Developmental psychology studies patterns of growth and change throughout life. Two key research methods are cross-sectional research, which compares age groups, and longitudinal research, which studies individuals over many years. Erik Erikson's influential theory of psychosocial development proposed that people progress through eight stages of developing trust, autonomy, initiative, identity and integrity. Successful completion of the challenges in each stage leads to healthy development.

1. Development
Intro +
Erikson

2. Developmental
Psychology:
The branch of psychology
that studies the patterns of
growth and change that
occur throughout life.

3. Cross-Sectional Research
A frequently used method to study development is
cross-sectional research: comparing people of different
ages at the same point in their lives. This is done in
order to discover differences between age groups and
similarities within the same age group.
Researchers
compare groups of 5
year olds, 15 year
olds, 25 year olds
(and so on) in order
to identify how they
are similar at certain
times in their lives.

4. Longitudinal Research
Another method of studying development is longitudinal
research: studying the behavior and changes of an
individual as they age.
Individuals are
studied many
times throughout
their lives at
benchmark ages.
Researchers note
differences in
behavior as the
participants get
older.

5. We study human
development in order to
answer the question:
“How did I become ME?”

6. Erikson’s Theory of
Psychosocial Development
Erik Erikson (1902-1994) was a
German/American psychologist
who was famous for his
developmental theory and for
coining the phrase “identity crisis.”
His theory sought to explain
human development by
categorizing our behaviors and
major changes into 8 stages. In
each stage, there is a crisis, or
challenge that humans must
overcome.

7. Stage 1: Trust vs. Mistrust
Age: 0-18 months.
Crisis: Infants develop feelings of trust, or a lack of trust. If adults
meet the needs of the baby (nourishment, attachment, attention), the
baby develops trust. If adults are inconsistent providers or the baby
experiences unpleasant interactions, it develops mistrust.

8. Stage 2: Autonomy vs. Shame and Doubt
Age: 18 months - 3 years.
Crisis: Toddlers develop independence and autonomy if exploration
and freedom are encouraged, or shame and self-doubt if they are
overprotected and freedom is too restricted. Parents must provide
the right amount of control: if they provide too much, children can’t
learn to assert themselves and develop their own sense of control
over the environment. If parents do not provide enough control,
children become demanding, spoiled, or controlling.

9. Stage 3: Initiative vs. Guilt
Age: 3-6 years.
Crisis: Children experience conflict between making independent
actions, and the negative consequences that sometimes result from
those actions. Children begin to learn that they are independent
individuals who control their own behavioral choices. If parents
respond well when their children make mistakes, it helps resolve the
experience of guilt the children will be facing.

10. Stage 4: Industry vs. Inferiority
Age: 6-12 years.
Crisis: Older children may develop positive social interactions with
others, or may feel inadequate and become less social. In this stage,
children become more competent in all areas from social interactions
to academic skills. Experiencing difficulty in this process leads to
feelings of failure.

11. Stage 5: Identity vs. Role Confusion
Age: 12-20 years (adolescence).
Crisis: Teenagers develop awareness of self (who they are and what
their purpose is) and knowledge of their role in the world, or, they
feel “lost” and unsure of who they are. In this stage, reliance on adults
becomes increasingly less.

12. Stage 6: Intimacy vs. Isolation
Age: 21-35 years (Early Adulthood).
Crisis: Young adults focus on forming close relationships with others.
Difficulties during this stage result in feelings of loneliness and even
fear of relationships themselves. Successful resolution of this crisis
results in formation of relationships that are intimate on a physical,
intellectual, and emotional level.

13. Stage 7: Generativity vs. Stagnation
Age: 35-60 years (Middle Adulthood).
Crisis: Generativity means the ability to contribute to one’s family,
community, work, and society in a positive way, and to assist the
younger generation. Success in this stage results in feelings of self-
worth and connectedness with the world. Difficulties in this stage
result in feeling insignificant, and the feeling that your activities are
trivial, stagnant, or not helping future generations.

14. Stage 8: Integrity vs. Despair
Age: 60+ years (Late Adulthood).
Crisis: In late adulthood, we review life’s accomplishments and
failures. Either we form a sense of satisfaction and unity, or we form a
sense of regret over opportunities that we lost and things we never
got the chance to do. Adults continue to work of forming a feeling of
peace with their lives until death.

15. Stages: Summary
Overcoming the
obstacles
presented in
each stage leads
to positive
developmental
outcomes.
Failure to
overcome
difficulties can
lead to
unfavorable
developmental
outcomes.