DEVELOPMENTAL PSYCHOLOGY

PRENATAL DEVELOPMENT “Before birth”

CONCEPTION Sperm meets egg – “fertilization” Fertilized eggs are zygotes *no examples needed for these terms: zygote, embryo, fetus

GROWTH Zygotes add 100 cells in first week and cells differentiate (how does that happen?!?) 10 days – zygote attaches to wall of uterus, inner cells become embryo, outer cells become placenta (sac of nutrients that connects mother to embryo)

9 weeks – embryo looks human, called “fetus” Pregnancy typically lasts 37 weeks

THINGS FETUSES CAN DO 7.5 weeks – reflex to move head away from stimulation at mouth 15 weeks – reflex to close hand when palm is touched, fetus can grasp, frown, squint, swallow, and suck its thumb 24 weeks – fetus may respond to sounds 27 weeks – responds to light shone on mothers’ abdomen, responds to touch 32 weeks – brain circuits are virtually identical to newborns. The fetus experiences deep sleep 35 weeks- hearing is mature Birth – baby can see shapes and colors within 13 inches of its face, distinguish volume, pitch, and tone, and may show a preference for sweet tastes and mother’s scent

TERATOGENS: THINGS THAT NEGATIVELY AFFECT FETAL DEVELOPMENT Viruses (HIV, etc) Drugs (babies can be born with an addiction) Alcohol – no amount is known to be safe  Children may be born with a predisposition to like alcohol  Fetal Alcohol Syndrome results from heavy drinking and causes a smaller-than-proportional head and brain abnormalities

INFANTS

NEWBORNS CAN Cry Suck Turn their heads Root (find a nipple) Babinski reflex- toes flare out and curl back in when bottom of foot is touched

NEWBORNS CAN CONT. Moro reflex- arms thrust out and back arches in response to surprise or sudden noise Plantar reflex – toes curl in when ball of foot is touched Swimming reflex – if briefly submerged in water, babies hold their breath and pump arms and legs Stepping reflex – infants move feet up and down when held over a surface

BRAIN DEVELOPMENT Infants are born with their lifetime supply of brain cells Connections between neurons become more complex with time and experience Motor, speech, and memory areas develop first, followed by frontal lobes and association areas Pathways grow until puberty, at which point they are “pruned” – extras destroyed, important ones strengthened

MOTOR DEVELOPMENT All infants go through stages in the same order but at varying ages  Roll over  Sit up unsupported  Crawl  Walk  Run

AT WHAT AGE DO YOU THINK INFANTS…  Laugh  Sit without support  Walk unassisted  Feel shame  Recognize and smile at parents  Kick a ball forward  Make two-word sentences  Think about things that cannot be seen 2 months 5-6 months 12 months 2 years 4-5 months 20 months months 2 years

INFANTS AND MEMORY Psychologists use infants’ habituation to stimuli to measure their interest, perception, and memory Infants can learn and remember basic actions beginning at 2 months Conscious memory for events begins around age 3.5

COGNITIVE DEVELOPMENT Mostly Piaget

JEAN PIAGET AND SCHEMAS Piaget realized that children think and reason differently than adults do Believed our brains make schemas (concepts) into which we fit our experiences We assimilate experiences into schemas (make the world fit what we know) We accommodate our schemas to add new experiences (adjust schemas to fit the world)

PIAGET’S STAGES OF DEVELOPMENT See pages (we did an activity in class) Also check out these videos of children in each stage of development passing and failing tests of object permanence, egocentrism, conservation, and more. 8VGB9yq-f 8VGB9yq-f