Chapter 17


Physical and Cognitive Development

in Late Adulthood





Chapter Outline


            Old age used to be equated with loss:  loss of brain cells, loss of intellectual capabilities, loss of energy, loss of sex drive.

            GERONTOLOGISTS, specialists who study aging, now see late adulthood as a period of considerable diversity in which people change:  growth in some areas, decline in others.

            Late adulthood begins at 60 and ends at death.

            We cannot define old age by chronological years alone; we must also take into account people’s physical and psychological well-being, their functional ages.

            Some researchers divide aging people into three groups.

            The young old are healthy and active.

            The old old have some health problems and difficulties.

            The oldest old are frail and need care.

            Physical Development in Late Adulthood

            Aging:  Myth and Reality

            Because people are living longer, late adulthood is increasing in length.

            In 1900, only 6 percent of the population was age 60 or older.

            By 1990, more than 17 percent are 60 or older.

            Projections into the year 2050 estimate that almost 25 percent of the population will be over 65.

            The fastest growing segment of the population is what is termed the oldest old, people who are 85 or older.  This group's size has nearly doubled in the last 20 years.

            This trend is occurring in every developed country in the world.

            AGEISM, prejudice and discrimination directed at older people, is manifested in several ways.

            Negative attitudes about older people, especially about competence and attractiveness.

            Job discrimination

            Asians and Native Americans revere older people.

            Identical behavior by an older person and a younger person is interpreted differently.

            People talk baby talk to persons in nursing homes.

            Most negative views are based on misinformation.

            Physical Transitions in Older People

            PRIMARY AGING is aging that involves universal and irreversible changes that, due to genetic programming, occur as people get older.

            SECONDARY AGING is changes in physical and cognitive functioning that are due to illness, health habits, and other individual differences, but which are not due to increased age itself and are not inevitable.

            One of the most obvious outward signs of aging is the hair.

            gray or white


            The face and other parts of the body become wrinkled as the skin loses elasticity and collagen, the protein that forms the basic fibers of body tissue.

            People may shrink as much as 4 inches.

            cartilage in backbone becomes thinner

            women are most susceptible if they have OSTEOPOROSIS, a condition in which the bones become brittle, fragile, and thin, often brought about by a lack of calcium in the diet.

            25 percent of women over 60 have osteoporosis.

            Osteoporosis is the primary cause of broken bones.

            Osteoporosis is largely preventable with sufficient calcium and exercise.

            Women, especially in Western cultures, suffer from the double standard for appearance, where women who show signs of aging are judged more harshly than are men.

            Women are more likely to dye their hair.

            Women are more likely to have plastic surgery.

            Significant changes also occur in the internal functioning of the organ systems.

            The brain becomes smaller and lighter with age.

            There is a reduction of blood flow to the brain.

            The space between the skull and the brain doubles from age 20 to 70.

            The number of neurons, or brain cells, declines in some parts of the brain, though not as much as was once thought.

            Because of hardening of the arteries and shrinking of blood vessels, a 75-year-old's heart pumps less than three-quarters of the blood it pumped during early adulthood.

            The efficiency of the respiratory system declines with age.

            The digestive system produces less digestive juice and is less efficient in pushing food through the system (result = more constipation).

            Older adults’ reaction time slows significantly.

            The PERIPHERAL SLOWING HYPOTHESIS suggests that overall processing speed declines in the peripheral nervous system (spinal cord and brain).

            The GENERALIZED SLOWING HYPOTHESIS is the theory that processing in all parts of the nervous system, including the brain, is less efficient.

            Older people have more accidents.

            Decision process is slowed down.

            Old age brings a distinct declining in the sense organs of the body.


            Lens becomes less transparent and the pupils shrink.

            The optic nerve becomes less efficient.

            Distant objects become less acute.

            More light is needed to see and it takes longer to adjust to a change from light to darkness and vice versa.

            Driving at night becomes difficult.

            Reading becomes more of a strain and eye strain occurs more easily.

            Cateracts, cloudy or opaque areas of the lens of the eye that interfere with passing light, frequently develop.

            Cataracts can be surgically removed.

            Intraocular lens implants can replace old lens.

            Glaucoma occurs when pressure in the fluid of the eye increases, either because the fluid cannot drain properly or because too much fluid is produced.

            Glaucoma can be corrected with drugs or surgery.

            It must be detected early enough.

            The most common cause of blindness in people over the age of 60 is age-related macular degeneration (AMD), which affects the macula, a yellowish area of the eye located near the retina at which visual perception is most acute.


            30 percent of adults between 65 and 74 have some hearing loss.

            50 percent of adults over 75 have hearing loss.

            High frequencies are the hardest to hear.

            Hearing aids would be helpful 75 percent of the time but only 20 percent of people wear them.

            They are imperfect and amplify all sounds so it is difficult to discern conversations.

            There is a stigma attached to wearing a hearing aid.

            Because they cannot hear, some people withdraw from society because they feel left out and lonely.

            Taste and smell

            Both senses become less discriminating in old age.

            Due to decline in taste buds on tongue.

            Olfactory bulbs in the brain shrink and reduce the ability to smell.

            People eat less and get poor nutrition.

            Older people may oversalt their food and develop hypertension, or high blood pressure.

            Health and Wellness in Late Adulthood

            Health Problems in Older People:  Physical and Psychological Disorders

            The leading causes (three-fourths of all deaths) of death in elderly people are:  heart disease, cancer, and stroke.

            Most older people have at least one chronic, long-term condition.

            Arthritis, an inflammation of one or more joints, is common, striking around half of older people.

            Approximately one-third of older people have hypertension, or high blood pressure.

            15 to 25 percent of those over age 65 show some symptoms of psychological malady.

            Depression is characterized by intense sadness, pessimism, and hopelessness.

            May be a result of cumulative losses in life.

            Declining health may contribute.

            Some psychological problems such as anxiety may be caused by inappropriate drug doses.

            The most common mental disorder of old people is DEMENTIA, a broad category covering several diseases, each of which includes serious memory loss accompanied by declines in other mental functioning.

            Signs are declining memory, lessened intellectual abilities, and impaired judgment.

            Less than 2 percent of people between the ages of 60 and 65 have it; percentages double every 5 years after 65.

            One-third of those over 85 suffer from some sort of dementia.

            The most common form of dementia is ALZHEIMER'S DISEASE, which is a progressive brain disorder that produces loss of memory and confusion.

            Alzheimer's kills 100,000 people a year.

            19 percent of people 75 to 84 have Alzheimer’s and almost 50 percent of people over 85 are affected.

            If current trends continue, by the year 2040, almost 14 million Americans over 85 will be victims.

            The symptoms appear gradually.

            Unusual forgetfulness.

            Trouble recalling particular words during conversation.

            First recent memory goes, then older memories.

            Eventually, total confusion, inability to speak intelligibly or to recognize family and friends.

            Toward the end, loss of muscle control and  confinement to bed.

            Alzheimer’s occurs when production of the protein beta amyloid precursor protein, a protein that normally helps the production and growth of neurons, goes awry.

            The brain shrinks, and several areas of the hippocampus and frontal and temporal lobes deteriorate, certain neurons die, and create a lack of acetylcholine.

            No known triggers are understood to cause Alzheimer's, it runs in families.

            Diet and high blood pressure may increase susceptibility.

            Viruses and low cognitive ability may also be implicated.

            There is no cure for Alzheimer’s.

            Several drug treatments appear promising:  Tacrine, or Cognex, which are forms of acetylcholine, in addition to anti-inflammatory drugs and vitamins C and E.

            Only helps about 20 percent.

            No drug treatment is totally effective.

            Because all Alzheimer patients are eventually bedridden, many end their lives in nursing homes.

            Wellness in Late Adulthood:  The Relationship Between Aging and Illness

            Genetic predisposition, lifestyle, economic well-being, and psychological factors play important roles in people’s susceptibility to illness.

            People can do specific things to enhance their physical and psychological well-being and their longevity – their active life spans -- during old age.

            Eat a proper diet.


            Avoid threats to health, such as smoking.

            Sex in Old Age:  Use It or Lose It

            Evidence suggests that people are sexually active well into their 80s and 90s.

            Good physical and mental health are necessary.

            Previous sexual activity increases the desire for sex - "Use it or lose it."

            Studies show that 43 percent of men and 33 percent of women over age 70 masturbate.

            Two-thirds of men and women over age 70 had sex with their spouses on average about once a week.

            It takes men longer to get an erection and women's vaginas become thin and inelastic, and they produce less lubrication.

            Approaches to Aging:  Why is Death Inevitable?

            GENETIC PREPROGRAMMING THEORIES OF AGING suggest that our body's DNA genetic code contains a built-in time limit for the reproduction of human cells.

            One theory is that genetic material has a "death gene" that is programmed to direct the body to deteriorate and die.

            Another theory is that genetic instructions for running the body can be read only a certain number of times before they become illegible.

            WEAR-AND-TEAR THEORIES OF AGING argue that the mechanical functions of the body simply wear out with age.

            Some theories say that the body's constant manufacture of energy to fuel its activities creates by-products, which eventually reach such high levels that they impair the body's normal functioning.

            Free radicals, electrically charged atoms, are produced in the cells and may cause negative effects on other cells.

            This is a more optimistic theory, which suggests that longevity can be extended by eliminating the toxins produced by the body.

            LIFE EXPECTANCY, the average age of death for members of a population, has been steadily increasing.

            In 1776, the average life expectancy was 35.

            In 1900, the average life expectancy was 47.

            For a person born in 1980 life expectancy is 74.

            By 2050, the average life expectancy is predicted to be 80.

            Health conditions are better.

            Many diseases are wiped out or better controlled through medicine.

            People's working conditions are better.

            We are working on improving environmental conditions.

            The maximum human lifespan is believed to hover around 120.

            To extend the maximum lifespan would probably take genetic alterations.

            Developmental Diversity:  Gender, Race, and Ethnic Differences in Average Life Expectancy:  Separate Lives, Separate Deaths

            The average Caucasian in the U.S. is likely to live 76 years.

            The average African American is likely to live 71 years.

            The average Japanese is likely to live 79 years.

            The average Gambian is likely to live less than 45 years.

            A male born in the U.S. is most likely to live 73 years.

            A female born in the U.S. is most likely to live 80 years.

            Women's hormones (estrogen and progesterone) protect them from heart attacks.

            Women experience less stress in the workforce than men.

            Women may eat more healthy diets than men.

            Men smoked more in the past.

            Racial disparities may reflect better eating habits (Japanese) and lower socioeconomic well-being (African-Americans).

            Cognitive Development in Late Adulthood

            Intelligence in Older People

            The notion that older people become less cognitively adept arose from misinterpretations of research evidence.

            Cross-sectional research does not take into account cohort effects, influences attributable to growing up in a particular era.

            Longitudinal studies suffer from practice effects and sample attribution.

            Recent research (by K. W. Schaie) uses cross-sequential methods, which combine cross-sectional and longitudinal methods.

            Included 500 subjects (ages 20 to 70 in 5 year intervals).

            Tested every 7 years.

            More subjects added to create a total of 5,000.

            Results show no uniform pattern of adulthood age-related changes across all intellectual abilities.

            Some abilities (fluid intelligence) decline, starting at age 25.

            Other abilities (crystallized intelligence) stay steady or increase.

            For some, there were cognitive declines in all abilities by age 67.

            These declines were minimal until age 80.

            At age 81, less than half showed consistent declines.

            There were individual differences in the patterns of changes.

            For some, intellectual skills begin to decline in their 30s.

            Others show no decline until their 70s.

            One-third of those in their 70s score higher than the average young adult.

            Certain environmental and cultural factors are related to greater or lesser degrees of intellectual decline.

            Lesser declines are associated with good health, high SES, involvement in an intellectually stimulating environment, a flexible personality, being married to a bright spouse, maintenance of good perceptual processing speed, and feeling self-satisfied with one's accomplishments in middle and early old age.

            Schaie and Willis taught people whose reasoning and spatial skills had declined a variety of skills.  More than half showed significant improvement.

            Such PLASTICITY, or modifiability of behavior, suggests that there is nothing fixed about the changes that may occur in intellectual abilities during late adulthood ("Use it or lose it").

            Memory:  Remembrance of Things Past – and Present

            Memory losses occur primarily to episodic memory, which relates to specific life experiences.

            Semantic memories (general knowledge and facts) and implicit memories (memories about which people are not consciously aware) are largely unaffected by age.

            Short-term memory declines gradually until age 70, when it becomes more pronounced.

            Information presented quickly and verbally is forgotten sooner.

            New information is more difficult to recall perhaps because it is not processed as efficiently.

            People's AUTOBIOGRAPHICAL MEMORY, memories of information about one's own life, frequently follows the Pollyanna principle, in which pleasant memories are more likely to be recalled than unpleasant memories.

            People recall material that "fits" their current self-view.

            Particular periods of life are remembered more easily than others.

            70-year-olds recall their 20s  and 30s best.

            50-year-olds recall their teenage years and their 20s best.

            Changes in memory focus on three categories.

            Environmental factors



            motivation lower

            Information-processing deficits

            inability to inhibit irrelevant information and thoughts declines

            speed of processing declines

            difficulty paying attention and organizing information

            less efficient retrieval methods

            Biological factors

            brain and body deterioration

            especially frontal lobes

            Continuation of education in old age can improve cognitive skills.




Key Terms and Concepts




Primary aging

Secondary aging


Peripheral slowing hypothesis

Generalized slowing hypothesis


Alzheimer’s disease

Genetic preprogramming theories

Of aging

Wear-and-tear theories

Life expectancy


Autobiographical memory