two Years: Biosocial Development PowerPoint Slidesdeveloped by Martin Wolfger and Michael James Ivy Tech Community College-Bloomington Reviewed by Raquel Henry Lone Star College, Kingwood
Body Changes Body Size • Average weight: double the birthweight by month 4, triple it by age 1, much of it is fat • Average height: grow 14 inches from birth to age 2 These numbers are norms, an average measurement.
Body Changes Body Size • Head-sparing- biological mechanism that protects the brain when malnutrition disrupts body growth. • The brain is the last part of the body to be damaged by malnutrition. • Percentile- point on a ranking scale of 0 to 100. • 50th percentile is the midpoint with ½ the sample being higher and ½ lower.
Sleep • Average newborn sleeps 16 hours per day • Specifics vary due to age, characteristics, and social environment • Ample sleep correlates with normal brain maturation, learning, emotional regulation, academic success and psychological adjustment
Sleep • REM Sleep: Rapid eye movement sleep, dreaming, rapid brain waves • Slow-wave sleep: quiet sleep, increases at 3-4 months • Co-sleeping: custom of parents and children sleeping in same room, more common in Asia, Africa and Latin America than in Western cultures
Brain Development • Neuron- the billions of nerve cells in the central nervous system. • Cortex- the outer layers of the brain. • Axon-a fiber that extends from a neuron and transmits electrochemical impulses from that neuron to the dendrites of other neurons.
Brain Development • Dendrite-a fiber that extends from a neuron and receives electrochemical impulses transmitted from other neurons via their axons. • Synapse-the intersection between the axon of one neuron and the dendrites of other neurons. • Neurotransmitter-a brain chemical that carries information from the axon of a sending neuron to the dendrites of a receiving neuron.
Transient Exuberance • The great but temporary increase in the number of dendrites in an infant’s brain from birth to age 2 • Enables neurons to connect and communicate with other neurons • This is followed by pruning where unused neurons and misconnected dendrites die
Stress and the Brain • If it produces too many stress hormones in infants, the brain will not be able to have normal stress responses. • Occurs in infants who are terrified and experience other forms of stress. • Can continue to occur when the infant is an adult
Necessary and Possible Experiences Experience-related aspects of brain function: • Experience-expectant : require basic common experiences in to develop normally (i.e. people who love them) • Experience-dependent: these happen to some infants but not all, not necessary for brain function (i.e. language baby hears)
Brain Development • prefrontal cortex: the area for anticipation, planning, and impulse control • Shaken baby syndrome- a life-threatening injury occurring when an infant is forcefully shaken back and forth, rupturing blood vessels and breaking neural connections . • Self-righting- inborn drive to fix a developmental deficit • All people have self-righting impulses for physical and emotional imbalances.
Sensation and Movement • Sensation- The response of a sensory system (eyes, ears, skin, tongue, nose) when it detects a stimulus. • Perception- The mental processing of sensory information when the brain interprets a sensation. • Sensory development- typically precedes intellectual and motor development
Sensation and Movement Hearing develops during the last trimester of pregnancy and is already quite acute at birth; the most advanced of the newborn’s senses. Vision is the least mature sense at birth. • Newborns focus only on objects between 4 and 30 inches away. • Binocular vision, the ability to coordinate the two eyes to see one image, appears at 3 months.
Smelling, Tasting, and Touching • Function at birth and adapt to social world • Babies recognize each person’s smell and handling • Basic Infant Care differs by culture • Massage important in some cultures • Infant senses function to help babies join the human family
Sensation and Movement • Gross motor skills- Physical abilities involving large body movements, such as walking and jumping. • Fine motor skills- Physical abilities involving small body movements, especially of the hands and fingers, such as drawing and picking up a coin.
Ethnic Variations • Gene differences in different ethnic groups • Cultural patterns of child rearing affect sensation, perception, and motor skills
Surviving in Good Health • About 10 billion babies were born 1950-2010 worldwide • More than 2 billion died before age 5 • Immunization has saved many people • The risks of diseases are far greater than the risk from immunization.
Surviving in Good Health Nutrition • For every infant disease (including SIDS), breast-feeding reduces risk and malnutrition increases it. • Breastfed babies are less likely to develop allergies, asthma, obesity, and heart disease. • As the infant gets older, the composition of breast milk adjusts to the baby’s changing nutritional needs.
Malnutrition • Protein-calorie: when not enough food of any kind is consumed • Stunting: being too short for your age due to severe and chronic malnutrition • Wasting: being very underweight due to malnutrition
Malnutrition • Marasmus: severe malnutrition during infancy where child stops growing, tissues waste away and then usually dies • Kwashiorkor: disease of chronic malnutrition during childhood where child becomes more likely to get other diseases such as measles, diarrhea and influenza