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5
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People age 65
and above are the most rapidly growing segment of the American population.
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17
Late
Adulthood:
Physical and
Cognitive
Development
Learning Outcomes
Discuss physical development in late adulthood
Compare programmed and cellular damage
theories of aging
Identify common health concerns associated
with late adulthood
Discuss cognitive development in late adulthood
TRUTH OR FICTION?
T F
Life expectancy has increased in the United
States over the past few decades.
T F
In Colonial America, aging was viewed so
positively that men often claimed to be older
than they actually were.
T F
Women lose the ability to reach orgasm after
the age of 70.
T F
Most older adults require institutional care.
T F
Substance abuse is rare in late adulthood.
An Agequake Is Comlife span (longevity) the
ing. People age 65 and
maximum amount of time a
above are the most rapperson can live under optimal
idly growing segment
conditions.
of the American population. So many people
are living longer that we are in the midst of a “graying
of America,” an aging of the population that is having
significant effects on many aspects of society.
Physical
Development
i
n 1900, only 1 person in 25 was over the
age of 65. Today, that figure has more than
tripled, to 1 in 8 of us. By mid-century, more
than 1 in 5 Americans will be 65 years of
age or older. By the year 2050, we expect to
see the percentage of Americans over the age of 75 to
double (Kawas & Brookmeyer, 2001). To put these
numbers in historical context, consider that through
virtually all of human history, until the beginning of
the nineteenth century, only a small fraction of humans
lived to the age of 50.
LONGEVITY AND LIFE EXPECTANCY
One’s life span, or longevity, is the length of time one
can live under the best of circumstances. The life span
of a species, including humans, depends on its genetic
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life expectancy the
amount of time a person can
actually be expected to live in
a given setting.
programming. With the
right genes and environment, and with the
good fortune to avoid
serious accidents or illnesses, people have a
life span of about 115 years.
One’s life expectancy refers to the number of years
a person in a given population group can actually
expect to live. The average European American child
TABLE 17.1
Life Expectancy at Birth
by Region,Country,
and Sex,2002
born 100 years ago in the United States could expect
to live 47 years. The average African American could
expect a shorter life of 35.5 years (Andersen & Taylor,
2009). Great strides have been made in increasing life
expectancy. High infant mortality rates due to diseases
such as German measles, smallpox, polio, and diphtheria contributed to the lower life expectancy rates of a
century ago. These diseases have been brought under
control or eradicated. Other major killers, including bacterial infections such as tuberculosis, are now
largely controlled by antibiotics. Factors that contribute to longevity include public health measures such
as safer water supplies, improved dietary habits, and
health care. Table 17.1 shows the life expectancy of
males and females born in 2002 in various regions and
countries of the world.
Life Expectancy in the “Eight Americas”
MALES
FEMALES
AFRICA
Mozambique
Egypt
49
32
68
51
32
73
ASIA
Afghanistan
China
India
Japan
South Korea
65
47
70
63
78
72
68
46
74
64
84
79
LATIN AMERICA
Brazil
Cuba
Jamaica
Mexico
68
67
74
74
69
74
75
79
78
75
EUROPE
France
Germany
Italy
Poland
Russia
Sweden
United Kingdom
69
75
75
76
70
62
77
76
76
83
81
82
78
73
83
81
NORTH AMERICA
Canada
United States
74
76
74
80
83
80
Today, the average American newborn can expect to
live to about 78 years, but there are important differences in life expectancy according to sex, race, geographic location, and health-related behavior (Ezzati
et al., 2008). As a matter of fact, some health professionals speak of “eight Americas,” which roughly correspond to areas of the country, but more importantly,
represent sex, ethnicity, and styles of life. For example,
the life expectancy for an Asian American woman living in an upscale county in “America One” is in the
upper 80s. The life expectancy for an African American
male living in an urban environment with a high risk
of homicide in “America Eight” is in the 60s (Murray
et al., 2006). In the case of groups that run a high risk
of homicide, the age at death of those who die in their
teens and twenties are averaged in with those who live
into their seventies, eighties, or nineties, bringing down
the overall average for the group.
T F
Life expectancy has increased in the United
States over the past few decades.
This is not true.
Figure 17.1 shows that although the life expectancy
in the United States has been generally rising, it declined
between 1983 and 1999 by a mean of 1.3 years in 11
U.S. counties for men and in 180 U.S. counties for
women. The counties with declines were concentrated
in Appalachia, along the Mississippi River, the Southeast, the southern Midwest, and Texas. Declines in life
expectancy were largely due to chronic illnesses such
as diabetes and lung cancer for women, and HIV/AIDS
and homicide for men. The behaviors associated with
Source: Adapted from U.S. Census Bureau. (2004, March 22). International Programs Center,
International Data Base. Global Population Profile: 2002, Table A-12.
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© argus/Shutterstock
The Eight
Americas
these deaths are smoking, overeating, risky sex, and
aggression.
Why the gap? For one thing, heart disease typically
develops later in life in women than in men, as estrogen
provides women some protection against heart disease.
Also, men are more likely to die from accidents, cirrhosis of the liver, strokes, suicide, homicide, HIV/AIDS,
and some forms of cancer. Many of these causes of
death reflect unhealthful habits that are more typical of
men, such as drinking, reckless behavior, and smoking.
Many men are also reluctant to have regular physical examinations or to talk over health problems with
their doctors. Many men avoid medical attention until
problems that could have been easily prevented or
treated become serious or life-threatening. For example,
women are more likely to examine themselves for signs
of breast cancer than men are to examine their testicles
for unusual lumps.
Sex Differences in Life Expectancy
PHYSICAL AND SOCIAL CHANGES
Although the longevity gap between men and women
is narrowing, life expectancy among men trails that
among women by about 5 years (75.2 years for men
versus 80.4 years for women) (Bloom, 2006).
After we reach our physical peak in our twenties, our
biological functions begin a gradual decline. Aging also
involves adapting to changing physical and social realities. “Young Turks” in the workplace become the “old
FIGURE 17.1
Life Expectancy in Various Counties of the United States
From 1983 to 1999, life expectancy declined significantly in 11 counties for men, and 180 counties for
women. Counties with significant declines were consistent with regional trends in smoking, high blood
pressure, and obesity.
Men
Change in life expectancy
relative to the national average
Significant
decline
No
change
Significant
increase
Women
Source: Ezzati M., Friedman, A. B., Kulkarni, S. C., & Murray, C. J. L. (2008, April 22). The Reversal of Fortunes: Trends in County Mortality and Cross-County Mortality Disparities in the United States. PLoS
Medicine, 5(4), e66.
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In Chapter 15 we reviewed a number of physical
changes that occur as people advance from early adulthood to middle adulthood and, in a number of cases,
to late adulthood (changes in the skin, hair, and nails;
senses; reaction time; lung capacity; metabolism; muscle
strength; bone density; aerobic capacity; blood-sugar tolerance; and ability to regulate body temperature). Here
we revisit and highlight changes in sensory functioning
and bone density as they apply to late adulthood.
© Emma Wood/Alamy
After we reach our physical peak in our twenties, our
biological functions begin a gradual decline.
guard.” One-time newlyweds come to celpeople because of their age.
ebrate their silver and
cataract a condition characgolden anniversaries.
terized by clouding of the lens
Yet aging can involve
of the eye.
more than adjustment;
glaucoma a condition init can bring about pervolving abnormally high fluid
pressure in the eye.
sonal growth and excitpresbycusis loss of acuteing changes in direction
ness of hearing due to ageas well. Even advanced
related degenerative changes
age can bring greater
in the ear.
harmony and integraosteoporosis a disorder
tion to our personin which bones become more
porous, brittle, and subject to
alities. However, we
fracture, due to loss of calcium
must learn to adapt to
and other minerals.
changes in our mental skills and abilities.
Though older people’s memories and fluid intelligence
may not be as keen as they once were, maturity and
experience frequently make them founts of wisdom.
Aging also has social aspects. Our self-concepts
and behavior as “young,” “middle-aged,” or “old”
stem in large measure from cultural beliefs. In Colonial times, “mature” people had great prestige, and men
routinely claimed to be older than they were. Women,
among whom reproductive capacity was valued, did
not do so. By contrast, the modern era has been marked
by ageism —prejudice against people because of their
age. Stereotypes that paint older people as crotchety,
sluggish, forgetful, and fixed in their ways shape the
way people respond to older people and actually impair
their performance (Horton, 2008).
ageism prejudice against
T F
312
In Colonial America, aging was viewed so
positively that men often claimed to be older
than they actually were.
This is true. Maturity was considered a
mark of prestige.
Beginning in middle age, the lenses of the eyes become
brittle, leading to presbyopia, as discussed in Chapter
15. Chemical changes of aging can lead to vision disorders such as cataracts and glaucoma. Cataracts cloud
the lenses of the eyes, reducing vision. Today, outpatient
surgery for correcting cataracts is routine. If performed
before the condition progresses too far, the outcome for
regained sight is excellent. Glaucoma is a buildup of fluid
pressure inside the eyeball. Glaucoma can lead to tunnel
vision (lack of peripheral vision) or blindness. Glaucoma
rarely occurs before age 40, and affects about 1 in 250
people over the age of 40, and 1 in 25 people over 80.
Rates are higher among African Americans than European Americans, and among diabetics than nondiabetics.
Glaucoma is treated with medication or surgery.
The sense of hearing, especially the ability to hear
higher frequencies, also declines with age. Presbycusis is
age-related hearing loss that affects about 1 person in 3
over the age of 65 (Sommers, 2008). Hearing
ability tends to decline more quickly in men
than in women. Hearing aids magnify
sound and can compensate for hearing
loss. The Ten Ways to Recognize Hearing
Loss questionnaire from the NIDCD
provides ways of recognizing hearing loss.
Taste and smell become less
acute as we age. Our sense of smell
decreases almost ninefold from youth to
advanced late adulthood. We also lose
taste buds in the tongue with aging. As
a result, foods must be more strongly
spiced to yield the same flavor.
© BlendImages/Jupiterimages
Changes in Sensory Functioning
Bone Density
Bones begin to lose density in middle
adulthood, becoming more brittle and
vulnerable to fracture. Bones in the spine,
hip, thigh, and forearm lose the most density as we age. Osteoporosis is a disorder in
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sleep apnea temporary
suspension of breathing while
asleep.
Ten Ways to Recognize
Hearing Loss
The following questions from the NIDCD* will help you determine if you need to have your hearing evaluated by a medical
professional:
1. Do you have a problem hearing over the telephone?
2. Do you have trouble following the conversation when two or
more people are talking at the same time?
3. Do people complain that you turn the TV volume up too
high?
4. Do you have to strain to understand conversation?
5. Do you have trouble hearing in a noisy background?
6. Do you find yourself asking people to repeat themselves?
7. Do many people you talk to seem to mumble (or not speak
clearly)?
8. Do you misunderstand what others are saying and respond
inappropriately?
9. Do you have trouble understanding the speech of women
and children?
10. Do people get annoyed because you misunderstand
what they say?
Osteoporosis can shorten one’s
stature by inches and deform one’s
posture, causing the curvature in
the spine known as “dowager’s
hump.” Both men and women are
at risk of osteoporosis, but it poses
a greater threat to women. Men
typically have a larger bone mass,
which provides them with more
protection against the disorder.
Following the decline in bone density that women experience after
menopause, women stand about
twice the risk of hip fractures and
about eight times the risk of spine
fractures that men do. But older
women who engage in walking as
a form of regular exercise are less
likely than their sedentary counterparts to suffer hip fractures (USDHHS, 2005).
SLEEP
Older people need about 7 hours
of sleep per night, yet sleep disorders such as insomnia and sleep
apnea become more common in
later adulthood (Wickwire et al.,
*NIDCD (National Institute on Deafness and Other Communication Disorders). (2008, April 16). Ten Ways to Recognize Hearing Loss. http://www.nidcd.nih.gov/health/hearing/10ways.asp
2008). Sleep apnea sufferers stop
breathing repeatedly during the
night, causing awakenings. Apnea
may be more than a sleep problem.
For reasons that are not entirely
clear, it is linked to increased risk
which bones lose so much calcium that they become
of heart attacks and strokes.
dangerously prone to breakage. An estimated 10 milSleep problems in late adulthood may involve
lion people in the United States over the age of 50 have
physical changes that bring discomfort. Sometimes they
osteoporosis of the hip (USDHHS, 2005). Osteoporosymptomize psychological disorders such as depressis results in more than 1 million bone fractures a year
sion, anxiety, or dementia. Men with enlarged prostate
in the United States, the most serious of which are hip
glands commonly need to urinate during the night,
fractures, that is, breaks in the thigh bone, just below
causing awakening. Other contributing factors include
the hip joint. Hip fractures often result in hospitalizaloneliness, especially after the death of a close friend,
tion, loss of mobility, and, as is often the case, in people
spouse, or life partner.
in advanced late adulthood, death from complications.
Sleep medications are the most common treatment
Fifteen to 20% of the people who sustain a hip fracture
for insomnia (Wickwire et al., 2008). Alternatives may
die within a year (Brunner et al., 2003).
include keeping a regular sleep schedule, challenging
© Radius Images/Jupiterimages
If you answered “yes” to three or more of these questions,
you may want to see an ear, nose, and throat specialist or
an audiologist for a hearing evaluation.
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Preventing Osteoporosis:
Key Messages from the
U.S. Surgeon General
T
here is much that individuals can do to promote their own bone health,
beginning in childhood and continuing into late adulthood. These
activities also contribute to overall health and vitality.
• Eat a well-balanced diet.
• Get the recommended daily requirements for calcium. Three 8-ounce glasses
of low-fat milk each day, combined with the calcium from the rest of a normal
diet, is enough for most individuals.
• If one cannot get enough vitamin D from sunshine, changes in diet and vitamin
supplements can help make up the difference.
• In addition to meeting recommended guidelines for physical activity (at least
30 minutes a day for adults and 60 minutes for children), specific strength- and
weight-bearing activities help build and maintain bone mass throughout life.
Source: Adapted from Bone Health and Osteoporosis: A Report of the Surgeon General, 2005.
exaggerated worries about the consequences of remaining awake, using relaxation techniques, and exercise.
Sleep apnea may be treated with surgery to widen the
upper airways that block breathing or by the use of
devices such as a nose mask that maintains pressure to
keep airway passages open while sleeping (Wickwire et
al., 2008).
(Barnett & Dunning, 2003).
Older people with partners
usually remain sexually active
(Laumann et al., 2006). Most
older people report that they
like sex. Sexual activity among
older people, as among other
groups, is influenced not only
by physical structures and
changes, but also by psychological well-being, feelings of intimacy, and cultural
expectations (Laumann et al.,
2006).
Although many older
people retain the capacity
to respond sexually, physical
changes do occur. But if older
people fine-tune their expectations, they may find themselves leading some of their
most sexually fulfilling years
(Trudel et al., 2007).
Changes in Women
Many of the physical changes in older women stem
from a decline in estrogen production. The vaginal walls
lose much of their elasticity and grow paler and thinner. Thus, sexual activity may become irritating. The
thinning of the walls may also place greater pressure
against the bladder and urethra during sex, sometimes
leading to urinary urgency and a burning sensation during urination.
The vagina also shrinks. The labia majora lose much
Even in the aftermath of the sexual revolution of the
of their fatty deposits and become thinner. The vaginal
1960s, many people still tie sex to reproduction. Thereopening constricts, and penile entry may become diffore, they assume that sex is appropriate only for the
ficult. Following menopause, women also produce less
young. There are unfounded cultural myths to the
vaginal lubrication, and lubrication may take minutes,
effect that older people are sexless and that older men
not seconds, to appear. Lack of adequate lubrication is a
with sexual interests are “dirty old men.” If
key reason for painful sex. Women’s nipples still
older people believe these myths, they may
become erect as they are sexually aroused, but
renounce sex or feel guilty if they remain
the spasms of orgasm become less powersexually active. Older women are
Even in the aftermath ful and fewer in number. Thus, orgasms
handicapped by a double standard of
may feel less intense, even though the
of the sexual
greater tolerance of continued sexuexperience of orgasm may remain just
ality among men.
as satisfying. Despite these changes,
revolution of the 1960s,
However, people do not lose their
women can retain their ability to reach
many
people
still
tie
sexuality as they age (Laumann et al.,
orgasm well into their advanced years.
sex to reproduction.
2006). Sexual daydreaming, sex drive,
Nevertheless, the uterine contractions
and sexual activity all tend to decline with
that occur during orgasm may become disage, but sexual satisfaction may remain high
couragingly painful for some older women.
SEXUALITY
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T F
Women lose the ability to reach orgasm after
the age of 70.
This is not true.
Changes in Men
Age-related changes tend to occur more gradually in
men than in women and are not clearly connected with
any one biological event (Barnett & Dunning, 2003).
Male adolescents may achieve erection in seconds. After
about age 50, men take progressively longer to achieve
erection. Erections become less firm, perhaps because of
lowered testosterone levels (Laumann et al., 2006).
Testosterone production usually declines gradually
from about age 40 to age 60, and then begins to level
off. However, the decline is not inevitable and may be
related to a man’s general health. Sperm production
tends to decline, but viable sperm may be produced by
men in their seventies, eighties, and nineties.
Nocturnal erections diminish in intensity, duration,
and frequency as men age, but they do not normally
disappear altogether (Perry et al., 2001). An adolescent
may require but a few minutes to regain erection and
ejaculate again after a first orgasm, whereas a man in
his 30s may require half an hour. Past age 50, regaining
erection may require several hours.
Older men produce less ejaculate, and the contractions of orgasm become weaker and fewer. Still, an
older male may enjoy orgasm as thoroughly as he did
at a younger age. Following orgasm, erection subsides
more rapidly than in a younger man.
Theories of Aging
s
o far, everyone who has lived has aged—
which may not be a bad fate, considering
the alternative. Although we can make
lengthy lists of the things that happen
as we age, we don’t know exactly why
they happen. Theories of aging fall into two broad
categories:
•
Programmed theories see aging as the result of genetic instructions.
•
Cellular damage theories propose that aging results
from damage to cells.
PROGRAMMED THEORIES OF AGING
Programmed theories propose that aging and longevity
are determined by a biological clock that ticks at a rate
governed by genes. That is, the seeds of our own demise
are carried in our genes. Evidence supporting a genetic
link to aging comes in part from studies showing that
longevity tends to run in families (Perls, 2005). For
example, the siblings of centenarians are more likely
than members of the general population to live to be
100 themselves (Perls et al., 2002).
But why should organisms carry “suicidal” genes?
Programmed aging theorists believe that it would be
adaptive for species to survive long enough to reproduce
© Yoshida-Fujifotos/The Image Works
Patterns of Sexual Activity
Despite decline in physical functions, older people can
lead fulfilling sex lives. Years of sexual experience may
more than compensate for any lessening of physical
response (Laumann et al., 2006). Frequency of sexual
activity tends to decline with age because of hormonal
changes, physical problems, boredom, and cultural
attitudes. Yet sexuality among older people is variable
(Laumann et al., 2006). Many older people engage in
sexual activity as often as or more often than when
younger; some develop an aversion to sex; others lose
interest.
Couples may adapt to the physical changes of aging
by broadening their sexual repertoire to include more
diverse forms of stimulation. The availability of a sexually interested and supportive partner may be the most
important determinant of continued sexual activity
(Laumann et al., 2006).
Twins Gin Kanie (left) and Kin Narita lived to the
ages of 108 and 107.
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theory of aging focusing on
the limits of cell division.
telomeres protective segments of DNA located at the
tips of chromosomes.
hormonal stress theory
a theory of aging that hypothesizes that stress hormones,
left at elevated levels, make
the body more vulnerable to
chronic conditions.
immunological theory
a theory of aging that holds
that the immune system is
preset to decline by an internal biological clock.
and transmit their genes
to future generations.
From the evolutionary perspective, there
would be no advantage to the species (and
probably a disadvantage given limited food
supplies) to repair cell
machinery and body
tissues to maintain life
indefinitely.
Cellular clock theory focuses on the built-
in limits of cell division.
After dividing about
wear-and-tear theory a
fifty times, human cells
theory of aging that suggests
that over time our bodies becease dividing and evencome less capable of repairing
tually die (Hayflick,
themselves.
1996).
Researchers
free-radical theory a
find clues to the limits
theory of aging that attributes
of cell division in teloaging to damage caused by
the accumulation of unstable
meres, the protective
molecules called free radicals.
segments of DNA at the
cross-linking theory a
tips of chromosomes.
theory of aging that holds that
Telomeres shrink each
the stiffening of body proteins
time cells divide. When
eventually breaks down bodily
processes, leading to aging.
the loss of telomeres
reaches a critical point
after a number of cell
divisions, the cell may no longer be able to function
(Epel et al., 2006). The length of the telomeres for a
species may determine the number of times a cell can
divide and survive.
Hormonal stress theory focuses on the endocrine
system, which releases hormones into the bloodstream.
Hormonal changes foster age-related changes such as
puberty and menopause. As we age, stress hormones,
including corticosteroids and adrenaline, are left at elevated levels following illnesses, making the body more
vulnerable to chronic conditions such as diabetes, osteoporosis, and heart disease. The changes in production
of stress hormones over time may be preprogrammed
by genes.
Immunological theory holds that the immune system is preset to decline by an internal biological clock.
For example, the production of antibodies declines
with age, rendering the body less able to fight off infections. Age-related changes in the immune system also
increase the risk of cancer and may contribute to general deterioration.
316
Free radicals may also be produced by exposure to environmental agents such as ultraviolet light, extreme heat,
pesticides, and air pollution.
CELLULAR DAMAGE THEORIES
OF AGING
Programmed theories assume that internal bodily processes are preset to age by genes. Cellular damage theories propose that internal bodily changes and external
environmental assaults (such as carcinogens and toxins)
cause cells and organ systems to malfunction, leading
to death. For example, the wear-and-tear theory suggests that over the years, our bodies—as machines that
wear out through use—become less capable of repairing themselves.
The free-radical theory attributes aging to damage caused by the accumulation of unstable molecules
called free radicals. Free radicals are produced during metabolism by oxidation, possibly damaging cell
proteins, membranes, and DNA (Sierra, 2006). Most
free radicals are naturally disarmed by nutrients and
enzymes called antioxidants. Most antioxidants are
either made by the body or found in food. As we age,
our bodies produce fewer antioxidants (Rattan et al.,
2006). People whose diets are rich in antioxidants are
less likely to develop heart disease and some cancers.
As we age, cell proteins bind to one another in a
process called cross-linking, thereby toughening tissues.
Cross-linking stiffens collagen—the connective tissue
supporting tendons, ligaments, cartilage, and bone. One
result is coarse, dry skin. (Flavored animal collagen is
called gelatin, better known by the brand name Jell-O.)
Cross-linking theory holds that the stiffening of body
proteins accelerates and eventually breaks down bodily
processes, leading to some of the effects of aging (Rattan et al., 2006). The immune system combats crosslinking, but becomes less able to do so as we age.
In considering the many theories of aging, we
should note that aging is an extremely complex biological process that may not be explained by any single
theory or cause. Aging may involve a combination of
these and other factors.
© liquidlibrary/Jupiterimages
cellular clock theory a
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Is Calorie Restriction the Fountain of Youth?
R
Health Concerns
and Aging
t
hough aging takes a toll on our bodies, many
gerontologists believe that disease is not inevitable. They distinguish between normal aging
and pathological aging. In normal aging,
physiological processes decline slowly with
age and the person is able to enjoy many years of health
and vitality into late adulthood. In pathological aging,
chronic diseases or degenerative processes, such as heart
disease, diabetes, and cancer, lead to disability or premature
death. Older persons typically need more health care than
younger persons. Though people over the age of 65 make
up about 12% of the population, they occupy 25% of the
hospital beds. As the numbers of older people increase in
the 21st century, so will the cost of health care.
Medicare, a federally controlled health insurance program for older Americans and the disabled, only partially
subsidizes the health care needs of these groups. Another government program, Medicaid, covers a portion of the health
care costs of people of all ages who are otherwise unable to
afford coverage. Many older adults use both programs.
It is not true that most older adults require institutional care, such as nursing homes or residential care
© Image Source Black/Jupiterimages
estricting calories by approximately 30% may trigger anti-aging responses
that evolved to increase the chances of survival when food is scarce.
For example, calorie restriction in humans, non-human primates, and
other mammals lowers blood pressure, cholesterol, and blood sugar
and insulin levels. It strengthens the immune system and lowers the fat mass
(Roth et al., 2004). Calorie restriction also fends off Alzheimer-like symptoms in
rhesus monkeys.
In laboratory experiments, mice were fed a diet that was 30% to 40% lower in
calories than normal but contained all necessary nutrients. The development of chronic
diseases and cancers was retarded, and the mice lived 50% beyond their normal life spans (Hursting et al., 2003).
Raising levels of the hormone DHEAS (dehydroepiandrosterone sulfate) may be one way that calorie restriction reduces the risk of cancer and improves immune system functioning. DHEAS production usually begins to
decline after approximately age 30, dipping to as low as 5% to 15% of peak levels by age 60. DHEAS levels are
higher than normal in long-lived men and in rhesus monkeys with calorie-restricted diets (Chong et al., 2004).
It remains to be seen whether, and by how much, calorie restriction extends the life span of people who
have access to modern health care. Moreover, it is difficult enough for many people to keep their weight within
normal limits. How willing would we be to lower our calorie intake further? Researchers are therefore also seeking alternate ways of triggering the anti-aging responses caused by calorie restriction.
facilities. More than two of three adults age 65 and
older live in their own homes. Less than 10% of older
adults live in nursing homes or other long-term care
facilities. The population of nursing homes is made up
largely of people age 80 and older. Yet if older adults
live long enough, nearly half will eventually require
some form of nursing or home health care.
T F
Most older adults require institutional care.
This statement is false. More than 2/3 of
adults over the age of 65 live in their own
homes.
It is also untrue that most older Americans spend
their later years in a retirement community. The majority of older adults remain in their own communities
after retirement. Moreover, despite beliefs that most
older people are impoverished, Americans aged 65 and
above are actually less likely than the general population to live under the poverty level.
In 1900, older people were more likely to die from
infectious diseases such as influenza and pneumonia than
they are today. Today, older people are at greater risk of
dying from chronic diseases such as heart disease and
cancer. More than four out of five people over the age
of 65 have at least one chronic health problem (Heron,
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317
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FIGURE 17.2
ong
m
a
s
n
io
it
d
n
o
C
h
lt
Chronic Hea nd Over
People Age 65 a
people in late
of 40 and 79, and men between the ages of 60 and
79, but heart disease is the nation’s leading cause of
death among both sexes beyond the age of 80.
The risk of most cancers rises as we age
because the immune system becomes less able to
rid the body of precancerous and cancerous cells.
Many older people are not adequately screened
or treated for cancer or heart disease. One reason for the gap in diagnosis and treatment is
elder bias (Ludwick & Silva, 2003), or discrimination against the elderly on the part of some
health professionals.
Among the top chronic conditions listed in
Figure 17.2, several are also leading causes of
death or pose significant risk factors for mortality. Hypertension, which affects about 50%
of Americans over the age of 65, is a major risk
factor for heart attacks and strokes. Diabetes,
the fifth most common chronic illness, is the
sixth leading cause of death. Other chronic
conditions, such as cataracts, chronic sinusitis, visual impairment, and varicose veins,
are rarely fatal but can lead to disability.
ns affecting
health conditio
c
ni
ro
ch
g
in
ad
and arthritis.
The le
, heart disease,
on
si
en
rt
pe
hy
adulthood are
d
Who Reporte
65 and Over
ge
A
le
x
op
Se
Pe
onditions, by
Percentage of
ed Chronic C
Having Select
60
Men
Women
50
40
30
20
s
pt
om
es
et
er
m
ab
ARTHRITIS
Arthritis is joint inflammation that results
Ar
ro
th
rit
ic
sy
nc
y
ca
ch
An
Di
itis
a
m
on
th
ni
c
br
As
Ch
ys
em
ke
ro
St
ph
Em
ns
rte
pe
Hy
He
ar
td
ise
as
io
e
n
0
a
10
from conditions affecting the structures
inside and surrounding the joints. SympReports, 50(5)
nal Vital Statistics
sr/
ron. (2007). Natio
He
v/nchs/data/nv
P.
.go
ie
dc
lan
w.c
Me
tion. ww
Source:
ntrol and Preven
Co
e
eas
Dis
for
Centers
5
nvsr56/nvsr56_0
TABLE 17.2
Ten Leading Cause
Both Sexes,65Year s of Death,All Races,
s and Over*
2007). Some, like
arthritis inflammation of
varicose
veins,
the joints.
are minor. OthCAUSE OF DEATH
ers, like heart disease, pose serious health risks. Figure 17.2 shows
Heart disease
the percentages of people age 65 and older who
Cancer
are affected by common chronic health conditions. While longevity is increasing, so too are
Stroke
the number of years older persons are living
Chronic respirat
with one or more chronic health problems.
ory diseas
HEART DISEASE, CANCER,
AND STROKE
The three major causes of death of Americans
age 65 and older are heart disease, cancer, and
stroke (see Table 17.2). Cancer is the leading
cause of death in women between the ages
es
Alzheimer’s dise
ase
ANNUAL NUMBER OF
DEATHS PER 100,000
1,469
PEOPLE
1,063
360
290
180
Diabetes
Influenza and pn
149
Kidney diseases
145
Accidents
Blood poisonin
eumonia
97
g
97
71
318
PART 5 : MIDDLE AND LAT E ADULT HOOD
HDEV_17_Ch17_308-327.indd 318
*Source: Melan
ie P. Heron. (20
07). National Vit
www.cdc.gov/n
al Statistics Rep
chs/data/nvsr/
orts, 56(5). Cente
nvsr56/nvsr56_0
rs for Disease Co
5.pdf
ntrol
and Prevention.
11/14/08 9:21:32 AM
toms progress from redness to heat, swelling, pain, and
loss of function. Children can also be affected by arthritis, but it is more common with advancing age. Arthritis is more common in women than men and in African
Americans than European Americans. Osteoarthritis and
rheumatoid arthritis are the two most common forms of
arthritis.
Osteoarthritis is a painful, degenerative disease characterized by wear and tear on joints. By the age of 60,
more than half of Americans show some signs of the disease. Among people over the age of 65, two of three have
the disease. The joints most commonly affected are in the
knees, hips, fingers, neck, and lower back. Osteoarthritis
is caused by erosion of cartilage, the pads of fibrous tissue
that cushion the ends of bones. As cartilage wears down,
bones grind together, causing pain (Axford et al., 2008).
Osteoarthritis is more common among obese people
because excess weight adds to the load on the hip and
knee joints. Health professionals use over-the-counter
anti-inflammatory drugs (aspirin, acetaminophen, ibuprofen, naproxen) and prescription anti-inflammatory drugs
to help relieve pain and discomfort (Axford et al., 2008).
In severe cases, joint replacement surgery may be needed.
Specific exercises are also sometimes prescribed.
Rheumatoid arthritis is characterized by chronic
inflammation of the membranes that line the joints
because the body’s immune system attacks its own tissues. The condition affects the entire body. It can produce
unrelenting pain and eventually lead to severe disability.
Bones and cartilage may also be affected. Onset of the
disease usually occurs between the ages of 40 and 60.
Anti-inflammatory drugs are used to treat it.
© Sean Murphy/Getty Images
SUBSTANCE ABUSE
2005; Pawaskar & Sansgiry, 2006):
osteoarthritis a painful,
degenerative disease characterized by wear and tear on joints.
1.
The dosage of
drugs is too high.
rheumatoid arthritis a
painful, degenerative disease
Because bodily
characterized by chronic infunctions slow with
flammation of the membranes
age (such as the
that line the joints.
ability of the liver
and kidneys to clear
drugs out of the body), the same amount of drug can
have stronger effects and last longer in older people.
2.
Some people may misunderstand directions or be unable to keep track of their usage.
3.
Many older persons have more than one doctor, and
treatment plans may not be coordinated.
T F
Substance abuse is rare in late adulthood.
This is not true.
Although alcohol consumption is lower overall
among older people as compared to younger adults,
many older adults suffer from long-term alcoholism.
However, the health risks of alcohol abuse increase
with age. The slowdown in the metabolic rate reduces
the body’s ability to metabolize alcohol, increasing the
likelihood of intoxication. The combination of alcohol
and other drugs, including prescription drugs, can be
dangerous or even lethal. Alcohol can also lessen or
intensify the effects of prescription drugs.
ACCIDENTS
Though accidents can occur at any age, older people
face greater risks of unintentional injuries from falls,
motor vehicle accidents, residential fires, and nonfatal
Abuse of medication (prescription and over-the-counter
drugs), much of which is unintentional, poses a serious
health threat to older Americans. Forty percent of all prescription drugs in the United States are taken by people
age 60 and older, and more than half of them take two
to five medications daily (Johnson-Greene & Inscore,
2005). Among the most commonly used drugs are blood
pressure medication, tranquilizers, sleeping pills, and
antidepressants. Taken correctly, prescription drugs can
be of help. If used incorrectly, they can be harmful.
It is not true that substance abuse is rare in late adulthood. Millions of older adults are addicted to, or risk
becoming addicted to, prescription drugs, especially tranquilizers. About a quarter of a million older adults are
hospitalized each year because of adverse drug reactions.
Reasons include the following (Johnson-Greene & Inscore,
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poisoning. Accidents
are the ninth leading
characterized by deterioration
cause of death among
of cognitive functioning.
older Americans. Falls
Alzheimer’s disease
are especially dangerous
(AD) a severe form of
dementia characterized by
for older adults with
memory lapses, confusion,
osteoporosis because
emotional instability, and
of the increased risks of
progressive loss of cognitive
fractures (Facts about
functioning.
Falling, 2008).
Many
accidents
involving older adults could be prevented by equipping
the home with safety features such as railings and nonskid
floors. Wearing proper glasses and using hearing aids can
reduce the risk of accidents resulting from vision or hearing problems, including many motor vehicle accidents.
Adherence to safe driving speeds is especially important
among older drivers because they have slower reaction
times than do younger drivers.
tions such as meningitis, HIV infection, and encephalitis;
and chronic alcoholism, infections, strokes, and tumors
(Lippa, 2008; see Figure 17.3). The most common cause
of dementia is Alzheimer’s disease (AD), a progressive
brain disease affecting 4–5 million Americans.
The risk of AD increases dramatically with age
(Figure 17.4). About 1 in 10 Americans over the age of
65 has AD, jumping to more than 1 in 2 among those
in the 75 to 84 years old. AD is rare in people under the
age of 65 (Lippa, 2008). Although some dementias may
be reversible, especially those caused by tumors and
treatable infections and those that result from depression or substance abuse, the dementia resulting from
AD is progressive and irreversible (Lippa, 2008).
AD is the fifth leading killer of older Americans. It
progresses in several stages. At first there are subtle cognitive and personality changes in which people with AD
have trouble managing finances and recalling recent
events. As AD progresses, people find it harder to manage
daily tasks, select clothes, recall names and addresses, and
drive. Later, they have trouble using the bathroom and
maintaining hygiene. They no longer recognize family and
friends or speak in full sentences. They may become restless, agitated, confused, and aggressive. They may get lost
Dementia is a condition characterized by dramatic detein stores, parking lots, even their own homes. They may
rioration of mental abilities involving thinking, memory,
experience hallucinations or paranoid delusions, believing
judgment, and reasoning. Dementia is not a consequence
that others are attempting to harm them. People with AD
of normal aging, but of disease processes that damage
may eventually become unable to walk or communicate
brain tissue. Some causes of dementia include brain infecand become completely dependent on others.
Although the cause or causes of AD remain a
mystery, scientists believe that both environmental
and genetic factors are involved (Goldman et al.,
FIGURE 17.3
2008; Tomiyama et al., 2008). It is possible that
the accumulation of plaque causes the memory loss
and other symptoms of AD; however, experiments
use of dementia.
ca
g
in
ad
le
e
th
with non-humans suggest that memory deficits
ase is
Alzheimer’s dise
%
.5
14
,
ke
may precede the formation of significant deposits
Stro
es, 12.2%
Multiple caus
of plaque (Jacobsen et al., 2006).
Medicines can help improve memory functions
Parkinson’s
in people with AD, but their effects are modest.
disease, 7.7%
Researchers are investigating whether regular use
of anti-inflammatory drugs and antioxidants may
0%
Brain injury, 4.
lower the risk of developing AD by preventing the
0%
brain inflammation associated with AD (Gray et al.,
4.
,
Other causes
2008; Meinert & Breitner, 2008). Calorie restriction
may prevent the accumulation of plaque (Qin et al.,
2006). Researchers are also investigating whether
cognitive training that focuses on the enhancement
Alzheimer’s
%
of memory and processing speed can delay or predisease, 57.6
vent the development of AD (Acevedo & Loewenstein, 2007; Vellas et al., 2008).
ol and Prevendementia a condition
DEMENTIA AND ALZHEIMER’S
DISEASE
Causes of Dementia
s, 56(5).
Statistics Report
). National Vital
P. Heron. (2007
vsr56_05
6/n
Source: Melanie
sr5
nv
sr/
v/nchs/data/nv
tion. www.cdc.go
320
ease Contr
Centers for Dis
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11/14/08 9:21:45 AM
FIGURE 17.4
Rates of Alzheimer
among Older Adult’s Disease
s
The risk of Alzhe
imer’s disease is
greatest among
75- to 84-year ag
people in the
e range.
60
50
Prevalence (%
)
40
30
20
But Tworkov seemed more at ease in his attire
at 79 than I had been at 16.
Tworkov was fortunate in that his cognitive processes were clear. Given the scores of
new works he showed us, it also appeared that
his processing speed had remained good—or
at least good enough. His visual and motor
memory and his capacity to rivet his attention
to a task all remained superb. All these skills
are part of what we labeled fluid intelligence
in Chapter 15, and they are most vulnerable
to decline in late adulthood (Saggino et al.,
2006). We had no personal way of comparing
these skills to what they were 20 or 40 years earlier, but based simply on what we saw, we were
stunned at his ability.
Crystallized intelligence can continue to improve
throughout much of late adulthood (Mangina &
Sokolov, 2006). However, if you have another look at
Figure 15.3 on page 289, you will see that all cognitive
skills, on average, tend to decline in advanced age.
10
MEMORY: REMEMBRANCE OF
THINGS PAST—AND FUTURE
0
65 –74
75 – 84
Age Range
Source: Herbert,
L. E., et al. (2003
). Alzheimer’s Dis
2000 Census. Arc
ease in the U.S
hives of Neurolog
. Population: Pre
y, 60, 1119–112
valence Estimate
2.
s Us
ing the
Cognitive
Development
m
y wife studied the work of artist Jack Tworkov. When he was
in his 30s, his paintings were
realistic. In his 50s, his works
were abstract expressionistic,
like those of Jackson Pollock. In his 60s, his painting
remained abstract and became hard-edged with geometric precision. At the age of 79, a year before his
death, he was experimenting with a loosely flowing calligraphic style that he never showed to the public. It
was in the early stages of development.
Although Tworkov’s body was in decline, he told
my wife, “Every morning I go to the easel in a fever.” He
wore a T-shirt and blue jeans, and something about him
reminded me of the self I had projected as a teenager.
In a classic study of memory, Harry Bahrick and his
colleagues (1975) sought to find out how well high
school graduates would recognize photographs of
their classmates. Some of their subjects had graduated 15 years earlier, and others had been out of
school for some 50 years. The experimenters interspersed photos of actual classmates with four times as
many photos of strangers. People who had graduated
15 years earlier correctly recognized persons who were
former schoolmates 90% of the time. But those who
had graduated about 50 years earlier still recognized
former classmates 75% of the time. A chance level of
recognition would have been only 20% (one photo in
five was of an actual classmate). Thus, the visual recognition memories had lasted half a century in people
who were now in late adulthood.
Developmentalists speak of various kinds of
memories. First we can distinguish between retrospective and prospective memories—memories of the past
(“retro”) and memories of the things we plan to do in
the future. We can then divide retrospective memories
into explicit and implicit memories. Explicit memories
are of specific information, such as things we did or
things that happened to us (called episodic or autobiographical memories) and general knowledge, such
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as the author of
Hamlet (semantic
memory). Implicit
memories
are
more automatic and
recall the performance
of tasks such as reciting
the alphabet or multiplication
tables, riding a bicycle, or using
a doorknob.
Explicit versus Implicit
Memories
Older adults often
complain that they
implicit memory autostruggle to remember
matic memories based on
the names of people
repetition and apparently not
they know, even people
requiring any conscious effort
to retrieve.
they know very well.
They are frustrated by
the awareness that they
knew the name yesterday, perhaps even a half hour
ago, but “now” it is gone. When they do recall it, or
another person reminds them of the name, they think,
“Of course!” and perhaps belittle themselves for forgetting. An experiment with young adults and adults in
their 70s found that the older adults did have a disproportionate difficulty naming pictures of public figures,
but not of uncommon objects (Rendell et al., 2005).
It seems that the working memories of older adults
hold less information simultaneously than the working
memories of young adults. Perhaps, then, when they are
picturing the person whose name they forget, or thinking about that person engaged in some activity, the picture or activity momentarily displaces the name (Braver
& West, 2008).
The temporal memory of older adults—that is, their
recall of the order in which events have occurred—may
become confused (Dumas & Hartman, 2003; Hartman
& Warren, 2005). Older adults may have difficulty discriminating actual events from illusory events (Rybash
& Hrubi-Bopp, 2000).
Older adults usually do not fare as well as younger
adults in tasks that measure explicit memory, but they
tend to do as well, or nearly as well, in tasks that assess
implicit memory (Mitchell & Bruss, 2003). Implicit
memory tasks tend to be automatic and do not require
any conscious effort. They may reflect years of learn-
322
It is said that you never forget
how to ride a bicycle or to use a
keyboard: these are also implicit
memories—in these cases,
sensorimotor habits.
ing and repetition. Examples include one’s memory of
multiplication tables or the alphabet. I could ask you
which letter comes after p or to recite the alphabet. The
second task would be easier because that is the way in
which you learned, and overlearned, the 26 letters of
the alphabet. It is said that you never forget how to ride
a bicycle or to use a keyboard; these are also implicit
memories—in these cases, sensorimotor habits.
Daniel Schacter (1992) illustrates implicit memory with the story of a woman with amnesia who was
found wandering the streets. The police picked her up
and found that she could not remember who she was or
anything else about her life, and she had no identification. After extensive fruitless questioning, the police hit
on the idea of asking her to dial phone numbers—any
number at all. Although the woman did not “know”
what she was doing, she dialed her mother’s number. She
could not make her mother’s number explicit, but dialing it was a habit, and she remembered it implicitly.
© AP Photo/Holmberg
“Who is the author of the play Hamlet?
That is the question.”
Associative Memory
We use associative learning, and associative memory, to
remember that the written letter A has the sound of an
“A.” We also use associative memory to develop a sight
vocabulary; that is, we associate the written the with
the sound of the word; we do not decode it as we read.
In these cases we usually learn by rote rehearsal, or
repletion. But we also often use elaborative rehearsal,
which is a more complex strategy that makes learning
meaningful, to retrieve the associated spellings for spoken words. For example, we may remember to recall
the rule “i before e except after c” to retrieve the correct
spelling of retrieve.
It turns out that aging has more of a detrimental effect on associative memory than on memory for
single items (Naveh-Benjamin et al., 2007). For example, older adults have greater difficulty discriminating
between new and already experienced combinations of
items on an associative recognition task—that is, recognizing pairs of words that have been presented before—
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Long-Term Memory
Long-term memory has no known inherent limits, as
noted in Chapter 9. Memories may reside there for a
lifetime, to be recalled with the proper cues. But longterm memories are also subject to distortion, bias, and
even decay.
Harry Bahrick and his colleagues (2008) administered questionnaires to 267 alumni of Ohio Wesleyan University, who had graduated anywhere from 1
to 50 years earlier. Subjects thus ranged in age from
early adulthood to late adulthood. They were asked to
FIGURE 17.5
The Aging Brain
In the aging brai
n, atrophy in th
e frontal lobe an
the middle (med
d in
ial) part of the te
mporal lobe may
account for defi
cits in associativ
e memory.
FRONTAL
LOBE
PARIETAL
LOBE
OCCIPITAL
LOBE
ages/Jupiterim
ages
TEMPORAL
LOBE
© Thinkstock Im
than between new and already experienced single items
on an item recognition task (Light et al., 2004). Various
possibilities have been hypothesized to explain the agerelated deficit in associative memory. One is an impairment in the initial binding or learning phase of individual
pieces of information when the individual in attempting
to encode them (Naveh-Benjamin et al., 2003). According to the binding hypothesis, older adults are impaired
primarily in associating items with one another, but not
in remembering individual items (Cohn et al., 2008). A
second hypothesis states that the specific impairment is
in recollection when the individual attempts to retrieve
the information (Yonelinas, 2002), which may reflect
poor binding during encoding, poor use of strategic
processes during retrieval, or both.
Research by Melanie Cohn and her colleagues
(2008) suggests that impairments in associative memory among older adults represent problems in binding
information, recollection, and use of effective strategies
for retrieval (such as creating sentences which use both
members of a pair of words as they are presented). For
example, if one member of a pair is “man” and another
is “cigarette,” an elaborative strategy for recollecting
the pair could be to rapidly construct the sentence, “The
man refuses to smoke a cigarette.” Cohn and her colleagues believe that these cognitive developments “are
consistent with neurobiological models” of memory
that focus on the frontal and medial temporal lobes
of the brain (Figure 17.5). The frontal regions—the
executive center of the brain—are involved in directing
one’s attention and organizing information and strategic
processes. The medial temporal lobe binds elements to
form memory traces, recovers information in response
to use of proper memory cues, and is therefore a key to
recollection. Neurological research shows that deterioration is evident in aging in the frontal lobes and to a
lesser degree in the medial temporal lobe, thus logically
impairing binding, recollection, and the use of effective
strategies for the retrieval of information.
recall their college grades, and their recollections were
checked against their actual grades. Of 3,967 grades,
3,025 were recalled correctly. Figure 17.6 on the next
page relates correct responses to the age of the respondent. The number of correct recollections fell off with
the age of the respondent, due, generally, to errors
of omission—that is, leaving items blank rather than
entering the wrong grade. As a matter of fact, graduates
who were out of school more than 40 years entered no
more wrong grades, on average, than those who were
out of school 8 years or so. The researchers found a
grade-inflation bias: 81% of commission errors inflated
the true grade.
In typical studies of long-term memory, researchers
present older adults with timelines that list ages from
early childhood to the present day and ask them to fill
in key events and to indicate how old they were at the
time. Using this technique, people seem to recall events
from the second and third decades of life in greatest
detail and with the most emotional intensity (Glück
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FIGURE 17.6
Memory for College Grades,One to Fifty-FourYears Later
Mean number of correctly recalled grades, omission errors, and commission errors as a function of
retention interval.
18
Correct Recalls
Omission Errors
Commision Errors
16
Mean Number of Course Grades
14
12
10
8
6
4
2
0
0
5
10
15
20
25
30
35
40
45
50
Retention Interval in Years
Source: Harry P. Bahrick, Lynda K. Hall, & Laura A. Da Costa. (2008). Fifty years of memory of college grades: Accuracy and distortions. Emotion, 8(1), 13–22.
& Bluck, 2007). These
prospective memory
include early romances
memory of things one has
(or their absence), high
planned for the future.
school days, music
groups and public
figures, sports heroes, “life dreams,” and early disappointments. Many psychologists look to psychological
explanations for these findings, and, considering “coming of age” and the development of “identity” are common characteristics of the second and third decades of
life, they may be correct in their pursuit. But let us note
that sex hormones also have their strongest effects in
adolescence and early adulthood and that the secretion
of these hormones is connected with the release of neurotransmitters that are involved in memory formation
(Lupien et al., 2007).
324
Prospective Memory
Why do we need electronic organizers, desk calendars,
and shopping lists? To help us remember the things we
have planned to do. Retrospective memory helps us
retrieve information from the past. Prospective memory
aids us in remembering things we have planned to do
in the future, despite the passage of time and despite
the occurrence of interfering events. In order for prospective memory to succeed, we need to have foolproof
strategies, such as alarm reminders on our cell phones,
or we need to focus our attention and keep it focused.
Distractibility will prevent us from reaching the goal.
A Swiss study examined the relationships between
processing speed, working memory (the amount of
information a person can keep in mind at once), prospective memory, and retrospective memory among
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361 people between the ages of 65 and 80 (Zeintl et al.,
solving skills. The goal is to attach the candle to the
2007). It was found that age-related declines in processwall, using only the objects shown, so that it will burn
ing speed and working memory—aspects of fluid intelliproperly. Rather than be concerned about whether or
gence—had important effects on retrospective memory.
not you solve the problem, notice the types of thoughts
However, there were age-related declines in prospective
you have already had as you have surveyed the objects
memory that appeared to be independent of processin the figure. Even if you haven’t arrived at a solution
ing speed and working memory. In other words, even if
yet, you have probably used mental trial and error to
fluid intelligence remained intact, prospective memory
visualize what might work. (You will find the answer to
might decline, suggestive of powerful roles for attention
the Duncker Candle Problem on the next page.)
and distractibility.
These standard problem-solving methods require
Another study found that the age-related decline
executive functioning to select strategies, working memin prospective memory is greatest when the task to be
ory to hold the elements of the problem in mind, and
completed is not crucial and the cues used to jog
processing speed to accomplish the task while
the memory are not very prominent (Kliegel
the elements remain in mind, all of which
et al., 2008). When the task is important
have fluid components that tend to
and older adults use conspicuous cues
decline with age (Hassing & JohansBecause of the decline
to remind them, age-related declines
som, 2005). Experiments with young
in working memory and
in prospective memory tend to disand older adults consistently show
because of impairments in
appear. However, the adults have
that the older adults use fewer
to be cognitively intact enough to
strategies and display slower prohearing, many older adults
plan the strategy.
cessing speed in solving complex
find it more difficult to
math problems (Allain et al., 2007;
Lemaire & Arnaud, 2008).
understand the spoken
How important, you might wonlanguage.
der, is it for older people to solve complex math problems or “teasers” like the
People aged 75 and above tend to show a
decline in reading comprehension that is related to
a decrease in the scope of working memory (De Beni et
FIGURE 17.7
al., 2007). Because of the decline in working memory
and because of impairments in hearing, many older
adults find it more difficult to understand the spoken
language (Burke & Shafto, 2008). However, when the
Can you use the
objects shown
on the table to
speaker slows down and articulates more clearly, comthe candle to th
attach
e wall of the room
prehension increases (Gordon-Salant et al., 2007).
so that it will bu
properly? You ca
rn
n find the answ
Older adults may also show deficiencies in language
er on page 326.
production. Although they may retain their receptive
vocabularies, they often show a gradual decline in their
expressive vocabularies—that is, the number of words
they produce (Hough, 2007). It appears that declines
in associative memory and working memory decrease
the likelihood that words will “be there” when older
people try to summon up ideas (Burke & Shafto, 2008).
Similarly, older people are more likely to experience the
frustrating “tip-of-the-tongue” phenomenon, in which
they are certain that they know a word but temporarily
cannot produce it (Shafto et al., 2007).
LANGUAGE
DEVELOPMENT
The Duncker Cand
le Problem
PROBLEM SOLVING
Figure 17.7 shows the so-called Duncker Candle Problem, which is sometimes used to challenge problem-
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© Comstock Images/Jupiterimages
Duncker Candle Problem? The answer depends on what
people are attempting to accomplish in
life. However, research suggests that for the vast
majority of older
adults, abstract
problemsolving ability,
as in complex
math
problems, is not related
to their quality of
life. “Real-world”
or everyday problemsolving skills are usually of greater concern (Gilhooly et al., 2007).
Moreover, when older adults encounter interpersonal conflicts, they tend to regulate their emotional
responses differently from young and middle-aged
adults. Whereas the younger groups are relatively more
likely to express feelings of anger or frustration, to seek
support from other people, or to solve interpersonal
problems, the older adults are more likely to focus on
remaining calm and unperturbed (Coats & BlanchardFields, 2008). The difference appears to be partially due
to older adults’ decreased tendency to express anger
and increased priority on regulating emotion. Perhaps
the older adults do not wish to be “jarred,” but it also
sounds a bit like wisdom.
WISDOM
of
fe
i
L
Kunzmann
and
Baltes
(2005)
note that wise people
approach life’s problems in a way that
addresses the
meaning of
life. They
consider
not only
the present,
but
also the past
and the future,
as well as the
contexts in which the
problems arise. They tend to be tolerant of other people’s value systems and to acknowledge that there are
uncertainties in life and that one can only attempt to
find workable solutions in an imperfect world. Ardelt
(2008a, 2008b) adds emotional and philosophical
dimensions to the definition of wisdom. She suggests
that wise people tend to possess an unselfish love for
others and tend to be less afraid of death.
ng
i
n
ea
M
e
h
T
FIGURE 17.8
Answer to the Duncker
Candle Problem
We may seek athletes who are in their twenties, but we
prefer coaches who are decades older. It may be desirable to hire high school teachers and college professors
who have recently graduated, but we seek high school
principals and department chairpersons who are somewhat older. It is helpful to have 18-year-olds who are
bursting with energy knocking on doors to get out the
vote, but we want our presidential candidates to be
older. Why? Because we associate age with wisdom.
Among the numerous cognitive hazards of aging,
older people tend to be more distractible than young
adults. Developmental psychologist Lynn Hasher
(2008) suggests that distractibility can enable older
adults to take a broader view of various situations: “A
broad attention span may enable older adults to ultimately know more about a situation and . . . what’s
going on than their younger peers. . . . [This] characteristic may play a significant role in why we think of older
people as wiser.”
326
PART 5 : MIDDLE AND LAT E ADULT HOOD
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With HDEV you have a multitude of study aids at your fingertips.
After reading the chapters, check out these ideas for further help.
Chapter in Review cards include all learning outcomes,
definitions, and summaries for each chapter.
Printable flash cards give you three additional
ways to check your comprehension of key
human development concepts.
Other great ways to help you study include interactive
flashcards, downloadable study aids, games, quizzes
with feedback, and PowerVisuals to test your knowledge
of key concepts.
You can find it all at 4ltrpress.cengage.com/hdev.
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