Development of Child and Youth
theories of development
- literary sources from multiple cultures indicate a strong and abiding interest in development and developmental processes - naive theories/folk knowledge - rise of scientific analysis of development
clinical method STRENGTHS
- present a structured task or stimulus, invite a response; follow with questions to clarify - flexible approach - treat each as individual
clinical method WEAKNESSES
- responses may not be comparable - interpretation of responses may be subjective
chronology of development can be described as occurring in several stages:
1. prenatal period (conception to birth) 2. infancy (birth to 18 months old) 3. toddlerhood (18 months old to 3 years old) 4. preschool period (3 to 5 years of age) 5. middle childhood (5 to 12 or so years of age until the onset of puberty) 6. adolescence - girls experience earlier than boys (12 or so to 20 years of age (many developments define the end of adolescence as the point at which the individual begins to work and is reasonably independent of parental sanctions)) 7. young adulthood (20 to 40 years of age) 8. middle age (40 to 65 years of age) 9. old age (65 years of age of older)
detecting relationships in the data: the correlational, experimental and quasi-experimental methods
3 forms of design: CORRELATIONAL: researcher examines nature of relationships in unmanipulated variables EXPERIMENTAL: researcher changes nature of one or more variables and examines the effect of the change on another variable QUASI EXPERIMENTAL: researcher examines both correlational and experimental variables in the same design
Development is:
A CONTINUAL AND CUMULATIVE process: - change at any point in development has an impact on future development A HOLISTIC PROCESS: - development is due to a combination of changes in physical growth, cognitive aspect of development, psychosocial aspects of development
Maturation (sources of developmental pressure)
the unfolding over time of a biological potential 2 sources: - species typical biological inheritance (nature of development as human species, girls > vagina, boys > penis) - individual biological inheritance (what have you gotten from your parents? look like parents etc.)
Normative development
typical patterns. what do we see amongst individuals (2 year olds can speak a little but not like adults)
experiment
only a study in which the researcher manipulates at least one variable is an experiment.
Experimental design: field experiments
In field experiments, a researcher manipulates a variable in the environment and looks for its effect on behavior. example: an advertizing campaign is presented in one city and buying patterns of those viewing the campaign and compared to buying patterns of people in other cities. Effect of IV can be highly variable: it may be stronger or weaker in this type of experiment.
Goals of developmental psycholgists
TO DESCRIBE: based on observations - Normative development - Ideographic development TO EXPLAIN: address the why of development; often requires experimentation TO OPTIMIZE: to help development move in positive directions: intervention directed towards improvement. best developmental outcome for children (goal).
Experimental design: Quasi-Experiments
The quasi-experiment uses naturally occurring events, characteristics, or experiences as grouping variables although they are not true independent variables because the participants cannot be assigned to the groups randomly. example: the response of people who experience an earthquake vs. those who only read about it vs. those who dont know it happened studies using grouping variables that the experimenter cannot control or assign (like age, sex, race of ethnicity, personality characteristic, type of experience) are quasi-experimental not true experiments. quasi-experiments cannot demonstrate true causality developmental experiments are quasi-experiments as the researcher cannot assign children to be a particular age.
case study
a detailed description of a single individual or group of individuals - strength: depth of information - limitations: difficult to compare individuals, sample is limited so results may not generalise
Age as a variable in research
because developmentalists are interested in age-related changes and continuities, age is an important variable in developmental research. 3 principal techniques: - cross-sectional design - longitudinal design - sequential or cohort-sequential design
plasticity
capacity for change in response to experience
limitations of the correlational design (LIMITATIONS)
correlations do not indicate causality causal direction of relationship is unknown and unknowable: A could cause B or B could cause A Relationship could be due to a third (or fourth) unmeasured variable and not the ones being studied
cultural/historical context
culture & history provide a context in which development occurs culture & history may influence factors the inhibit of facilitate development - historical and cultural beliefs about positive childrearing outcomes - historical and cultural beliefs about nutrition or education
scientific method
empirical - based in collection & analysis of information objective - anyone examining the information will reach the same conclusion replicable - anyone using the same methods for data collection will get the same results and draw the same conclusions publicly shared - researcher shares results with others who can critique and replicate results
limitations of the correlational design (BENEFITS)
existence of correlation may lead to more definitive research it may only be possible to study some variables correlationally
Experience or learning (sources of developmental pressure)
experiences produce relatively permanent changes
development
focus of the field of developmental psychology there are many commonalities defined as SYSTEMATIC CHANGE AND CONTINUITIES (predictable) (^opposites) that are: - Orderly - exhibit stability
ethnography
gather data by living in a culture or community for an extended period of time
quasi-experimental
if a grouping variable is employed with a manipulated variable
correlational study
if no variable is manipulated
longitudinal designs
in longitudinal designs, the same people are assessed at different ages. design can assess both continuity and change within individuals and can establish normative trends BUT, it is costly & time-consuming. there may be practice effects that influence performance. Selective Attrition or Subject Mortality- participants may drop out over time, reducing the number in the study. Is especially problemmatic if reason for attrition is related to study variables. cohort effects are not eliminated.
interviews
individual approach, lots of depth - structured interviews ask same questions of all respondents - unstructured interviews ask broad questions and ask for clarification of responses - self reporting biases - time consuming for fewer participants - time consuming analysis
Ideographic development
individual patterns. development amongst individuals. rate varies from person to person. (all children crawl before they walk)
questionnaires
lots of data, little depth - self administered, thus large amounts of data can be gathered - self reporting bias - requires literacy - have you asked the "right" questions? - data are easily analysed but lack specificity
basic assumptions in measurement
measures can be made in variety of forms: observations, self-reports, experiments, questionnaires, diaries, etc. BUT all measures should show to two characteristics: - measures should be RELIABLE: the measurement should be consistent across time and across individuals doing the measurement - measures should be VALID: the measurement should measure what it is supposed to measure
structured observations
occur in an artificial environment more control, less realistic benefits - all participants observed in same environment - low frequency behaviors can be elicited - observation may be masked deficits - may not represent real-life - anxiety or strangeness may influence behaviour
naturalistic observations
occur in naturally occurring environment less control, more realistic benefits: - behavior is "real-life" - easily applied deficits: - complex, uncontrollable environment - low-frequency behaviors may not occur - presence of observer may alter behavior - difficult to isolate cases and consequences
theory
organized set of concepts and propositions that describe and explain some aspects of behaviour - should generate hypotheses - may be macro theory (all types of behavior) or micro theory (restricted type of behavior) - occam's razor: observable are preferred to non-observables; simpler explanations are often better
cross cultural designs
participants from different cultures are assessed and compared OR people within the same (but previously unassessed) culture are assessed. allows researchers to identify cultural factors that influence development reduces the danger of over-generalizing findings this is a quasi-experimental design (researcher cannot assign participants to different cultures)
cross-sectional designs
people of different ages are studied at the same point in time; each person is assessed once people of the same age are called a COHORT. cohorts share experiences and characteristics in addition to age allows researcher to compare people of different ages research is relatively inexpensive as there is no need to keep track of participants over time BUT people born at different times are from different cohorts. cohort and age are cofounded variables. Age differences may be cohort effects not developmental change because each person is assessed only once, no data are available on individual development. Thus, we cannot assess change or continuity, merely age differences. nonetheless, cross-sectional research represents the vast majority (over 75%) of developmental research
Experimental design
problem with correlational designs is that confounding variables may exist that influence one or more DVs experimental designs minimize confounds by randomly assigning participants to groups experiencing different levels of the independent variable (IV). An experiment may have more than one IV. Experiments often use control groups as basis for comparisons often we use operationally defined variables in research (for example, aggression defined as hitting a punching bag rather than a person). ONLY EXPERIMENTS CAN DEMONSTRATE CAUSAL RELATIONSHIPS
psychophysiological methods
psychophysiological measurement examine relationship between physiological responses and behaviour - heart rate decreases when new or novel stimuli presented; assumed to be linked to interest or attention. changes in blood pressure may indicate emotional responses - EEGs/ERPs: brain wave patterns show arousal states - hormone levels (e.g. oxytocin levels predicting attachment) some physiological measures may be contaminated by means of measuring (e.g. increased anxiety due to equipment) interpretation is problematic
sequential (cohort-sequential) designs
sequential (or cohort-sequential) designs combine longitudinal and cross sectional designs. people of different cohorts (ages) are assessed over time. strengths: -can analyze for cohort effects -more efficient than longitudinal design: takes less time & less subject attrition -allows researcher to observe individual continuity and change
hypotheses
specific predictions about relationships among variables - must be testable & falsifiable
developmental psychology
subfield within the broader field of psychology begin development at conception (first born till die) and continue to develop throughout our lives
microgenetic design
use the microgenetic design to examine processes that promote developmental change -expose children ready for a developmental change to experiences thought to promote that change -monitor behavior as it changes limitations: -time consuming to track large numbers of children in a detailed fashion -repeated assessments may influence the outcomes being studied
correlational research
used with naturally occurring phenomena or variables (such as age, sex, race) that the researcher cannot manipulate or change correlation coefficient (abbreviated as r) used to indicate strength & direction of relationship; can range from -1.0 + 1.0 value indicates strength of relationship; sign indicates direction positive correlation: high scores associated with high scores and low scores with low scores negative correlation: high scores on one variable associated with low scores on the other zero or non-significant correlation: no relationship demonstrated statistically between the variables
independent variables
variables we manipulate in research ex. is teaching method A better than method B for teaching students to read? Teaching method (A vs. B) is the IV. ("Reading skills" at the end of the study will be the DV.)
dependent variables
variables we measure in research ex. how does alcohol consumption affect driving abilities? Driving abilities would be the DV