2. Theories of Aging:
attempt to explain the phenomenon of
aging as it occurs over the lifespan
– aging is viewed as a total process that begins
at conception
– senescence: a change in the behavior of an
organism with age leading to a decreased
power of survival and adjustment
3. Theories of Aging: Types
Biologic
Sociologic
Psychologic
Moral/Spiritual
4. Biologic Theories:
Concerned with answering basic questions
regarding the physiological processes that
occur in all living organisms as they
chronologically age
5. Foci of Biologic Theories
Explanations of:
– 1) deleterious effects leading to decreasing
function of the organism
– 2) gradually occurring age-related changes that
are progressive over time
– 3) intrinsic changes that can affect all member
of a species because of chronologic age
6. ALSO:
– all organs in any one organism do not age at
the same rate
– any single organ does not necessarily age at
the same rate in difference individuals of the
same species
7. Biologic Theories: Divisions
Stochastic: Explain aging as events that
occur randomly and accumulate over time
Nonstochastic: View aging as certain
predetermined, timed phenomena
9. Error Theory
Originally proposed in 1963
Basis: 1)errors can occur in the
transcription in any step of the protein
synthesis of DNA
– 2) error causes the reproduction of an enzyme
or protein that is not an exact copy
– 3) As transcription errors to occur, the end
product would not even resemble the original
cell, thereby compromising its functional
ability
10. Error, cont’d
More recently the theory has not been
supported by research
– not all aged cells contain altered or
misspecified proteins
– nor is aging automatically or necessarily
accelerated if misspecified proteins or
enzymes are introduced into a cell
11. Free Radical Theory
Free radicals are byproducts of
metabolism--can increase as a result of
environmental pollutants
When they accumulate, they damage cell
membrane, decreasing its efficiency
The body produces antioxidants that
scavenge the free radicals
12. Free Rads, cont’d
In animal studies, administration of
antioxidants postpones the appearance of
diseases such as cardiovascular disease and
CA
Free radicals are also implicated in the
development of plaques associated with
Alzheimer’s
13. Cross-Linkage Theory
Some proteins in the body become cross-
linked, thereby not allowing for normal
metabolic activities
Waste products accumulate
Result: tissues do not function at optimal
efficiency
14. C-L Theory, cont’d
Some research supports a combination of
exercise and dietary restrictions in helping
to inhibit the cross-linkage process
15. Wear & Tear Theory
Proposed first in 1882
Cells simply wear out over time because of
continued use--rather like a machine
Would seem to be refuted by the fact that
exercise in OA’s actually makes them
MORE functional, not less
17. Programmed (Hayflick Limit)
Theory
Based on lab experiments on fetal
fibroblastic cells and their reproductive
capabilities in 1961
Cells can only reproduce themselves a
limited number of times.
Life expectancies are seen as
preprogrammed within a species-specific
range
18. Immunity Theory
Immunosenescence: Age-related functional
diminution of the immune system
Lower rate of T-lymphocyte (“killer cells”)
proliferation in response to a stimulus
& therefore a decrease in the body’s
defense against foreign pathogens
19. Immunity, cont’d
Change include a decrease in humoral
immune response, often predisposing older
adults to:
– 1)decreased resistance to a tumor cell
challenge and the development of cancer
– 2) decreased ability to initiate the immune
process and mobilize defenses in aggressively
attaching pathogens
– 3) increased susceptibility to auto-immune
diseases
21. Neuroendocrine Control
“…examines the interrelated role of the
neurologic and endocrine systems over the
life-span of an individual”. (p. 24)
there is a decline, or even cessation, in
many of the components of the
neuroendocrine system over the lifespan
22. Neuro, cont’d
Research has shown
– 1) the female reproductive system is controlled
by the hypothalamus. What are the
mechanisms that trigger changes?
– 2) adrenal glands’ DHEA hormone
– 3) melatonin (from pineal gland)--a regulator
of biologic rhythms and a powerful
antioxidant. Declines sharply from just after
puberty
23. Metobolic Theory of Aging
(Caloric Restriction)
“…proposes that all organisms have a
finite amount of metabolic lifetime and that
organisms with a higher metabolic rate
have a shorter lifespan”. (p. 24)
Rodent-based research has demonstrated
that caloric restriction increases the
lifespan and delays the onset of age-
dependent diseases
24. DNA-Related Research
Major Developments:
– Mapping the human genome (“…there may be
as many as 200 genes responsible for
contolling aging in humans”)
– Discovery of telomeres
26. Changing FOCUS of Sociological
considerations of aging:
– 60’s focus on losses and adaptation to them
– 70’s broader global, societal, and structural
factors influencing lives of OA’s
– 80’s-90’s exploration of interrelationships
between OA’s and their physical, political,
environmental & socioeconomic mileau
27. Disengagement Theory
Cumming & Henry--1961
Aging seen as a developmental task in and
of itself, with its own norms & appropriate
patterns of behavior
“appropriate” behavior patterns involved a
mutual agreement between OA’s and
society on a reciprocal withdrawal.
No longer supported
28. Activity Theory (Developmental
Task Theory)
Havighurst, Neugarten, Tobin ~1963
“Activity is viewed by this theory as
necessary to maintain a person’s life
satisfaction and a positive self-concept”.
(p.27)
29. Activity, cont’d
Theory based on assumptions:
– 1) it’s better to be active than inactive
– 2) it is better to be happy than unhappy
– 3) an older individual is the best judge of his
or her own success in achieving the first two
assumptions
30. Continuity Theory
How a person has been throughout life is
how that person will continue through the
remainder of life
Old age is not a separate phase of life, but
rather a continuation and thus an integral
component
31. Age Stratification Theory
Riley--1985
Society consists of groups of cohorts that
age collectively
The people & Roles in these cohorts
change & influence each other, as does
society at large
Thus, there is a high degree of
interdependence between older adults &
society
32. Person-Environment Fit Theory
Lawton, 1982
Individuals have personal competencies
that assist in dealing with the environment:
– ego strength
– level of motor skills
– individual biologic health
– cognitive & sensory-perceptual capacities
33. P-E Fit, cont’d
As a person ages, there may be changes in
competencies & these changes alter the
ability to interrelate with the environment
Significant implications in a society that is
characterized by constantly changing
technology
34. PSYCHOLOGIC THEORIES
OF AGING
Maslow’s Hierarchy of Human Needs
Jung’s Theory of Individualism
Erikson’s Eight Stages of Life
Peck’s Expansion of Erikson’s Theory
Selective Optimization with Compensation
35. Maslow’s Hierarchy of Human
Needs
Maslow--1954
“…each individual has an innate internal
hierarchy of needs that motivates all
human behaviors”. (p. 29
depicted as a pyramid; the ideal is to
achieve self-actualization, having met all
the “lower” level needs successful
36. “Maslow’s fully developed, self-actualized
person displays high levels of all of the
following characteristics: perception of
reality; acceptance of self, others, and
nature; spontaneity; problem-solving
ability; self-direction; detachment and the
desire for primacy; freshness of peak
experiences; identification with other
human beings;…….
37. …satisfying and changing relationships
with other people; a democratic character
structure; creativity; and a sense of values.
Only about 1% of us are truly ideal self-
actualized persons
38. Jung’s Theory of Individualism
Carl Jung--1960
origins are Freudian
Self-realization is the goal of personality
development
as individual ages, each is capable of
transforming into a more spiritual being
39. Erikson’s Eight Stages of Life
1993
Stages throughout the life course. Each
represents a crisis to be resolved.
For OA’s:
– 40 to 65 (middle adulthood): generativity
versus self-absorption or stagnation
– 65 to death (older adulthood): ego integrity
versus despair
40. Erikson, cont’d
“Self-absorbed adults will be preoccupied
with their personal well-being and material
gains. Preoccupation with self leads to
stagnation of life”
“Unsuccessful resolution of the last crisis
may result in a sense of despair in which
individuals view life as a series of
misfortunes, disappointments, and
failures”. (p.30)
41. Peck’s Expansion of Erikson’s
Theory
Erikson’s last two stages are expanded to 7
The final three of the developmental tasks
for old age:
– ego differentiation versus work role
preoccupation
– body transcendence versus body
preoccupation
– ego transcendence versus ego preoccupation
43. Selective Optimization, cont’d
3 Interacting Elements:
– selection: increasing restriction of one’s life to
fewer domains of functioning
– optimization: people engage in behaviors to
enrich their lives
– compensation:developing suitable, alternative
adaptations