Chapter 1 Summary
1.1 Understanding How and Why
science of human development
The science that seeks to understand how and why people of all ages and circumstances change or remain the same over time.
scientific method
A way to answer questions using empirical research and data-based conclusions.
1.Begin with curiosity. Consider theory, study research, observe closely, question assumptions. Develop a hypothesis, a specific prediction arising from the question raised in step one.
2.Test the hypothesis.
3. Design a study and conduct research to gather empirical evidence.
4.Draw conclusions. Use evidence (Step 3) to support or refute the hypothesis (Step 2). Consider alternate interpretations, unexpected results, and possible biases.
5.Report the results. Share data, conclusions, and limitations. Suggest further research to explore new questions (back to Step 1).
hypothesis
A specific prediction that can be tested, and proven or disproven.
replication
Repeating a study, usually using different participants, perhaps of another age, SES, or culture.
nature
In development, nature refers to genes. Thus, traits, capacities, and limitations inherited at conception are nature.
nurture
In development, nurture includes all environmental influences that occur after conception, from the mother’s nutrition while pregnant to the culture of the nation.
differential susceptibility
The idea that people vary in how sensitive (for better or worse) they are to particular experiences, either because of their genes or because of their past experiences. (Also called differential sensitivity.)
adverse childhood experiences (ACEs)
Childhood experiences that have been proven to have harmful effects on development. Physical and emotional problems in adulthood can be traced to ACEs.
1.2 The lifespan perspective
life-span perspective
An approach to the study of human development that includes all phases, from birth to death, and that considers many changes in direction, culture, and context.
critical period
Time when a particular development must occur. If it does not, as when something toxic prevents that growth, then it cannot develop later.
sensitive period
A time when a particular developmental growth is most likely to occur, although it may still happen later.
ecological-systems approach
A perspective on human development that considers all of the influences from the various contexts of development. (Later renamed bioecological theory.
cohort
People born within the same historical period who therefore move through life together, experiencing the same events, new technologies, and cultural shifts at the same ages.
culture
A system of shared beliefs, norms, behaviors, and expectations that persist over time and prescribe social behavior and assumptions.
social construction
An idea that is built on shared perceptions, not on objective reality.
difference-equals-deficit error
The mistaken belief that a deviation from some norm is necessarily inferior.
ethnic group
People whose ancestors were born in the same region. Usually they share a language, culture, and/or religion.
race
The concept that some people are distinct from others because of physical appearance, typically skin color. Social scientists think race is a misleading idea, although race can be a powerful sociological idea, not based in biology.
socioeconomic status (SES)
A person’s position in society as determined by income, occupation, education, and place of residence. (Sometimes called social class.)
plasticity
The idea that abilities, personality, and other human characteristics are moldable, and thus can change.
dynamic-systems approach
A view of human development as an ongoing, ever-changing interaction between the physical, cognitive, and psychosocial influences.
1.3 Theories of Human Development
developmental theory
A group of ideas, assumptions, and generalizations about human growth. A developmental theory provides a framework to interpret growth and change.
behaviorism
A theory of human development that studies observable actions. Behaviorism is also called learning theory because it describes how people learn to do what they do.
operant conditioning
The learning process that reinforces or punishes behavior. (Also called instrumental conditioning.)
reinforcement
In behaviorism, the positive experience that follows a behavior, making it likely that the behavior will occur again.
social learning theory
A theory that emphasizes the influence of other people. Even without reinforcement, people learn via role models. (Also called observational learning.)
cognitive theory
A theory of human development that focuses on how people think. According to this theory, our thoughts shape our attitudes, beliefs, and behaviors.
evolutionary theory
When used in human development, the idea that many current human emotions and impulses are a legacy from thousands of years ago.
1.4 Doing Science
survey
A research method in which information is collected from a large number of people by interviews, written questionnaires, or some other means.
scientific observation
Watching and recording participants’ behavior in a systematic and objective manner — in a natural setting, in a laboratory, or in searches of archival data.
experiment
A research method in which the researcher adds one variable (called the independent variable) and then observes the effect on another variable (called the dependent variable) in order to learn if the independent variable causes change in the dependent variable.
independent variable
In an experiment, the variable that is added by the researcher to see if it affects the dependent variable.
dependent variable
In an experiment, the variable that may change as a result of the independent variable (whatever new condition the experimenter adds). In other words, the dependent variable depends on the independent variable.
cross-sectional research
A research design that compares people who differ in age but not in other important characteristics.
longitudinal research
A research design that follows the same individuals over time.
cross-sequential research
A hybrid research design that includes cross-sectional and longitudinal research. (Also called cohort-sequential research or time-sequential research.)
1.5 Cautions and Challenges from Science
correlation quantitative research
Usually a number between +1.0 and −1.0 that indicates whether and how much two variables are related. Correlation indicates whether an increase in one variable will increase or decrease another variable. Correlation indicates only that two variables are somehow related, not that one variable causes the other to increase or decrease.
quantitative research
Research that provides data expressed with numbers, such as ranks or scales.
qualitative research
Research that considers individual qualities instead of quantities (numbers).