Chapter One
The Study of Development in Adulthood
“Youth is a gift of nature; age is a work of art.” Anonymous
Learning Objectives
After reading this chapter:
•
The student will acquire an understanding of adult development as a field of study, including key terms and
perspectives, and the impact of changing demographics on the field and society.
•
The student will understand the major research methods and designs used in developmental psychology and
the advantages and disadvantages of each, and will be able to evaluate research reports.
•
The student will develop an appreciation of the limitations in the available research and be aware of
concerns about various forms of bias.
Chapter Outline
I.
Adult Development as a Field of Study
A. Psychology is the scientific study of behavior and mental processes.
B. Developmental psychology is the subfield of psychology that examines the direction of change in
the individual over time.
1. Development is the systematic changes in behavior over time that results from
interaction between the individual and the internal and external environment.
2. Adult development is the branch of developmental psychology concerned with change
in the individual after adolescence.
3. Adulthood is characterized by relative independence from parents and the acceptance of
responsibility for one’s actions.
C. Gerontology is the scientific study of aging.
II. Demography and the Changing View of Adulthood
A. Prior to World War II, most research in developmental psychology focused on children and
adolescents.
B. Demographic trends shifted the focus to adulthood in the latter half of the 20th century.
1. The average life expectancy is now about 77.
2. Adults today are healthier and more active.
a. Distinctions are now being made between chronological age (age in years) and
functional age (competence and performance age).
b. The young-old are being distinguished from the old-old.
3. The baby boom (the largest generation in U.S. history born between 1946 & 1964) was
followed by a baby bust.
4. Changes in the size and shape of the U.S. population moved the age structure from a
traditional population pyramid to a more rectangular structure.
C. Why study adult development?
1. The study of adult development helps us to understand the needs and capabilities at all
stages of adult life, including old age.
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2.
The study of adult development may help to dispel misconceptions of aging and
subsequent discrimination.
III. A Life-Span Developmental Perspective
A. Life-span development refers to the study of age-related changes from conception to death.
B. Six key perspectives on life-span development have been identified.
1. Development is a lifelong process (life-span developmental perspective).
2. Development includes both gains and losses.
3. Development is multidimensional, multidirectional, and multicausal.
4. Development is plastic (plasticity).
5. Development is embedded in historical, cultural, and social contexts.
a. Normative age-graded influences include universally experienced events
closely tied to an individual’s age.
b. Normative history-graded influences are the result of forces operating during
a particular historical era.
i. A cohort is defined as a group born at about the same time and place.
ii. Cohort effect is the effect of the year of birth and subsequent
sociohistorical experience on development.
c. Non-normative influences are unique experiences that contribute to our unique
development.
6. Development is a multidisciplinary field.
IV. Research Concepts, Methods, and Design
A. Two key concepts guide research.
1. Reliability refers to the consistency of results over time.
a. Test – retest reliability is the extent to which a subject receives comparable
scores when retested.
b. Interobserver reliability refers to consistency in the rating or judgments made
by independent observers.
2. Validity refers to whether the study examined what the investigator meant to study in the
first place.
a. Construct validity refers to the quality and appropriateness of the tool used for
measuring a particular aspect of behavior.
b. Predictive validity refers to how well performance on a test predicts actual
performance in real life.
c. Internal validity refers to the extent to which we can draw conclusions about
the causal effect that one variable has on another.
d. External validity has to do with the generalizability of research results to
specific populations and/or settings.
B. Formulating a Hypothesis
1. The first step in scientific research is formulating a hypothesis.
2. A hypothesis is a tentative explanation for the behavior under investigation – a best
guess.
C. Methods of Collecting Data
1. Naturalistic observation (field method) involves describing the behavior of subjects in
a real-life setting (the field).
a. Being able to describe real life behavior, as opposed to the more artificial
behavior seen in a laboratory, is an advantage.
b. Disadvantages include lack of control, difficulty capturing the complexity of
behavior, observer fatigue and bias, subjects possibly altering their behavior as a
result of being observed, difficulty in replication, and the inability to provide an
explanation.
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2.
Self-reports: Interviews, surveys and questionnaires gather subjects’ responses to a set
of questions.
a. The ability to gather a lot of information with relative ease and speed is a major
advantage of this method.
b. The validity of self-report data is affected by the quality of the questions being
asked and the honesty of the subjects.
i. Responses may be distorted by faulty memory.
ii. Subjects may try to present themselves in a favorable light (social
desirability bias) or provide responses that reflect their interpretation
of what is expected of them (demand characteristics).
3. The case-study method involves an in-depth investigation of one individual.
a. Case studies gather a great deal of information case and allow for the generation
of additional hypotheses to be tested later.
b. The disadvantages identified for self-report data can be applied to the case
study. Researcher bias and the inability to generalize findings are additional
disadvantages.
D. Research Design
1. The way a research project is set up and organized is referred to as research design.
2. Nondevelopmental research (general research designs) looks for relationships among
variables without regard to age.
a. A correlational study seeks to determine relationship between two or more
variables and to describe its nature and strength.
i. A positive correlation indicates that the two variables vary in the same
direction (one increases, the other increases); whereas a negative
correlation indicates an inverse relationship (one increases, the other
decreases).
ii. The degree of relationship is expressed statistically as a correlation
coefficient which vary from zero (no relationship) to + 1.0 (perfect
relationship).
iii. Correlational studies allow us to make predictions and to study things
that could not otherwise be studied because of ethics. A major
disadvantage of correlational research is that it does not prove causeand-effect.
b. An experimental study creates an artificial setting in which subjects are
exposed to a specific treatment (independent variable) and their responses
(dependent variable) are recorded to determine if a causal relationship exists
between the two.
i. The experimental group is exposed to the treatment and compared to
the control group (no treatment).
ii. Double blind studies are conducted to control for experimenter bias
and placebo effect.
iii. Controlling for extraneous variables requires both groups being
treated the same to avoid confounding of variables.
iv. The experiment allows researchers to establish cause-and-effect
relationships and can be replicated.
v. Disadvantages of the experiment include the artificial nature of the
laboratory and ethical considerations.
vi. Quasi-or natural experiments allow researchers to study groups that
have been influenced by variables that could not be studied ethically in
a laboratory.
3. Developmental research designs look for relationships between chronological age and
another variable.
a. The outcome of developmental studies may be affected by age, cohort, and timeof-measurement effect.
i. Age effects represent inherent differences in individual behavior (i.e.
physiological development).
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ii.
b.
c.
d.
e.
Cohort effects represent sociohistorical influences on the behavior of
people born during a particular period.
iii. Time-of-measurement effect represents influences in the environment
between and during the time behavior is measured.
Cross–sectional studies compare different age cohorts at one point in time to
determine differences in a specific behavior.
i. Cross – sectional – studies are easier to manage, are time efficient, and
hold constant time-of-measurement effect.
ii. The confounding of age and cohort effect is a major disadvantage.
Longitudinal studies follow one group of same-aged subjects over a long
period of time.
i. Longitudinal studies control for cohort effect.
ii. These studies are time consuming, expensive, and subject attrition rates
may bias results.
In time-lag studies, same-age groups are observed at different times.
i. Cohort and time-of- measurement effect may be confounded.
ii. These studies are expensive, time consuming, and only one age is
studied.
Sequential designs combine the strengths and minimize the weaknesses of
cross-sectional, longitudinal, and time-lag studies.
V. Special Considerations and Limitations in the Research
A. Ethical constraints have been established to insure respect of the dignity of human subjects and to
protect them from harm.
B. Ageism, which refers to stereotyping, prejudice, and discrimination based on age, has the potential
to influence research.
C. Cultural, racial, socioeconomic, and gender bias are important considerations in psychological
research.
Discussion and Activity Suggestions
Values Walk –A First Day Activity
This ice breaker introduces students to each other and the subject matter in a non-threatening way that gets all
students participating. Prior to the first class, make one large sign for each of the following: agree, strongly agree,
disagree, and strongly disagree. Place one sign on each of the classroom walls before students arrive. Have students
push desks to the walls and come to the center of the room. Tell students that you will be presenting several values
statements related to adult development and aging topics that will be discussed throughout the course and are
interested in knowing where they “stand” on each topic. When a statement is placed on the overhead projector or
computer screen, they are to move to the section of the room that “best” represents their position in relation to this
issue. Before the first statement goes up, ask students to walk around and learn as many names as possible in a
minute. Place the first statement on the overhead or computer screen and ask students to take their positions. Once
students are in place, ask them to explain their position. Students are asked to state their name before beginning,
“My name is Pat, and I strongly agree because …” While disagreement is encouraged, instruct students that no one
is allowed to attack another student’s statements and that only one person will be allowed to speak at a time. Those
wishing to speak must raise their hands, and you will recognize each speaker. Be sure to alternate between sections
of the room (first agree, then disagree, etc.) and try to get as many students as you can involved in responding.
Students can physically change their position at any time during the discussion. After a couple of minutes, the
process is repeated (a minute to meet and another statement). Do as many as you can, but allow at least 20 minutes
to discuss and evaluate the activity. Distribute the evaluation form (Handout Master 1-1) and give students a couple
of minutes to write responses anonymously. Collect them and pass them out so that no student gets his/her
responses. Go around the room and have each student read the first response on the sheet. Repeat until all the
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