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Chapter 1 An Introduction to Life Span Development
What is lifespan development?
The field of study that examines the patterns of growth, change, and stability in behavior that occur throughout the entire human life span.

Overall, lifespan developmentalists believe several things…

That the study of lifespan development should focus on human development
Principles that are universal to development
Cultural, racial, ethnic differences in development
The development of individual traits and characteristics
That development is a lifelong, continuing process
That development occurs through change and growth in addition to stability, consistency, and continuity
Developmentalists often focus on different topics…
Physical Development
The body’s physical makeup, including the brain, nervous system, muscles, and senses, and the need for food, drink, and sleep
Malnutrition, declining athletic performance
“How does malnutrition affect the growth of children?”
“How do athletes’ physical performance decline during adulthood?”

Topical Areas Studied by Developmentalists
Cognitive Development
Involves the ways that growth and change in intellectual capabilities influence a person’s behavior
Learning, memory, problem-solving skills, and intelligence across the lifespan
“How do people explain their academic successes and failures?”
“Can a person who experiences a traumatic event as a young child remember it when he or she becomes an adult?”

Topical Areas Studied by Developmentalists
Personality Development
Involves the ways that the enduring characteristics that differentiate one person from another remain stable or change over the life span
“Are there stable, enduring personality traits that persist throughout the lifespan?”

Topical Areas, continued
Social Development
Involves the way in which an individual’s interactions and social relationships grow, change, and remain stable over the course of life
“How do poverty, racism, and divorce affect development?”
The lifespan is usually divided into broad (albeit arbitrary) age ranges.
Age Ranges of the Life Span
Prenatal - conception to birth
Infancy and toddlerhood - birth to age 3
Preschool - ages 3 to 6
Middle childhood - ages 6 to 12
Adolescence - ages 12 to 20
Young adulthood - ages 20 to 40
Middle adulthood - ages 40 to 60
Late adulthood - age 60 to death
Age Ranges, cont.
An important thing to remember about these age ranges is that they are social constructions--shared notions that are widely accepted in our culture.
People mature at different rates and reach developmental milestones at different points
Environmental factors, including culture, play a role in determining when events occur
Age ranges are only averages, and some people will be above or below.
The Context of Development
The bioecological approach (Bronfenbrenner) - suggests that different environmental levels simultaneously influence individuals
Four major levels:
Microsystem (everyday immediate environment): home, caregiver/parent, friends, teachers
Mesosystem (connects parts of the microsystem): parents linked to children, students to teachers, friends to friends, bosses to employees

Bronfenbrenner’s Ecological Approach, cont.
3) Exosystem (represents broader influences): local government, the community, schools, places of worship, local media
4) Macrosystem (represents larger cultural influences): society in general, federal government, religious and political value systems
5) Chronosystem (underlies all systems): the passage of time and historical events affects development

Advantages to the Ecological Approach
It emphasizes the interconnectedness of the influences on development.
It illustrates that influences are multidimensional.
It stresses the importance of broad cultural factors that affect development.
Developmental Diversity
Major factors influencing developmental include cultural, ethnic, racial, socioeconomic, and gender differences.
Terms have been used inappropriately—”race” is a biological concept, whereas “ethnic group” and “ethnicity” are broader terms referring to cultural background, nationality, religion, and language.
How do these factors impact the different parts of the ecosystem?
Other Influences on Development
Each person’s COHORT
The group of people born at around the same time and same place

History-Graded Influences
Biological and environmental influences associated with a particular historical movement
September 11, 2001 terrorist attacks; December 2004 tsunami in Indian Ocean

Age-Graded Influences
Biological and environmental influences that are similar for individuals in a specific age group, regardless of when or where they were raised
Puberty, menopause, entry into school

Sociocultural-Graded Influences
The impact of social and cultural factors present at a specific time for a specific individual, depending on unique variables such as ethnicity, social class, subcultural membership
Affluent childhood vs. living in poverty
Other Influences on Development
Non-normative Life Events
Specific, atypical events that occur in a particular person’s life at a time when they do not happen to most people
Cancer as a teen, auto accident
Key Issues in Lifespan Development
Continuous vs. Discontinuous Change
Continuous change
Gradual development in which achievements at one level build on those of previous levels
Changes achieved are a matter of degree, not kind
Discontinuous change
Development that occurs in distinct steps or stages
Changes achieved are qualitatively different that behavior at earlier stages
What do most developmental psychologists believe on this issue?
Some development is continuous, and some is discontinuous.
Critical Periods
A critical period is a specific time during development when an event has its greatest consequences (interference with critical periods thought to interfere with development, often permanently)
Language development, exposure to disease
NOW…The concept of a sensitive period is favored--
A sensitive period is a point in development when an individual is especially susceptible to certain stimuli, BUT the absence of those stimuli does not always produce irreversible consequences.
Key Issues in Lifespan Development
A focus on particular periods vs. lifespan approaches
Early developmentalists focused on “infancy” & “adolescence.”
Today the entire lifespan is seen as important for several reasons:
Growth and change are continuous throughout life.
Each age has reciprocal influences on other ages.
Key Issues in Lifespan Development
Nature vs. Nurture
Nature refers to inherited traits, abilities, and capacities; includes maturation
Nurture refers to the environmental influences that shape behavior
Developmentalists today believe that behavior is the result of nature and nurture combined.
Theoretical Perspectives
Theories are explanations and predictions that provide a framework for understanding relationships

We will consider 3 major theoretical perspectives used in lifespan development:
psychodynamic cognitive (behavioral)
Psychodynamic Perspective (Freud, Erikson)
Based on the view that behavior is motivated by unconscious/inner forces, memories, and conflicts (over which a person has little control or awareness).
Most closely associated with Freud.
Freud’s (1856-1839) Psychoanalytic Theory suggests that unconscious forces act to determine personality and behavior.
Freud also explored ways in which personality developed during childhood.
Psychosexual development theory
--series of stages that children pass through
--pleasure or gratification is focused particular biological function or body part (recall that the id operates on the pleasure principle)
5 main stages
1) oral (birth to 12-18 months)
2) anal (12-18 months to 3 years)
3) phallic (3 to 5-6 years)
4) latency (5-6 years to adolescence)
5) genital (adolescence to adulthood)

Erikson’s Psychosocial Theory
Each stage emerges as a fixed pattern that is similar for all people.
Each stage presents a crisis or conflict that each individual must address sufficiently at a particular stage.
No crisis is ever fully resolved, making life complicated.
UNLIKE FREUD, Erickson believed that development continued throughout the lifespan.
Behavioral Perspective (Skinner, Watson, Bandura)
Based on the idea that the keys to understanding development are observable behavior and outside environmental stimuli.
Behaviorists reject the idea that people universally pass through a series of stages.
They view development as occurring because of continuous exposure to specific factors in the environment – i.e., through learning.

Behavioral Perspectives, cont.
Social-Cognitive Learning Theory (Bandura)
Emphasizes learning by observation of another person (a model).
Social-cognitive theory DIFFERS from classical and operant conditioning by taking mental activity into consideration (thoughts, expectations).

Cognitive Perspective
Focuses on the processes that allow people to know, understand, and think about the world.
Piaget’s theory of cognitive development:
People pass in a fixed sequence through a series of universal stages of cognitive development.
In each stage, the quantity of information increases; the quality of knowledge and understanding increases too.

Piaget’s Theory of Cognitive Development
Human thinking is arranged into schemas
(organized mental patterns representing behavior and action).
The growth of children’s understanding of the world can be explained by two principles:
Assimilation (new experience incorporated into current way of thinking).
Accommodation (existing ways of thinking change as a result of new stimuli).
Assessing Piaget’s Theory
Thousands of studies provide support.
Some cognitive skills emerge earlier than Piaget suggested.
Some cognitive skills emerge according to a different timetable in non-Western countries.
Some adults never reach his highest level of thought (formal, logical).
Which Approach is Right?
Each emphasizes different aspects of development.
-Psychodynamic approach emphasizes emotions, motivational conflicts, and unconscious determinants of behavior.
-Behavioral approaches emphasize overt behavior.
-Cognitive approaches look more at what people think than what they do.

Research Methods
The SCIENTIFIC METHOD is the process of posing and answering questions using careful, controlled techniques that include systematic, orderly observation and the collection of data.
The scientific method involves the formulation of theories, broad explanations, and predictions about phenomena.
Research Methods, cont.
Theories allow developmentalists to summarize and organize prior observations and allow them to go beyond existing observations to draw deductions.
Theories are used to develop HYPOTHESES, predictions stated in a way that permits testing.

Research Strategies
Correlational Research
Seeks to identify whether an association or relationship between two factors exists.
The strength and direction of a relationship between two factors is represented by a mathematical score, called a correlation coefficient, that ranges from +1.0 (positive) to - 1.0 (negative).
A negative correlation informs us that as the value of one factor increases, the value of the other factor declines.
IMPORTANT: Finding that two variables are correlated with one another does NOT prove that one variable causes the other.

Types of Correlational Studies
Naturalistic Observation - observing naturally occurring behavior without intervention in the situation
Case Studies - intensive in-depth interviews with particular individual or small groups
Survey Research - ask questions of a group of people chosen to represent a larger population

Research Strategies, cont.
Experimental research: research designed to discover causal relationships between various factors
An EXPERIMENT is a process in which an investigator, called an experimenter, devises two different experiences for subjects or participants.
These two different experiences are called TREATMENTS.
The group receiving the treatment is known as the TREATMENT GROUP.
The CONTROL GROUP is the group that receives either no treatment or alternative treatment.

-The formation of treatment and control groups represents the INDEPENDENT VARIABLE, the variable that researchers manipulate in an experiment.

-In contrast, the DEPENDENT VARIABLE is the variable that researchers measure in an experiment and expect to change as a result of the experimental manipulation.

Experimental Research Settings
FIELD STUDY is a research investigation carried out in a naturally occurring setting.
LABORATORY STUDY is a research investigation conducted in a controlled setting explicitly designed to hold events constant.

Measuring Developmental Change

In LONGITUDINAL RESEARCH, the behavior of one or more individuals is measured as the subjects age.
-requires a tremendous investment of time
-possibility of participant attrition, or loss
-participants may become "test-wise"
Measuring Developmental Change, cont.
In CROSS-SECTIONAL RESEARCH, people of different ages are compared at the same point in time.
Differences may be due to cohort effects.
Selective dropout, where participants in some age groups are more likely to quit participating in the study than others
Unable to explain changes in individuals or groups

Measuring Developmental Change, cont.
In SEQUENTIAL STUDIES, researchers examine a number of different ages groups over several points in time.
-Combines longitudinal and cross-sectional methods