Developmental Psychology

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

NewBornsCAn • 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 • 20-22 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 417-426 (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. https://www.youtube.com/watch?v=NjBh9ld_yIo&list=PLNg03A2sfuveXHjjFiD4XLQD8VGB9yq-f

Developmental Psychology