Chapter 2Models of Development:

Nature and Nurture in Adulthood

“How old would you be if you didn’t know how old you was?”

Satchel Paige 1906-1982

Key concepts in the study of the lifespanKey concepts in the study of the lifespan

• Life Span Perspective (LSP) views life from conception (& childhood) through old age and death– Contextual influences include sex, race,

ethnicity, social class, religion, and culture

Gerontology is an interdisciplinary approach to understanding aging

Gerontology is an interdisciplinary approach to understanding aging

Key concepts in the study of the lifespanKey concepts in the study of the lifespan

• Life span change is a function of nature and nurture– Organismic model emphasizes heredity (nature)– Mechanistic model emphasizes outside forces (nurture)

Developmental science looks at multiple factors in development

• Niche-pickingNiche-picking: genetic and environmental factors work together to influence the direction of a child’s life

• Interactionist model:Interactionist model: 3 contributors to development– 1. genetics– 2. environment– 3. individuals actively shape their own development

Key concepts in the study of the lifespanKey concepts in the study of the lifespan

Plasticity: one’s capabilities & potential are not fixed

Reciprocity principleReciprocity principle: people influence and are influenced by the events in their lives

From genome to protein

• Genome: complete set of instructions for “building” all the cells that make up an organism

• Deoxyribonucleic acid (DNA): a molecule capable of replicating itself that encodes information needed to produce proteins

Biological models of developmentBiological models of development

From genome to protein

Mutations may lead the genes to produce abnormal proteins

Mutations may lead the genes to produce abnormal proteins

• Gene: a functional unit of a DNA molecule carrying as particular set of instructions for producing a specific protein

• Chromosome: a distinct, physically separate unit of coiled threads of DNA and associated protein molecules

Genome-Wide Linkage Study Researchers study genomes of families with specific traits or disorders

Genome-Wide Association Study (GWAS)Researchers scan the entire genome of a large number of people

Two types of genetic studiesTwo types of genetic studies

Single Nucleotide Polymorphisms (SNPs)

• A SNP is a genetic variation that can occur in a person’s DNA sequence.

• A single base is replaced by any of the other three bases.

• Many researchers believe that some SNPs may predispose people to resistance to disease or a longer lifespan.

Programmed Aging Theories

• These theories propose that aging and death are built into the hard-wiring (and genetic code) of all species.

• Replicative senescence: the loss of the ability of cells to reproduce

According to the telomere theory, telomere theory, each cell replication reduces the length of telomeres until the chromosome’s tips are no longer protected.

Is FOXO3AFOXO3A the newest longevity gene?

Certain SNPs in the FOXO3A gene are associated with longevity

• The Gompertz Function plots the relationship between age and death rates for a given species

• It demonstrates that the mortality rate increases in a geometric progression with age.

Source: Sacher, G. A. (1977). Life table modification and life prolongation. In C. E. Finch & L. Hayflick (Eds.), Handbook of the biology of aging (pp.582–638). New York: Van Nostrand Reinhold.

White-footed mouse

Cotton rat

Random Error Theories of Aging:

• These theories are based on the assumption that aging reflects unplanned changes in an organism over time

• Wear and tear theory of aging: a body, like a car, acquires more and more damage as it is exposed to daily use

Cross-linking theory proposes that aging causes deleterious changes in cells of the body that make up much of the body’s connective tissue, including the skin, tendons, muscles, and cartilage.

Collagen: the fibrous protein that makes up about one-fourth of all bodily proteins.

In cross-linking,cross-linking, the strands of the collagen molecule (left) start to become intertwined, causing the molecules to become increasingly more rigid and smaller.

Free Radical Theory

• Free radicals: Unstable oxygen molecules produced when cells create energy

• They seek out and bind to other molecules

• The attacked molecule then loses its functioning

• Antioxidants can fend them off

• Free radical theory states that the cause of aging is the increased activity of unstable oxygen molecules that bond to other molecules and compromise the cell’s functioning.

Autoimmune Theory of Aging

• This theory proposes that aging is due to faulty immune system functioning in which the immune system attacks the body’s own cells.

• This theory proposes that mutations in mitochondrial DNA acquired over the organism’s lifetime lead to malfunctioning of the body’s cells.

Error Catastrophe Theory of Aging

Bronfenbrenner’s ecological perspective

Urie Bronfenbrenner (1917-2005)

Development is Development is affected by affected by processes at processes at multiple levelsmultiple levels

Sociocultural models of developmentSociocultural models of development

Bronfenbrenner’s ecological perspectiveMicrosystem: the setting in which people have their daily interactions and which therefore have the most direct impact on their livesExosystem: includes the environments that people do not closely experience on a regular basis but that impact them neverthelessMacrosystem: includes larger social institutions ranging from a country’s economy to its laws and social normsMesosystem: realm of the environment in which interactions take place among two or more microsystemsChronosystem: changes that take place over time

Sociocultural models of developmentSociocultural models of development

Whitehall IIWhitehall II investigated influence of social class on healthHere, men and women in lower employment grade occupations had lower physical functioning scores.

Whitehall IIWhitehall II investigated influence of social class on healthHere, men and women in lower employment grade occupations had lower physical functioning scores.

Source: Marmot, M., & Brunner, E. (2005). Cohort profile: the Whitehall II study. International Journal of Epidemiology, 34, 251–260 by permission of Oxford University Press.

Life course perspective:Life course perspective: norms, roles, and attitudes about age help to shape the person’s life

Child Teen Young adult

Midlife adult

Older adult

Social clock: Social clock: the expectations for the ages at which a society associates major life events

Contrasting life course theories

Activity theoryOlder adults are better adjusted when they remain involved in their social roles

Disengagement theoryThe normal course of life is for older adults to loosen their social ties

Continuity theoryThe individual’s personality determines whether activity or disengagement is optimal

Ageism Ageism is a form of stereotyping or discrimination based on age that can have many negative consequences

Copyright © 2014 John Wiley & Sons, Inc. All rights reserved.

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Where does ageism come Where does ageism come from?from?• Terror management theory: seeing older adults remind us of our mortality• Modernization hypothesis: industrialization led older adults to become obsolete• Multiple jeopardy hypothesis: ageism is another “ism”

Why aren’t more older adults negatively affected by ageism?Age-as-leveler: Older adults become regarded as targets regardless of prior statusInoculation hypothesis: older adults, especially women and minorities, become immune to ageism

Why aren’t more older adults negatively affected by ageism?Age-as-leveler: Older adults become regarded as targets regardless of prior statusInoculation hypothesis: older adults, especially women and minorities, become immune to ageism

Piaget’s Cognitive-Developmental Theory:

Schemas, Assimilation & Accommodation in less than 2 minutes--Link to Video

Jean Piaget (1896-1980)

Schemas: Mental structures we use to understand the world

“Toy cars”

Piaget’s Cognitive-Developmental Theory

“Toy car!”

Accommodation: Occurs when one changes a schema in response to new information about the world

E.g., Expand categories of 4-wheeled toys—cars AND trucks.

“Toy trucks”

• 4 stages of cognitive development

• Each stage represents a time of equilibrium, when assimilation and accommodation are perfectly balanced.

Identity process theoryIdentity process theory• Susan Krauss Whitbourne• Identity continues to change in adulthood in a dynamic manner• Identity: a set of schemas one holds about oneself• Identity assimilation: tendency to interpret new experiences in

terms of person’s existing identity• Identity accommodation: a change in identity in response to

experiences that challenge one’s current view of him/herself• Identity balance: equilibrium that occurs when people tend to

view themselves consistently but can make changes when called for by their experiences

• Self efficacy: a person’s feeling of competence at a particular task

• Individuals realize they are getting older through a stepwise process as aging-related changes or illness occur

• Identity accommodation tends to have more negative effects on the individual than does identity assimilation or balance.

Multiple threshold modelMultiple threshold model

Selective optimization with compensation model (SOC)

Adults attempt to preserve and maximize the abilities that are of central importance and put less effort into maintaining those that are not.

E.g., When aerobic exercise becomes too strenuous, people might substitute tai chi.

Erikson’s Psychosocial Theory of Development

• Erik Erikson (1902-1994)• At certain points in life, a

person’s biological, psychological, and social changes come together to influence personality

Possible Outcomes of Psychosocial Stages

Your Life Events

• For each of the age ranges listed, write down a memory from that time period. If you do not remember or have not yet reached a particular age range, write down one event that you believe would be important for the age range in question.

• 0-1• 2-3• 4-5 • 6-12 • 13-20• 21-39• 40-64• 65+

WEEKLY WORK: Group Project“Events During 8 Stages of Life”

• Form groups of four.

• Discuss the ideas of each group member, stage by stage.

• Based on the ideas provided by all of the group members, pick one example that the group decides best illustrates each stage of psychosocial development.

– For each of one of your 8 chosen examples, note the following:• psychosocial crisis (e.g., Basic Trust versus Mistrust)• significant relationship(s) involved• basic strength acquired• outcome (or anticipated outcome)

• Your group will then make a brief presentation to the class, providing the examples you chose for each of the 8 stages of psychosocial development and explaining how your examples fit Erikson’s psychosocial model.