Transcript Life Span
Life Expectancy and Life Span
Life Span: the maximum number of years an
individual can live; has remained between 120–125
years
Life Expectancy: the number of years that the average
person born in a particular year will probably live
Has increased an average of 30 years since 1900
Average life expectancy today is 77.6 years
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Life Expectancy and Life Span
Cross-Cultural Differences:
Japan has highest life expectancy (81 years)
Differences in life expectancy across countries are due to
factors such as health conditions and medical care
Ethnic Differences:
Life expectancy for African Americans is 7 years lower
than that of non-Latino Whites
Females’ ability to outlive males widens beginning
in the mid-thirties
Social factors (health, attitudes, habits, lifestyles,
occupation)
Biological factors
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Life Expectancy and Life Span
Number of centenarians is increasing by approximately 7%
each year
Getting older may not mean getting sicker
Many centenarians are women
Among centenarians, men are more likely to be healthier than women
Ability to cope successfully with stress seems to be important to
survival
Other important factors:
Genes and family history
Health, education, personality, and lifestyle
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Young-Old, Old-Old, Oldest-Old
Some developmentalists divide late adulthood:
Young-old are aged 65 to 74
Old-old are aged 75 or more
Oldest-old are aged 85 or more
Important to consider function rather than age
Differences between levels of “old”:
Compared with oldest-old, young-old have a greater potential
for physical and cognitive fitness, higher levels of emotional
well-being, and more effective strategies for mastering gains
and losses of old age
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Young-Old, Old-Old, Oldest-Old
The Oldest-Old:
Are mostly female, widowed, and living alone
Are usually hospitalized at some time in last years of life
Die mostly alone in a hospital or institution
Are a heterogeneous, diverse group
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Biological Theories of Aging
Cellular Clock Theory: cells can divide a
maximum of 75-80 times; this places the
maximum human life span at 120–125 years of
age
Telomeres (bits of “junk” DNA)become shorter each
time a cell divides
Free-Radical Theory: people age because when
cells metabolize energy, the by-products
include unstable oxygen molecules, or free
radicals
Free radicals damage DNA and other cellular
structures
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Biological Theories of Aging
Mitochondrial Theory: aging is due to the decay of
mitochondria
Mitochondria: tiny bodies within cells that supply
essential energy for function, growth, and repair
Hormonal Stress Theory: aging in the body’s hormonal
system can lower resistance to stress and increase the
likelihood of disease
Prolonged, elevated levels of stress hormones are
associated with increased risks for many diseases
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The Aging Brain
On average, the brain shrinks 5% to 10% between the ages of
20 and 90
May result from a decrease in dendrites, damage to myelin
sheath, or the death of brain cells
Some areas of the brain shrink more than others
Shrinkage of the prefrontal cortex is linked with a decrease in
working memory and other cognitive activities
A general slowing of function in the brain and spinal cord
begins in middle adulthood and accelerates in late adulthood
Aging has been linked to a reduction in the production of
certain neurotransmitters
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The Adapting Brain
As the brain ages, it adapts in several ways:
Neurogenesis: the generation of new neurons throughout
the life span
Dendrite growth increases from the 40’s to 70’s
Older brains rewire to compensate for losses
Hemispheric lateralization can decrease; may improve
cognitive functioning
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The Immune System
The immune system declines in functioning with age
Extended duration of stress; diminished restorative
processes
Malnutrition involving low levels of protein
Exercise improves the immune system, and influenza
vaccination is very important for older adults
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Physical Appearance and Movement
Wrinkles and age spots become more noticeable
People get shorter with aging due to bone loss in their
vertebrae
Weight typically drops after we reach age 60; likely because
we lose muscle
Older adults move more slowly than young adults
Exercise and appropriate weight lifting can help reduce these
declines
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Physical Appearance and Movement
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Physical Appearance and Movement
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Sensory Development
Vision:
Decline in vision becomes more pronounced
Adaptation to dark and driving at night becomes
especially difficult
Decline may be the result of a reduction in the quality or intensity
of light reaching the retina
Color vision may decline as a result of the yellowing of
the lens of the eye
Depth perception declines in late adulthood
Decrease in contrast sensitivity
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Sensory Development
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Sensory Development
Diseases of the Eye:
Cataracts: a thickening of the lens of the eye that causes
vision to become cloudy, opaque, and distorted
Glaucoma: damage to the optic nerve because of the
pressure created by a buildup of fluid in the eye
Macular Degeneration: deterioration of the macula of
the retina, which corresponds to the focal center of the
visual field
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Sensory Development
Hearing:
Hearing impairments are typical in late adulthood
15% of the population over age 65 is legally deaf
Usually due to degeneration of the cochlea
Some (but not all) hearing problems can be corrected by hearing aids
Smell and Taste:
Smell(hyponosmia) and taste (hypogeusia) losses typically begin about
age 60
Less decline in healthy older adults
Often leads to a desire for more seasoned foods
Touch and Pain:
Slight decline in touch sensitivity with age
Older adults are less sensitive to pain
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The Circulatory System and Lungs
Cardiovascular disorders increase in late adulthood
Rise in blood pressure can be linked with illness,
obesity, anxiety, stiffening of blood vessels, or lack of
exercise
Lung capacity drops 40% between the ages of 20 and
80, even without disease
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Sexuality
Orgasm becomes less frequent in males with age
Many older adults are sexually active as long as they are
healthy
Older adults who do not have a partner are far less likely to be
sexually active than those who have a partner
Various therapies have been effective for older adults who
report sexual difficulties
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Sexuality
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Health Problems
Probability of having some disease or illness increases with
age
Arthritis is the most common
Hypertension is the second most common
Older women have a higher incidence of arthritis,
hypertension, and visual problems than older men
Older men are more likely than women to have hearing
impairments
Lifestyle and social and psychological factors are linked to
health in older adults
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Health Problems
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Health Problems
Nearly 75% of older adults die from heart disease,
cancer, or cerebrovascular disease (stroke)
Ethnicity is linked with death rates of older adults
African Americans have high death rates for stroke, heart
disease, lung cancer, and female breast cancer
Asian Americans and Latinos have low death rates for these
diseases
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Health Problems
Arthritis: an inflammation of the joints accompanied
by pain, stiffness, and movement problems
Common in older adults
Symptoms can be reduced with:
Use of some drugs like aspirin
Range-of-motion exercises
Weight reduction
Joint replacement in extreme cases
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Health Problems
Osteoporosis: extensive loss of bone tissue
Affects women more often than men
Can be prevented by:
Eating calcium-rich foods and vegetables
Having a regular exercise program
Medication
Accidents: 7th leading cause of death in older adults
Healing and recuperation are slower in older adults
Exercise programs can reduce risks
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Substance Abuse
Medications can increase the risks associated with consuming
alcohol or other drugs
Majority of U.S. adults 65 and older completely abstain from
alcohol
Substance abuse among older adults may be an “invisible
epidemic”
Late-Onset Alcoholism: onset of alcoholism after the age of 65
Often related to loneliness, loss of a spouse, or a disabling
condition
Moderate drinking of red wine is linked to better health and
increased longevity
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Exercise, Nutrition, and Weight
Exercise:
Active adults are healthier and happier
Benefits:
Linked to increased longevity
Related to prevention of common chronic diseases
Associated with improvement in the treatment of many
diseases
Can optimize body composition and reduce the decline in
motor skills as aging occurs
Reduces the likelihood that older adults will develop mental
health problems
Linked to improved brain and cognitive functioning
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Exercise, Nutrition, and Weight
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Exercise, Nutrition, and Weight
Nutrition and Weight:
Some older adults restrict their dietary intake in a way
that may be harmful to their health
Decreased snacking between meals may contribute to
harmful weight loss
Calorie restriction has been proven to extend the life span
of certain animals, but it is not known if this works in
humans
New research suggests that antioxidants may help slow
the aging process and possibly prevent some diseases
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Exercise, Nutrition, and Weight
Other factors such as exercise, better health practices,
and good nutritional habits may be actual cause of
positive correlation between vitamin intake and slower
aging, but more research needs to be done
There is now more interest in the possible link between
vitamins and cognitive performance in older adults
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Health Treatment
Some studies show older adults in the U.S. receive the
recommended medical care only half the time
Probability of being in a nursing home or other extendedcare facilities increases with age
The quality of these facilities varies and is a source of concern
Over 33% fail to meet minimum federal standards
Many specialists recommend alternatives, such as home
health care, day-care centers, and preventative medicine
clinics
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Health Treatment
Patient’s feelings of control and self-determination are
important for health and survival in nursing homes
Coping skills may reduce stress-related hormones,
improving overall health
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