PSYCH 244 - Chapter 1

Developmental psychology

Scientific approach to study of constancy and change across the lifespan

Why study child development?

• Raising children (e.g. crying is normal)

• Social policy (biased questioning affects the accuracy of children's memory)

• Human nature

Leading questions

Questions that bias answers in a specific direction (e.g. asking “where did this person touch you?” without the child saying they were touched)

Nativists

Believe evolution has created remarkable capabilities that are present even in early infancy

empiricists

infants possess general learning mechanisms that allow them to learn quickly, but infants and young children lack the specialized capabilities that nativists attribute to them

Romanian adoption study

The impact of positive experiences on children's resiliency depends on the timing and extent of the neglect.

• children could overcome effects of not being loved as long as they were adopted by 6 months → older children couldn’t overcome completely

• the later the adoption, the greater the long-term harmful effects

• developmental differences mostly apparent in the prefrontal cortex (reasoning), social differences seen by low neural activity in the amygdala

Theme 1: Nature and Nurture

• genetics/biology vs. environment

• Plato + Socrates - innate knowledge (nature)

• Aristotle - we are a product of our experience (nurture), concerned with fitting child rearing with the needs of the individual child

• Locke - tabula rasa → need discipline (nurture), parents need to set a good example

• Rousseau - born with what you need to succeed (nature), learn from spontaneous actions, need freedom from the beginning, should not receive formal education till the age of 12

Epigenetics

The study of stable changes in gene expression that are mediated by the enviornment

• methylation reduces expression of a variety of genes and is involved in regulating stress → if mothers are stressed during pregnancy, they will have increased methylation which in turn makes their newborn depressed

Theme 2: Continuity and Discontinuity

• Continuous - Cumulative process, adding 'more’ of same type of skill/function/process (e.g. muscle building)

• Discontinuity - Reorganizations or additions of qualitatively different skill/function/process/etc, new ways of interacting with the world (e.g. baby steps)

• not always clear cut (e.g. Thelen and the stepping reflex)

• often depends on analysis

• u-shaped curve - infants lose a reflex but then it comes back

Stage (discontinuity)

Distinct and separate period of development

• qualitative changes

• discontinuities

• clear-cut boundaries

• uniform “nature” within a stage

• universal across children and cultures

• Freud, Erikson, Piaget, Kohlberg

e.g conservation-of-liquid problem shows a difference between 4 and 6 years

Stages of development

1. prenatal - conception through birth

2. infant and toddler - birth to age two

3. early childhood - 2-6 years

4. middle childhood - 6-11 years

5. adolescence - 11-20 years

6. adulthood

Theme 3: Child’s role in development

• reciprocal determinism - child affects enviornment, environment affects child

• accumulation of interests

• role strengthens w/age

• selective attention - newborns pay more attention to objects that move + make sounds

• around 9-15 months, they start speaking by talking to themselves

• play teaches valuable lessons (e.g. resolving disputes)

Theme 4: Mechanisms of change

• How does change occur? → biologically determined, variability (e.g. house with carpets are more likely to crawl), input specific?

• Domain specific (development affects only one skill) vs. domain general

• Study of stats and transitions

• may need several mechanisms for a certain skill (e.g. language development is cognitive and motor)

• development of effortful attention - controlling emotions and thoughts due to increases connections between the limbic area and anterior cingulate and prefrontal cortex

Role of sleep

Maturation of the hippocampus

• first 18 months - sleep promotes general learning (frequently encountered patterns, not specifics → functioning of cortex

• after 24 months - remember specifics better than those who did not nap, but the general memory was the same → functioning of hippocampus

Theme 5: Sociocultural context of development

• How does socio-cultural context affect development?

• Some features of development constant no matter what culture/circumstances?

• How does socio-cultural context interact with other features

• Are the theories of development that we have applicable to other cultures?

• Are the research methods that we use appropriate across cultures (e.g. worksheet culture vs. on-ground)?

Sleeping arrangements

• In US, infants stop sleeping w/parents around 2-6 months, and then there is a ritual of bedtime activities, children bring a comfort object to bed → not present in other cultures due to differences in values

Cumulative risk

accumulation of disadvantages over years of development

• leads to positive personal qualities (e.g. optimism)

• close relationship w/at least one parent

• close relationship w/at least one adult other than parents

Theme 6: Individual differences

• Why are children so different in seemingly similar environments?

• Do similar mechanisms account for development across individuals?

• Risk factors?

• Resiliency factors?

• Normative development issues

differences in genetics, treatment by parents and others, reactions to similar experiences, choice of enviornment

Theme 7: Research and children’s welfare

• How can the science of child development improve the lives of children?

Longitudinal design

• study same set of people over time

• any time length, but often a few weeks or months

• can go on for years or decades

• Advantages: identify common patterns and individual differences, learn about the process of change, study relationship between early events and later behavior

• Disadvantages: biased sampling (not everyone is willing to participate), selective attrition (people drop out; their characteristics are important), practice effects (familiarity after taking the measure several times), cohort effects (generational difference, drawing conclusions based on common experience), theory/question may become outdated

• used for stability + change over time

Cross-sectional design

• groups of different ages studied at the same time

• eliminates selective attrition, practice effects, and theory/question change

• Advantages: great way to find age differences, good for examining normative (average) differences between children of different ages, economical (doesn't take a lot of time or money)

• Disadvantages: ignores processes underlying differences, confounds age + cohort effect (don’t know if results are due to maturity or generational differences)

• used for age-related changes

Longitudinal-sequential design

• follow groups for a period of time

• helps examine cohort effects

• can make longitudinal and cross-sectional comparisons

• more efficient

• Advantages: can tease apart age/time/cohort effects, can look at wider age range of subjects over a shorter time interval

• Disadvantages: costly with time and money, data analysis and interpretation can be more challenging

Microgenetic designs

• large number of observations or measurements over a very short interval

• tries to target an important transition period (e.g. onset of walking or a new cognitive skill)

• make intensive observations around that transition period

• Advantages: great for understanding what causes a transition, not as costly as longitudinal designs in both time and money

• Disadvantages: hard to determine transition points, practice effects, need to have lots of time in a short period, can only use this approach for a few subjects

Ethics

• Ultimate responsibility lies with researcher

• Children more vulnerable to harm

• Immaturity affects understanding of results of participating

• Special ethical guidelines for kids (e.g. parental consent)

• Risk vs. benefits ratio → risks weighed more for kids

• Protection from harm

• Assent to participate

• Children trust adults

• Issues in deception

• Debriefing

The scientific method

choosing a question, formulating a hypothesis, testing it, conclusion

reliability

the degree to which independent measures of a given behavior are consistent

interrater reliability

the amount of agreement in the observations of different raters who witness the same behavior

test-retest reliability

the degree of similarity of a participant’s performance on two or more occasions

validity

the degree to which a test measures what it’s supposed to measure

Internal validity

The degree to which effects observed within experiments can be attributed to the factor the researcher is testing

External validity

The degree to which results can be generalized beyond the particulars of research

Replicability crisis

Causes: too few participants, file-drawer problem - researchers “file away” studies that fail to yield predicted results, subsequent studies fail

Solutions: journals requiring large samples, journals requiring preregistration where researchers submit their planned methods and analyses, so that reviewers base publication on methodological rigor rather than results, both original and new investigators collaborate

Structured interviews

all participants are asked the same questions, oral for young children, questionnaires for children who can read

Clinical interview

begins with set questions but then adjusts based on child’s responses

Pros: yield great data quickly

Cons: biased questions

Naturalistic observation

Examination of ongoing behavior in an uncontrolled environment

• useful for everyday interactions

• Limitations: naturally occurring contexts vary on many dimensions → difficult to conclude how the current situation arose, many behaviors of interest occur only occasionally in the everyday environment

Structured observation

presenting an identical situation to each participant recording their behavior

• does not provide information about subjective experience or everyday data

direction-of-causation problem

the correlation between two variables does not indicate which, if either, variable is the cause of the other

third-variable problem

the correlation may stem from a third variable influence