Child and Ad Psych - Chapter 5 - Biosocial Development First 2 years

Body Changes

• an average newborn is 7 ½ lbs, 20 inches

• infants triple their birthweight by one year

• by age 2, they are about ½ of their adult heigh and ¼ their adult weight

Head sparing

in cases of inadequate nutrition, the brain keeps growing

Infant Sleep

• newborns spend 15 - 17 hours a day sleeping

• 80% of 1 year olds sleep “through the night”

• sleep cycles are influenced by brain maturation, diet, child-rearing practices, and birth order

Co-sleeping

• CULTURE influences the decisions ( it is more common in eastern culture)

• it is NOT harmful to an infant, under normal circumstances ( if adult is not drunk)

• It may increase dependence on parents

Brain development

• by the age of 2, the brain is 75% its adult weight

• neural connections is the brain also develops

Regional Specialization

• neurons in certain areas of the brain correspond to different tasks

• Examples: language, vision, smell, emotional processing, recognizing faces vs objects)

Frontal cortex

• the front part of the cortex assists in planning, self-control and self-regulation.

• it is very immature in the newborn

Visual cortex

• vision is the least mature sense at birth because the fetus has nothing to see while in the womb

Transient exuberance

• rapid proliferation of new neural connections in infancy

  • estimated fivefold increase in number of dendrites in the cortext occurs in first 2 years

  • as many as 15,000 new connections pere neuron and 100 trillion synapses by age 2

Experience-expectant

• Brain functions require basic common experiences

  • Example: no matter where an infant ives, he or she hears sounds and language

experience - dependent

• brain functions depend on exposure to particular events

  • Example: the particular sounds and language heard ( and learned) varies across infants

  • Example: the development of impulse control depends on both maturation and practice

Infant senses

• all five sense function at birth ( vision, hearing, taste, touch, smell)

• Perception: the brains processing of the sensation develops over time

Hearing

• well developed as birth

  • Infants respond to sudden noises, human voice, phonemes of language

VIsion

• is the least mature sense at birth

  • Binocular vision develops around 14 weeks

  • “adult” 20/20 vision by one year

Motor skills

• develop in two ways

  • Cephalocaudal: growth proceeds from head to toe

  • Proximal-distal: growth proceeds from the torso outward

• Reflexes account for the first motor skills

• Survival reflexes: include sucking, breathing, body temperature

Gross Motor Skills

involve large muscle movements

Examples: crawling, sitting, walking

• walking typically occurs around 12 months, with great variability across infants

• walking requires muscle strength, brain maturation, and practice

Fine motor skills

involve small muscle movements

Examples: learning to grasp, shake, pull an object, hold a spoon, write, draw

Motor skills are influenced by genes, culture, and patterns of infant care

Sudden Infant Death Syndrome

• SIDS is infant death of unknown causes

• Babies between 2-6 months suddenly stop breathing and die in their sleep

• Susan Beal, came through with a breakthrough identify that almost all of the babies of European desent died while they were sleeping on their stomaches

Amygdala

registers emotions ( positive and negative, especially fear )

Hippocampus

Central processor of memory, especially memory for locations

Hypothalamus

responds to signals from the amygdala and to memories from the hippocampus by producing hormones, especially CORITSOL

Pituitary

responds to the hypothalamus by sending our hormones to various body parts