Chapter 2:

The Science

of Life-Span

Development

McGraw-Hill © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

Theories

of

Development

• All scientific knowledge comes from scientific

investigation – a four-step process

– Identify a problem to be studied

– Collect data or research information

– Analyze the data

– Draw conclusions

• Diverse but complimentary theories are used

for explaining life-span development:

– Psychoanalytic theories

– Cognitive theories

– Ethological theories

– Ecological theories

Psychoanalytic Theories:

• Freud’s Psychosexual Theory

– Personality has 3 parts

– There are 5 stages of psychosexual development

– Oedipus complex allows child to identify with

same-sex parent

– Fixation is an unresolved conflict during a stage

of development

• Today’s focus is more on cultural experiences and

less on sexual instincts

Phallic

Stage

Child’s

pleasure focuses on

genitals

Figure 2.1

Latency

Stage

Child

represses sexual interest

and develops social and intellectual

skills

Anal Stage

Child’s

pleasure focuses on

anus

Genital

Stage

A time of

sexual reawakening;

source of sexual

pleasure becomes someone

outside of the family

Oral Stage

Infant’s pleasure

centers on mouth

Freudian Stages

6 yrs to puberty

Birth to 1½ yrs

1½ to 3 yrs

Puberty onward

3 to 6 years

• Erikson’s Psychosocial Theory:

– There are 8 stages of psychosocial development

– Each has a unique developmental task

– Developmental change occurs throughout life span

• Key points of psychoanalytic theories:

– Early experiences and family relationships are

very important to development

– Unconscious aspects of the mind are considered

– Personality is best seen as a developmental process

Erikson’s Stages Developmental Period Trust vs Mistrust Infancy (first year)

Autonomy vs shame & doubt

Infancy (1 to 3 years)

Initiative vs guilt Early childhood (3 to 5 years)

Industry vs inferiority Middle and late childhood

Identity vs identity confusion

Adolescence (10 to 20 years)

Intimacy vs isolation Early adulthood (20s, 30s)

Generativity vs stagnation

Middle adulthood (40s, 50s)

Integrity vs despair Late adulthood (60s onward)

Figure 2.2

Erikson’s Eight Life-Span Stages

Cognitive theories:

• Piaget’s cognitive developmental theory

– Stresses conscious mental processes

– Cognitive processes are influenced by

biological maturation

– Four stages of cognitive development

in children

– Assimilation and accommodation underlie

how children understand the world, adapt

to it, and organize their experiences

Preoperational Stage:

The child begins to represent the world with words and images. These words and images reflect increased symbolic thinking and go beyond the connection of sensory information and physical action.

Formal Operational Stage

The adolescent reasons in more abstract idealistic and logical ways.

Sensorimotor Stage:

The infant constructs an understanding of the world by coordinating sensory experiences with physical actions: progressing from reflexive, instinctual action at birth to the beginning of symbolic thought toward end of the stage.

Concrete Operational Stage:

The child can now reason logically about concrete events and classify objects into different sets.

Figure 2.3

11–15 years of age

through adulthood

Birth to 2 years of age

2 to 7 years of age

7 to 11 years of age

Piaget’s Four Stages of Cognitive Development

• Vygotsky’s sociocultural cognitive theory

– Children actively construct their knowledge

– Social interaction and culture guide cognitive

development

– Learning is based upon inventions of society

– Knowledge is created through interactions with

other people and objects in the culture

– Less skilled persons learn from the more skilled

• Information-processing theory

– Compares computers to the human mind

– Thinking is information processing

Information is taken into brain

Information gets processed, analyzed, and stored until use

OUTPUT INPUT

Information is used as basis of behaviors and interactions

Information-Processing Theory

math

history religion

geography

science

literature

Behavioral and social cognitive theories:

• Pavlov’s classical conditioning includes

conditioned and unconditioned responses

• Watson applies association and generalization

• Operant conditioning focuses on positive and

negative reinforcement

• Social cognitive theory focuses on observation

and imitation

• Ethological theory includes imprinting and

attachment

Classical

Conditioning

Generalization

Operant Conditioning

What are the reinforcements to achieve?

What happens when there are no controls or reinforcement?

Task: Learn to read

Environment Person

(cognitive)

Behavior

Bandura’s Social Cognitive Model

Figure 2.4

Bandura’s Modeling/Imitation

Child observes someone admired

Child imitates behavior

that seems rewarded

• Urie Bronfenbrenner’s ecological theory:

– Environmental factors influence development

– 5 environmental systems affect life-span

development

• Eclectic theoretical orientation:

– Selects features from other theories

– No one theory has all the answers

– Each theory can make a contribution to

understanding life-span development

Exosystem Mesosystems

Macrosystem

Family School & classroom

Religion & groups

Peer group

Chronosystem

School system

Political philosophy

Figure 2.5

Bronfenbrenner’s

Ecological Theory

of Development

Research

in

Life-Span

Development

• Types of research:

– Descriptive: observes and records

behavior

• Laboratory research

• Naturalistic observation

• Surveys and interviews

• Standardized tests

• Case studies

• Life-history records

• Physiological measures

Figure 2.8

0

25

5

30

15

10

20

Girls Boys

Percentage parent–child interactions in which the parent explained science concepts

Parents’ Explanations of Science to Sons and Daughters at a Science Museum

– Correlational research

• Measures relationships; not the same

as causation

– Experimental research

• Independent variable gets manipulated

• Dependent variable is the resulting change

• Experimental group is manipulated

• Control group serves as the “norm”

for comparison

Other factors, such as genetic

tendencies, poverty, and sociohistorical

circumstances Children’s lack of self-control

Permissive parenting

Children’s lack of self-control

Permissive parenting

Permissive parenting

Children’s lack of self-control

and

causes

both

cause

causes

Observed correlation: as permissive parenting increases, children’s self-control decreases

Figure 2.9

Possible Explanations for Correlational Data

Newborns’ breathing and sleeping patterns

Control group

(no aerobic exercise)

Participants randomly assigned to experimental and control groups

Dependent variable

Independent variable

Experimental group

(aerobic exercise)

Principles of Experimental Research

Figure 2.10

Group 2 Time playing video

games: 6 hours

each day

More aggressive

and antisocial

More playful

and sociable

Time playing video

games: 2 hours

each day

Group 1

• Time-span research

– Focus on the relation of age to some other

variable across the life span (e.g., memory)

– Cross-sectional approach compares different

age groups at one time

– Longitudinal approach studies a group over a

period of time

– Sequential approach combines longitudinal

and cross-sectional approaches

– Cohort effects: due to time or era of birth but

not due to one’s actual age

Facing Up to

Research Challenges

• Conducting Ethical Research

– Informed consent: participants give informed

consent and participation is voluntary

– Confidentiality of participants’ information

– Participants’ rights will be observed

– Debriefing after the experiment

– Deception: researchers ensure any deception

will not harm the participants

• Minimize bias:

– Gender bias is based on preconceived ideas

about the abilities and differences between

men and women; research affects how people

think about men and women

– Cultural and ethnic bias

• Life-span research needs to include more

diverse groups of people

• Avoid ethnic gloss in research

• Being a Wise Consumer of Information – Media only publishes parts of research when

of public interest

– All information for public consumption may be

• Oversimplified, condensed with few details

• Distorted or exaggerated

– People must consider information carefully

• Separate group from individual outcomes

• Do not overgeneralize from small sample

• Look for additional information on a study

• Do not attribute causes when none exist

• Evaluate the source of information

The End