Invitation to the Life Span
by Kathleen Stassen Berger
Chapter 1– The Science of
PowerPoint Slides developed by
Martin Wolfger and Michael James
Ivy Tech Community College-Bloomington
Defining Development
The science of
seeks to understand
how and why
people—all kinds of
people, everywhere,
of every age—change
over time.
Understanding How and Why
Five basic steps of the scientific method:
• On the basis of theory, prior research, or a personal
observation, pose a question.
• Develop a hypothesis, a specific prediction, that can be
• Test the hypothesis. Design and conduct research to
gather empirical evidence (data).
• Draw conclusions. Use the evidence to support or refute
the hypothesis.
• Report the results. Share the data and conclusions, as
well as alternative explanation.
The Nature-Nurture Debate
• Nature refers to the influence of genes
which we inherit.
• Nurture refers to environmental
influences, such as:
health and diet of the embryo’s mother
Critical and Sensitive Periods
• A critical period is a time when certain
things must occur for normal development.
• A sensitive period is when a particular
development occurs most easily.
The Life-Span Perspective
Development is multidirectional
• Over time, human characteristics change in
every direction.
• Several major theorists describe stages of
development: Freud, Erickson, Piaget.
• Others view development as a continuous
The Life-Span Perspective
Development Is Multicontextual
• HISTORICAL CONTEXT- All persons born
within a few years of one another are said to be
a cohort, a group defined by the shared age of
its members.
The Life-Span Perspective
Socioeconomic Context
socioeconomic status (SES)
A person’s position in society as determined by
income, wealth, occupation, education, and
place of residence.
When does low SES do most damage to human
The Life-Span Perspective
Development Is Multicultural
• Culture - patterns of behavior that are passed
from one generation to the next.
• Vygotsky described the interaction between
culture and education. (guided participation)
• Ethnic group - People whose ancestors were
born in the same region and who often share a
language, culture, and religion
The Life-Span Perspective
Development Is
• Genetics and
neuroscience are two of
the newer disciplines in
lifespan research.
• Every trait—psychological
as well as physical—is
influenced by genes.
The Life-Span Perspective
Development Is Plastic
• Human traits can be molded (as plastic can be),
yet people maintain a certain durability of
identity (as plastic does).
• Mirror neurons- Cells in an observer’s brain that
respond to an action performed by someone
else in the same way they would if the observer
had actually performed that action.
Theories of Human
A developmental theory is a systematic
statement of principles and generalizations
that provides a framework for
understanding how and why people
change as they grow older.
Theories of Human
Psychoanalytic Theory
• A theory of human development that holds that
irrational, unconscious drives and motives, often
originating in childhood, underlie human
• Psychoanalytic theory originated with Sigmund
Freud (1856– 1939)
Theories of Human
Erickson’s Stages
• Erik Erikson (1902–1994)
• Described eight developmental stages, each
characterized by a challenging developmental
• His first five stages build on Freud’s theory; but,
he also described three adult stages.
Theories of Human
Theories of Human
• A theory of human development that studies
observable behavior. Behaviorism is also called
learning theory, because it describes the laws
and processes by which behavior is learned.
• Conditioning- According to behaviorism, the
processes by which responses become linked to
particular stimuli and learning takes place.
Theories of Human
Classical conditioning - Ivan Pavlov
• (also called respondent conditioning), a process
in which a person or animal learns to associate
a neutral stimulus with a meaningful stimulus,
gradually reacting to the neutral stimulus with
the same response as to the meaningful one.
Theories of Human
Operant conditioning - B.F. Skinner
• (also called instrumental conditioning) a learning
process in which a particular action is followed
either by something desired (which makes the
person or animal more likely to repeat the
action) or by something unwanted (which makes
the action less likely to be repeated).
Theories of Human
Theories of Human
Social Learning Theory - Albert Bandura (b.
• An extension of behaviorism that emphasizes
the influence that other people have over a
person’s behavior.
• Modeling- people learn by observing other
people and then copying them.
• Self-efficacy- (how effective people think they
are when it comes to changing themselves or
altering their social context.
Theories of Human
Cognitive Theory
• Thoughts and expectations profoundly affect
• Focuses on changes in how people think over
• Jean Piaget (1896–1980)
Theories of Human
Theories of Human
• Assimilation, in which new experiences
are interpreted to fit into, or assimilate
with, old ideas
• Accommodation, in which old ideas are
restructured to include, or accommodate,
new experiences
Theories of Human
Systems Theory
• Change in one part of a person, family, or society
affects every aspect of development
Ecological systems approach- Urie
Bronfenbrenner (1917–2005)
• The person should be considered in all the
contexts and interactions that constitute a life.
• (bioecological)
Theories of Human
Five Components of Bronfenbrenner’s
• microsystems (elements of the person’s
immediate surroundings, such as family and
peer group)
• exosystems (local institutions such as school
and church)
• macrosystems (the larger social setting,
including cultural values, economic policies, and
political processes)
Theories of Human
• chronosystem (literally, “time system”), which
affects the other three systems
• mesosystem, consisting of the connections
among the other systems
Using the Scientific Method
Scientific Observation
• requires the researcher to record behavior
systematically and objectively.
• May be done in a naturalistic setting such as a
home, school, or other public place.
• May be done in a laboratory.
Using the Scientific Method
The Experiment establishes causal
relationships among variables.
• independent variable- the variable that is
introduced to see what effect it has on the
dependent variable.
• dependent variable- the variable that may
change as a result of whatever new condition or
situation the experimenter adds.
Using the Scientific Method
• experimental group- gets a particular
treatment (the independent variable).
• comparison group (also called a control
group), which does not get the treatment.
Using the Scientific Method
Using the Scientific Method
The Survey
• Information is collected from a large number of
people by interview, questionnaire, or some
other means.
• Acquiring valid survey data is not easy.
• Some people lie, some change their minds.
• Survey answers are influenced by the wording
and the sequence of the questions.
Studying Development over the
Life Span
Cross-sectional Research
• Groups of people of one age are compared with
people of another age.
Longitudinal Research
• Collecting data repeatedly on the same
individuals as they age.
Cross-sequential Research
• Study several groups of people of different ages
(a cross-sectional approach) and follow them
over the years (a longitudinal approach).
Cautions from Science
Correlation and Causation
• A correlation exists between two variables if
one variable is more (or less) likely to occur
when the other does.
• A correlation is positive if both variables tend to
increase together or decrease together.
• A correlation is negative if one variable tends to
increase while the other decreases.
• A correlation is zero if no connection is evident.
• Correlation is not causation
Each academic discipline and professional
society involved in the study of human
development has a code of ethics.
• Researchers must ensure that participation is
voluntary, confidential, and harmless.
• Subjects (participants in research) must give
informed consent- they must understand the
research procedures and any risks involved.

Invitation to the Life Span by Kathleen Stassen Berger