Processes in cellular development:mitosis: process of cellular divisioncell migrationCell differentiationEmbryonic stem cells: can develop into any kind of cellWolperf (1991): frog embryos to be eye cells transplanted to stomachEarly development: become stomach cellsLate development: lone, unseeing eye on stomachApoptosis: genetically-programmed cell death2. Cephalocaudal Development: development from head downupper half of embryo/fetus more advanced than lower halfandrogens: class of hormones that produce typically male characteristicsex. Facial hair, deepened voiceestrogens: class of hormones that produce typically female characteristicsex. Bone structure of female pelvisStage 1: the zygoteAka germinal stageConception 2 weeksFallopian tube womb (40% of conceptions)Mitosis: first division15 hrs.Blastocyst: inner ball of cellsStage 2: the embryo2 weeks2 monthsbegins after implantation in uterine wall2 fetal membranes:chorion: outer membrane(placenta)amnion: inner membrane (amniotic sac)cellular differentiation beginsorganogenesisendoderm: inner mass of blastocyst cellsrespiratory & digestive systems, liver, pancreasmesoderm: middle mass of blastocyst cellsmuscles, bones, blood, heart, kidneysectoderm: outer mass of blastocyst cells10 weeks: breathing movements begin (no air in amniotic sac, but fluid)infrequent, irregular at firstphysical movement:12 weeks: most newborn capable movements; mother begins to feel movementmovement increases until about 20th week, then declines until birth.Hopson (1998): by 32 weeks, fetus sleeps 90-95% of the timeLevel of activity of 36 weeks (prenatal)Level of activity at 1 year oldPSY 240 1st EditionDevelopmental Psychology Midterm 1Themes and Research in Developmental Psychology- How do each of the following debates inform developmental psychology?o nature vs. nurture Nature: biology, genes- Genome: individual’s complete set of DNA Nurture: environment, experiences Nature “vs” nurture? Both!- Epigenetics: study of changes in gene expression due to environment.oo continuity vs. discontinuity discontinuity: traditional view -developmental occurs in discrete stages (qualitative change)- -Continuity: modern view- -constant, gradual development over time (quantitative change)o stability vs. change Personality & attachment style- -anxiety- -Shyness- -aggressivenesso processes of change -Cross-sectional vs longitudinal studies- Cross-sectional study: utilizes different groups of people who differ in the variable of interest, but share other characteristics. Are observational in nature and is known as descriptive researcho -takes place at a single point in time, no manipulating variables, allows researchers to look at numerous things at once- Longitudinal Studieso Focus on mediation- -cause mediator effecto role of context (especially culture) physical, social, cultural, economic, historical -socioeconomic status (SES): measure of social class, based on income and education- -Bradley & Corwyn (2002): higher SES families healthier children, better academic achievement.- -Culture:  societal progress, beliefs, traditions, etc.- E.g Where should children sleep?- US: parent’s room until 2-6 months, then own room- -many other cultures: much longer, same bed (as mother)?- -What does a culture value?- - ex. Independence vs. interdependence- -morelli et al (1992); cross-cultural study on sleeping arrangements- US: nighttime separation important part of learning self-reliance- -ritualistic separation: ~50% bring comfort object to bed- -Guatemala: sleeping together important part of mother-child bond- -no bedtime rituals, comfort objectso role of individual differences mostly focus on commonality (esp. within culture) but genetic difference: - -siblings share 50% of genes- -fraternal twins: 50%- -identical twins: 100% -different treatment by adults -subjective interpretation of adult treatment -activity levelo child’s active role in development -are young children better compared to a sponge, or a lump of clay?- -traditional view: infants as “blank slate” (incompetent, passive)- -modern view: active engagement- What are the 4 steps to the scientific method?  Step 1: Choose a research question (previous research, current events, personal interests, etc.)- Step 2: create a hypothesis- -Hypothesis: a prediction about the outcome of a study- Step 3: Test the hypothesis- Step 4: interpret data, evaluate hypothesis- What is the difference between a hypothesis and a theory? Create evidence-based theories by testing hypotheses-Theory: integrated set of principles that explains outcomes of studies o -Hypothesis Research  Theory- What is an operational definition?o -operational definition: the specific way that a variable is manipulated or measured in a study- -How could we operationalize aggression?o- What is descriptive research, and what are its strengths and weaknesses? What is the differencebetween a clinical interview and a structured interview? What is the difference between a structured observation and a naturalistic observation? What are the strengths and weaknesses of each?o Descriptive research: describes characteristics of developing person  We ask them.. Surveysstructured interview: ask children about their lives- same questions for all P’s; scriptedclinical interview: in depth interview with one childstructured observation: present same situations to all p’s, record reactionsnaturalistic observation: observing children in natural uncontrolled environments-strengthso- What is correlational research, and what are its strengths and weaknesses? How do you interpret the size and the direction of a correlation?Correlational research: measures association between two variables not manipulated by researcher-does a change in one variable predict a change in the other?correlation coefficient: (-1 to +1) direction and sizepositive correlations: as one variable increases, so does the other-height & weight; health & incomenegative correlations: as one variable increases, the other decreases- self-esteem & depressionzero correlations: no correlation small correlations: .10 to .29 (+/-)moderate correlations: (.30 to .49 (+/-)o large correlations: .50 to 1.00 (+/-) the larger the correlation, the more predictive it is. - Pros and cons of correlational research: Pros: quick and easy- -when variables can’t be manipulated  Cons: -