PSYA02 Lecture 2 Notes PDF

Class 2 - Human Development Part 1 January 10, 2025 Prenatal and Infant Development Human Development The examination of continuity and change across the lifespan (the amount of change happen during the child's development, which is why most developmental psychologists work with young...

Class 2 - Human Development Part 1 January 10, 2025 Prenatal and Infant Development Human Development The examination of continuity and change across the lifespan (the amount of change happen during the child's development, which is why most developmental psychologists work with younger children) - Continuity: what stays the same in humans (ex: personality) - Change: either gradual or abrupt change (ex: ability to walk) Variety of topics of continuity and change - Sensation and perception (detecting the environment and organizing that information) - Cognition and language (ability to think and express with words) - Emotion (ability to control and express feelings) - Social and moral behaviors (how to behave in society) Four main periods of human development 1. Prenatal period and infancy (conception - 2~3 years) 2. Childhood (2~3 - 11 years) 3. Adolescence (12 - ?? Years) --> when the brain stops maturing, mostly 25 years 4. Adulthood (?? - death) *the numbers are approximate since individuals go through development at different times Warm-Up Think about your earliest memory, how old were you? - Most frequent years: 3 to 4 years when the memories are forming - Types of first memory: painful experience, emotional discomfort, high sensation - Our early memories are often vague or non-existent --> Failure of autobiographical memory, can lead us to believe that experiences as young infants New Section 1 Page 1 --> Failure of autobiographical memory, can lead us to believe that experiences as young infants are less relevant…which is not true! Early Experience in Infancy Experience in infancy is crucial to normal development, such as language exposure, food, music, etc Give rise to many of individual differences across the human population Early Experience In utero experience - Sounds: happens during pregnancy, the rhythm of the speech - Tactile sensation: detecting movement of the mother and moving - Tastes and smells: chemical markers in the tongue, what mother eats (ex: preference to ginger when mother eats lots of ginger), having preference with smells Prenatal Development Begins with conception 1. Germinal (0~3 weeks): zygote *after implantation, germinal is considered to end 2. Embryonic (3~8 weeks): organ development 3. Fetal (9 weeks~birth): growth and maturation of the system Developmental Process in Brain Development 1. Neurogenesis: creation of neurons 2. Myelination: makes the neural process smoother 3. Synaptogenesis: formation of the synaptic cleft, connections between neurons 4. Synaptic pruning: cutting off the connections --> when the connections are not used, they can be reallocated (ex: children learn more easily than adults, if the connections are not used, information disappears) Fetal Experience and Sensation New Section 1 Page 2  Uterus is not a vacuum, fetuses experience stimuli in utero (check Early Experience slide again) Fetal Audition (hearing) Fetal heartbeat changes in reaction to external voices being played (ex: calm environment, heartbeat goes up / loud environment, heartbeat goes down) Fetal heartbeat is different in reaction to music than it is to human speech Newborn babies recognize their mother's language and their mother's voice Opal is pregnant with her second child. The developing baby ahs begun to hear sounds from the outside world, learning about he mother's native language and the types of music that her mother listens to. In what stage prenatal development in Opal's baby? a) germinal stage (too early) b) embryonic stage (too early) c) fetal stage d) learning stage (distraction) e) perceptual stage (distraction) *this type of practice question is similar to the test question Teratogens External substances that negatively affect the fetus's development (ex: alcohol, medication, radiation, recreational drug, virus, smoke; second-hand smoking, viruses, high dose of caffeine, etc) Can cause fetal abnormalities or even death, most affect fetuses during critical and sensitive periods - Critical period: when the most change is happening in a particular structure, very severe (ex: development of heart during embryonic stage) - Sensitive period: development is still happening but less severe Yolanda is pregnant with her first child. Unfortunately, she integrated teratogens that resulted in abnormalities in her child's heart. At approximately how many weeks prenatal age is Yolanda likely to have ingested this substance? a) 1 week b) 5 weeks (embryonic stage when important organs are being developed) c) 8 weeks New Section 1 Page 3 c) 8 weeks d) 16 weeks e) 25 weeks *It is possible for women who did not realize that they were pregnant to experience miscarriage from consuming teratogen Newborns and Beyond The average neonate (newborn) spends the majority of the day sleeping (usually 16h out of 24h), and awake only for 5h *Sometimes, babies cry for no reason and therefore parents choose to leave them in a safe space, instead of taking care of them (communicative --> need something, non-communicative --> just crying) Neonatal Sleep Yellow: awake, red: REM sleep, blue: non-REM sleep Ex: to find the average sleeping time of 23 olds, find the coordinate of the according x-axis and y-axis Newborns need lots of sleep in order to grow up Perceptual Development Even though perceptual development begins in utero, the experiences are richer after birth a) Sensation: sensory organs detection of physical signals in the environment b) Perception: organization and interpretation of the sensory information into coherent understanding of objects, individuals, events Measuring Infant's Perception New Section 1 Page 4 Measuring Infant's Perception How does a baby's reaction change toward the stimuli? Preferential looking Infants choose to spend more of their time looking at objects and events that are interesting, stimulating, or familiar Ex: They can see well enough to differentiate a mother and other woman Visual acuity Grating visual acuity test: even though babies prefer stripes over plain color, they cannot distinguish them as their vision in the first few months are not that good In the first month of life, infants' visual acuity increase from approximately 20/400 to approximately 20/120 Adults like acuity at 6 months Color perception and depth perception also develop at the first 6 months Motor Development in Infancy Infants' ability to move also develop when the perception is developing Newborns' motor skills are mostly consisted of reflexes, while some of them can last for the entire lifespan: Grasping, rooting, sucking, swallowing, tonic neck reflex, coughing, sneezing, blinking, withdrawal from pain New Section 1 Page 5