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Learning Objective Questions (items marked *** are required objectives)

After completing Chapter 17, students should be able to:

17.1            ***What factors contribute to life expectancy and longevity?

17.2            ***What variables contribute to individual differences in health among older adults?

17.3            How does the brain change in late adulthood?

17.4            What changes happen in the sensory organs?

17.5            ***How do theorists explain biological aging?

17.6            What are the behavioral effects of changes in the various body systems of older adults?

17.7            ***What is Alzheimer’s disease, and how does it differ from other dementias?

17.8            What does research suggest about depression among older adults?

17.9            What kinds of memory differences distinguish older and younger adults?

17.10        ***What do theory and research on wisdom and creativity reveal about cognitive functioning in late adulthood?




The scientific study of aging is known as gerontology.  For many years, gerontologists thought about old age almost exclusively in terms of decline and loss.  Perspectives on the later years, however, are rapidly changing, and late adulthood is now thought of as a period of tremendous individual variability rather than one of universal decline.


Life Expectancy and Longevity


17.1     ***What factors contribute to life expectancy and longevity?


Trends in Life Expectancy

Life expectancy in the industrialized world these days is far greater than in the past.  Life expectancy is strongly influenced by the fact that the highest death rates in the entire human lifespan are found in the first few years of life.  Thus, the increases in average life expectancy that have occurred over the pat 7 or 8 decades result from improvements in nutrition, health care, and general living conditions for pregnant women, infants, and young children.


In the U.S., the average 65-year-old man lives to about age 82, but once a man reaches 85, he is likely to live to be 91.  Life expectancy among women is even longer.  The average 65-year-old woman lives to the age of 85, and the average 85-year-old woman can expect to live to over 92.  Because of these sex differences, there are more elderly women than there are men.


Life expectancy varies by racial group as well.  In general, 65- to 74-year-old white Americans have longer life expectancies than African Americans, perhaps because of different rates of cancer and other diseases.  By age 75, however, the life expectancies of white Americans and African-American elders are essentially equivalent.



Gerontologists divide the later years into the young old (60 to 75), the old old (75 to 85), and the oldest old (85 and up).  The oldest old are the fastest growing segment of the population in the U.S. at present, which means that terms such as octogenarian (a person in her 80s) and centenarian (a person over 100 years of age) will be used fare more often than in the past.




17.2     ***What variables contribute to individual differences in health among older adults?


The majority of older adults do not suffer from ailments that seriously impair their day-to-day functioning.  Moreover, the inevitable physical declines that are associated with aging do not seem to decrease older adults’ satisfaction with their lives.


Self-Rated Health

A majority of older adults regard their health as good.  This contradicts stereotypes of old age as a period of illness, but the proportions of elderly with good health are a great deal lower than the equivalent proportions for young and middle-aged adults.  Thus, health is the single largest factor determining the trajectory of an adult's physical or mental status over the years beyond 65.  A majority of older adults have emotional resiliency and are able to maintain an optimistic view of themselves and their lives in the face of growing physical challenges.  This optimistic view seems to help protect them against the long-term effects of serious threats to health such as strokes.  Those who are already suffering from one or more chronic diseases at 65, show far more rapid declines than do those who begin late adulthood with no disease, in part as a result of the disease process itself.


Limitations on Activities

Gerontologists generally define disability as a limitation in an individual’s ability to perform certain socially defined roles and tasks, particularly self-help tasks and other chores of daily living.  Daily living tasks are grouped into two categories:

§         Activities for daily living, or ADLs, include bathing, dressing, using the toilet, and so forth.

§         Instrumental activities of daily living, or IADLs, include activities that are more intellectually challenging, such as managing money.


Proportions of older adults with disabilities have declined in recent years.  Nearly half of those over 85 report at least some level of difficulty performing some basic daily life activities, but this means that half of these eldest adults do not have such problems.


Disability rates increase dramatically as elders get older.  Among those over the age of 80, nearly three-quarters suffer from some kind of disability and more than half require help with at least one ADL.  Consequently, the increase in their numbers means that the population of frail elderly, older adults who cannot care for themselves, is also likely to grow significantly.


Chronic Health Conditions

The prevalence of chronic health conditions increases with age.  The most common of these conditions are hypertension, also known as high blood pressure, followed by arthritis, inflammation in the joints that causes pain and stiffness.  Not everyone with these problems is disabled, but the risk of some kind of functional disability is two to three times higher among elders who suffer from these diseases than among those who do not.


Racial and Ethnic Differences

Among ethnic minorities, as among white Americans, individual variability in old age is the rule rather than the exception.  Averages in life expectancy and disabling conditions differ across groups, but a majority of elders rate their health as good to excellent.  The one exception is African- American men over age 85.  Moreover, the correlations between health habits and health status in adulthood are just as applicable to minorities as to whites.  Thus, improved diet, increased physical activity, and treatment of chronic ailments can potentially benefit elders of any race or ethnic group.



Some general tendency to live a long life is clearly inherited.  Identical twins are more similar in length of life than are fraternal twins, and adults whose parents and grandparents were long-lived are also more likely to live longer.


Health Habits

The same health habits that are important predictors of longevity and health in early adulthood continue to be significant predictors in late adulthood.  Perhaps the most crucial variable is physical exercise, which has been clearly linked not only to greater longevity but also to lower rates of diseases such as heart disease, cancer, osteoporosis, diabetes, gastrointestinal problems, and arthritis.  Those who exercise regularly maintained better physical functioning, were less likely to die, and were less likely to be in a nursing home.  It isn’t just that healthy adults are more likely to exercise, but exercise keeps people healthier.


Physical exercise also seems to help maintain higher levels of cognitive performance among the elderly.  If anything, physical exercise seems to be even more important in the later years than at earlier ages. 


A person’s eating pattern may turn out to be the most important health habit of all when it comes to aging.  Recommendations about the contributions of a healthy diet to one’s health are familiar, but recent findings suggest that calorie restriction may be equally important.  A form of calorie restriction called alternate day fasting also appears to moderate the effects of physical aging.  Calorie restriction and alternate day fasting are believed to influence aging and longevity by reducing an individual’s overall metabolic rate.


PHYSICAL CHANGES (pp. 490-496)

The Brain and Nervous System


17.3     How does the brain change in late adulthood?


There are four main changes in the brain during the adult years:  a reduction of brain weight, a loss of gray matter, a loss of density in the dendrites, and slower synaptic speed.  The most central of these changes is the loss of dendritic density.  The loss of dendrites in middle and late adulthood does not seem to be the same type of pruning as in infancy and childhood.  Rather, it appears to be a decrease in useful dendritic connections.


Experience as well as aging is involved in the loss of dendritic density.  Across the years from 60 to 90, adults with higher levels of education show significantly less atrophy of the cerebral cortex than do those who have fewer years of schooling.  The brains of well and poorly educated elderly adults do not differ in areas that are less involved in academic learning than the cerebral cortex is.  This suggests that education itself is the cause of the reduced atrophying rather than some general factor, such as socio-economic status, that is coincidentally related to education.


Dendritic loss also results in a gradual slowing of synaptic speed, with consequent slowing of reaction time in many everyday tasks.  Neural pathways are redundant enough that it is nearly always possible for a nerve impulse to move from neuron A to neuron B, or from neuron A to some muscle cell.  Neurologists usually refer to this redundancy as synaptic plasticity.  With the increasing loss of dendrites, the shortest route may be lost, so plasticity decreases and reaction time increases.


There is also a loss of neurons themselves, but the number of cells lost is so insignificant and there are so many redundancies in the nervous system that there is little impact.  Only when significant interconnectivity is lost, which occurs as dendrites shrink in number, does "computational power" decline and symptoms of old age appear.


The Senses


17.4     What changes happen in the sensory organs?



In addition to presbyopia (farsightedness), vision in old age is affected by a variety of other body changes.

§         Blood flow to the eye decreases resulting in an enlarged "blind spot" on the retina and a reduced field of vision.

§         The pupil does not widen or narrow as much or as quickly resulting in more difficulty seeing at night and responding to rapid changes in brightness.

§         A significant minority of older adults suffer from diseases of the eye that further diminish visual acuity and adaptability.

Collectively, these changes mean that many older adults must adapt to significant impairment of vision.  Vision loss has a greater negative effect on an elderly adult's sense of well being than on a middle-aged adult.



Wear and tear on the auditory system results in some hearing loss (presbycusis) beginning in middle adulthood, but these gradual losses do not typically add up to functionally significant loss until late adulthood.  Auditory problems, unlike many other disabilities of old age, are more likely to be experienced by men than by women.


Hearing difficulties of persons in late adulthood have several components:

§         Loss of ability to hear high-frequency sounds.

§         Difficulties in word discrimination.

§         Problems hearing under noise conditions.

§         Tinnitus, a persistent ringing in the ears.


Even mild hearing loss can pose communication problems in some situations.  Mild and moderate hearing losses, even if it is corrected with a hearing aid, are not correlated with measures of general social, emotional, or psychological health among elderly adults.  It is only when the loss is severe that there is an increase in social or psychological problems, including heightened rates of depression.


Presbycusis and other changes in hearing seem to result from gradual degeneration of virtually every part of the auditory system.  Older adults secrete more ear wax, the bones of the middle ear become more calcified and less elastic, the cochlear membranes of the inner ear become less flexible and less responsive, and the nerve pathways to the brain show some degeneration.


Taste, Smell, and Touch

The ability to taste the four basic flavors (salty, bitter, sweet, and sour) does not seem to decline over the years of adulthood.  Other changes in the taste system affect older adults, however, such as less saliva, producing a "woolly mouth" for some.  Many elders report that flavors seem blander than in earlier years, leading them to prefer more intense concentrations of flavors, such as sweetness, but this may be a result of a loss of the sense of smell rather than the loss of the sense of taste.


The sense of smell clearly deteriorates in old age.  The loss of sensitivity to odors is far greater among elderly men than women.  Just as is true of hearing loss, the loss of the sense of smell seems to have an environmental component.  Specifically, both men and women who worked in factories (where, presumably, they were exposed to more pollutants) show much greater losses of smell in old age than do those who worked in offices.


The skin of elderly adults is also less responsive to cold and heat.  The loss of sensitivity occurs in a pattern that is a reversal of the proximodistal principle of growth.  In other words, the extremities, usually the feet, are the first body parts that decline in sensitivity.  Consequently, elderly people are less able to benefit from the potential comforts associated with physical stimuli.  For an elderly person to be able to feel a warm bath, the water temperature may have to be so high that it will burn the skin.


Theories of Biological Aging


17.5     ***How do theories explain biological aging?


The most current theories of physical aging emphasize the basic cellular processes, which appear to change with age in specific ways that reduce the efficiency of cellular functioning.


The Hayflick Limit

Species vary widely in how long, on average, individuals live.  These differences have persuaded some biologists that there may be a universal genetic process that triggers age-related declines and limits the lifespan.  For humans, the maximum life span seems to be about 110 or 120 years.  Biologist Leonard Hayflick observes that embryo cells placed in nutrient solution will divide only a fixed number of times, after which the cell colony degenerates.  Human embryo cells double about 50 times; those from Galapagos tortoise double roughly 100 times; chicken cells double only about 25 times.  Furthermore, cells taken from human adults will double only about 20 times, fewer times than the embryo cells, as if they have already "used up" some of their genetic capacity.  The theoretical proposal that emerges from such observations is that each species has some Hayflick limit, after which cells simply no longer have any capacity to replicate themselves.


Hayflick's argument is strengthened by the recent discovery that each chromosome in the human body has, at its tip, a string of repetitive DNA called telomeres.  Among other functions, telomeres appear to serve as a kind of time-keeping mechanism for the organism, raising the possibility that there may be a crucial minimum number of telomeres.  When the total falls below that number, then disease or death comes fairly quickly.


Genetically Programmed Senescence

Senescence is the gradual deterioration of body systems that happen as organisms age.  The programmed senescence theory suggests that age-related physical declines result from species-specific genes for aging.  Evolutionary theorists argue that programmed senescence prevents older, presumably less fit, individuals from becoming parents at an age when they are unlikely to be able to raise offspring to maturity.  The idea is that the aging genes are equipped with some kind of built-in clock that prevents the genes from having an effect when people are in their reproductive years, but switches them on once the reproductive peak has passed.


Repair of Genetic Material and Cross-Linking

Another explanation focuses on the cell's ability to repair breaks in DNA.  Breaks in DNA are common events, resulting from unknown metabolic processes.  Because the organism is apparently unable to repair all the damage, the accumulation of unrepaired breaks results, over time, in loss of cellular function, and the organism ages.


A related theory focuses on another cellular process called cross-linking, which occurs more often in cell proteins in older than in younger adults.  Cross-linking occurs when undesirable bonds form between proteins or fats.  In skin, and in connective tissue, for example, two proteins called collagen and elastin form cross-linkages, either between molecules or within a given protein molecule.  The resulting molecules cannot assume the correct shape for proper function, producing various effects such as wrinkling of the skin and arterial rigidity.


Free Radicals

A third type of cellular process that may contribute to aging relates to the body's ability to deal with free radicals.  Free radicals, which are molecules or atoms that possess an unpaired electron, are a normal by-product of body metabolism as well as exposure to certain substances in food, sunlight, X-rays, or air pollution.  These radicals, especially the subgroup called oxygen free radicals, enter into many potentially damaging chemical reactions, resulting in irreparable molecular damage that accumulates with age.  Oxidation reactions caused by free radicals can damage cell membranes, thereby reducing the cell's protection against toxins and carcinogens.


Research on diet variations points to the possibility that some foods, especially food high in fat, promote the formation of oxygen free radicals, while others, referred to as antioxidants, inhibit it or produce chemical processes that help the body defend against free radicals.  Foods high in vitamins C and E and beta carotene (vitamin A) all belong to the latter group.  Some studies show that people who maintain diets higher in antioxidants or who take regular supplements of vitamin E or beta carotene live somewhat longer and have lower rates of heart disease.


Such findings do not mean that age-related problems are caused by antioxidant deficiencies.  Moreover, some studies suggest that free radicals may not contribute as much to physical aging as researchers once believed.  Nevertheless, studies showing association between antioxidants and improvements in health support the general notion that many of the effects of aging can be modified and perhaps prevented.


Terminal Drop

Some theorists claim that physical and mental declines in old age are actually part of the dying process.  The terminal drop hypothesis asserts that all adults retain excellent physical and mental function until just a few years before death, at which time there are significant declines in all functions.  Longitudinal research, however, suggests that decline in most functions are gradual across late adulthood.  Only changes in cognitive functions seem to fit the terminal drop pattern.


Behavioral Effects of Physical Changes


17.6     What are the behavioral effects of changes in the various body systems of older adults?


General Slowing

The biggest single physical effect of aging is a general sense of slowing down.  Dendritic loss at the neural level clearly contributes substantially to this general slowing, but other factors are also involved, including arthritic changes in the joints and loss of elasticity in the muscles.  Everything takes longer, even tasks that involve word skills.  The decline in the speed of nerve impulses may be responsible for age-related difficulties in translating thought into action.  General slowing of brain activity interferes with older adults' retrieval of the knowledge they need to accomplish the task and that they use behavioral feedback to compensate for mistakes.


Age-related physical changes add up to really significant differences in functioning in a complex motor activity like driving.  Young adults have more auto accidents than any other age group, primarily because they drive too fast.  Older adults, however, have more accidents per mile driven.  Other physical changes beyond general slowing contribute to driving problems in old age, such as the changes in the eyes, reduced range of motion in the neck, difficulties judging speed, and general increase in reaction time.


Changes in temperature sensitivity, together with general slowing, lead to increases in accidental burns.


Sleeping and Eating Patterns

A shift in sleep patterns in old age is a primary aging pattern.  Adults older than 65 typically wake up more frequently in the night and show decreases in rapid eye movement (REM) sleep, the sleep state in which dreaming occurs.  Older adults are also more likely to wake early in the morning and go to bed early at night.  Because their night's sleep is more often interrupted, older adults also nap more during the day in order to accumulate the needed amount of sleep.  These changes in sleep and activity patterns are presumed to be related to changes in nervous system functioning.


The ability of the brain to regulate appetite also changes with advancing age.  When you eat, your blood sugar rises, resulting in a chemical message to the brain that creates a sensation called satiety, the sense of being full.  The feeling of satiety continues until your blood sugar drops, at which time another chemical message is sent to the brain that causes you to feel hunger.  In older adults, the satiety part of the pattern seems to be impaired.  The result may be a feeling of hunger all the time that may cause overeating.


Motor Functions

The various physical changes associated with aging also combine to produce a reduction in stamina, dexterity, and balance.  The loss of stamina clearly arises in large part from the changes in the cardiovascular system, as well as from changes in muscles.  Dexterity is lost primarily as a result of arthritic changes in the joints.  Older adults also experience a gradual loss of balance, and are likely to encounter greater difficulty handling an uneven sidewalk or adapting their bodies to a swaying bus.  As a result, older adults fall more often.


Older adults also have more problems with fine-motor movements.  Such losses are small and gradual with respect to well-practiced skills such as handwriting.  Fine-motor activities that require learning a new pattern of movement, however, may be extremely difficult for elderly people.


Sexual Activity

Another behavior that is affected by the cumulative physical changes of aging is sexual behavior.  Research from both longitudinal and cross-sectional studies indicates that sexual activity declines from middle adulthood to late adulthood.  The decline in sexual activity in late adulthood doubtless has many causes.  The continuing decline in testosterone levels among men clearly plays some role, as does overall health.  There may also be some effect of social definitions that portray old age as an essentially asexual period of life.  On the other hand, while sexual activity may decline, despite the physical changes, many older adults continue to find pleasure in sexual activity.


MENTAL HEALTH (pp. 496-502))

The best-known mental health problems of old age are the dementias, a group of neurological disorders involving problems with memory and thinking that affect an individual's emotional, social, and physical functioning.


Alzheimer's Disease and Other Dementias


17.7     ***What is Alzheimer’s disease, and how does it differ from other dementias?


Alzheimer’s disease (technically known as dementia of the Alzheimer’s type) is a very severe form of dementia.  The early stages of Alzheimer's disease usually move very slowly, beginning with subtle memory difficulties, repetitions in conversations, and disorientation in unfamiliar settings.  Then memory for recent events begins to go.  Memory for long-ago events or for well-rehearsed cognitive procedures is often retained until late in the illness.  Eventually an individual with Alzheimer's disease may fail to recognize family members, may be unable to remember names of common objects or how to perform such routine activities as tooth brushing or dressing.  Some of those afflicted with Alzheimer’s have problems controlling their own emotions and display sudden bursts of  anger or even rage.  Others an increased level of dependency and clinginess to family or friends. Additionally, the incidence of depression among elders with Alzheimer’s disease may be as high as 40 percent.


Diagnosing and Treating Alzheimer’s Disease

Alzheimer’s disease can only be definitely diagnosed after a person has died.  At autopsy, the brains of Alzheimer’s victims are far more likely to contain extensive neurofibrilary tangles than the brains of individuals with other kinds of dementia.  Neurofibrilary tangles are stringy masses of tissue that appear to “clog” connections between neurons.  They are typically surrounded by deposits of proteins and other substances called plaques.


The difficulty involved in diagnosing Alzheimer’s disease is magnified by the fact that nearly 80% of elderly individuals complain of memory problems.  Researchers are currently looking for a set of predictors that may distinguish individuals who are in the process of developing Alzheimer’s from those who are suffering from the effects of normal aging.  A few indicators, such as the syndrome known as mild cognitive impairment, show promise.


A few drugs appear to slow down the progress of Alzheimer’s disease.  Training Alzheimer’s sufferers to use specific strategies for everyday memory tasks can improve their memories to some degree.


Heredity and Alzheimer's Disease

Genetic factors seem to be important to some, but not to all cases of Alzheimer’s.  Researchers have found a gene on chromosome 19 (apoliprotein E or ApoE) that controls production of a protein that is linked to Alzheimer’s disease.  When errors in the production of this protein occur, the dendrites and axons of neurons in the brain become tangled and, as a result, do not function as efficiently.  However, this gene does not act alone.  Many other genes combine with ApoE in ways researchers don’t yet fully understand to trigger the onset of the disease.


Even in families with very high prevalences of Alzheimer’s disease, ages of onset are highly variable.  Moreover, there were wide variations in the severity of the disease’s behavioral effects and in the length of time the victims lived once they developed Alzheimer’s.


Other Types of Dementia

Strictly speaking, dementia is a symptom and not a disease, and neurological research indicates that Alzheimer’s and non-Alzheimer’s dementias involve very different disease processes.  Signs of dementia frequently appear after a person suffers multiple small strokes, a condition called multi-infarct dementia.  The brain damage caused by such strokes is irreversible.  In contrast to most cases of Alzheimer’s disease, various forms of therapy—occupational, recreational, and physical—can improve victims’ functioning.


Dementia can also be caused by depression, cardiovascular disease, metabolic disturbances, drug intoxication, Parkinson's disease, hypothermia, multiple blows to the head (as among boxers), a single head trauma, some kinds of tumors, vitamin B12 deficiency, anemia, or alcohol abuse.  Many of these causes are treatable and it is critical to arrange for a careful differential diagnosis.


Group Differences in the Rates of Dementia

Evidence from studies from around the world is converging on the conclusion that somewhere between two and eight percent of all adults over age 65 show significant symptoms of dementia, and that two to five percent have Alzheimer's disease.  The rate of dementia rises rapidly among people in their 70s and 80s.




17.8     What does research suggest about depression among older adults?


The earliest studies of age differences in depression suggested that older adults were at higher risk than any other age group.  The full story, however, on depression in late adulthood is complex.


Prevalence and Risk Factors

Estimates of the prevalence of depression depend on how it is defined.  If depression is defined as the presence of any kind of depressive symptom, as many as a quarter of the old old and the oldest old suffer from depression.


The risk factors for depression among the elderly include the following:

§         inadequate social support

§         inadequate income

§         emotional loss

§         nagging health problems

§         health status (the strongest predictor)—the more disabling conditions older adults have, the more depressive symptoms they have

§         gender—depressed women outnumber men two to one among the elderly

§         poverty

§         education—poorly educated older adults are more likely to be depressed


Ethnic and Cultural Differences

Poverty and education account for only some of the ethnic differences in depression among older adults.  Other differences are explained by health status.  That is, on average, minorities have poorer health than whites in the U.S.; so, on average, most minority groups have higher rates of depression.

§         The prevalence of depressive symptoms in elderly Native Americans may be as high as 20 percent.  As a group, they suffer from chronic illnesses at higher rates, and those with the greatest number of physical limitations are the most depressed.

§         The rate of depression among Chinese-American and Mexican-American elders may also be near 20 percent.  Health problems are associated with depression, as with all groups.  Many of the older adults are recent immigrants to the U.S. and have poor English skills, putting them at a higher risk for depression.

§         The entire cluster of depressive symptoms appears to occur much less often in African Americans, even those who are the least healthy.  Some developmentalists attribute the lower rate to cultural differences.  Specifically, African Americans are more likely to view feelings of sadness as a spiritual issue rather than a mental health problem.  Religious faith and practice are associated with lower incidence of long-term depression in most ethnic groups, no matter what religion is considered.



Elderly white men are more likely to commit suicide than any other group; however, the overall age-related pattern of sex differences exists among minority groups as well (see Figure 16.6).  The reasons for this dramatic sex difference are not entirely clear.  Loss of economic status through retirement may be more troubling for men than for women.  Declining health may cause an elderly man to view himself as a burden on others.  The death of a spouse may be a factor in many male suicides.  Older women attempt suicide more often than older men do, but the men complete the act more often, mostly because they are more likely than women to choose violent methods such as firearms.


Therapy, Medication, and Prevention

Therapies for depression are the same for older adults as for those who are younger.  Psychotherapy is often recommended, especially interventions that help sufferers develop optimistic thought patterns.  Therapy appears to be most effective, however, when combined with antidepressant medications.  The appropriate use of antidepressant medication among the elderly is critical for at least two reasons.

§         Antidepressants may reduce the effectiveness of the life-sustaining drugs some older adults take.

§         Antidepressants are linked to an increased incidence of falls among the institutionalized elderly.


Social involvement may be important in preventing depression in the elderly.  Additionally, research on the connection between religion and depression suggests that caretakers can help elders avoid depression by supporting their spiritual needs.  Helping elders maintain religious faith and practice may be an important key to reducing depression rates.



Among the young old (ages 65 to 75), cognitive changes are still fairly small, and on a few measures, such as vocabulary knowledge, the young old show little or no average decline.  The old old and the oldest old, however, show average declines on virtually all measures of intellectual skill, with the largest declines on any measure that involves speed or unexercised abilities.




17.9     What kinds of memory differences distinguish older and younger adults?


Forgetfulness becomes more frequent with age, but the same basic rules seem to apply to memory processes among both older and younger adults: recognition is easier than recall, tasks that require speed are more difficult, and metamemory skills are important to memory function.  Older adults achieve scores on tests of memory accuracy that are very similar to those of younger adults, although they typically take longer to complete memory tasks and make more errors.


Short-Term Memory Function

One area in which researchers see significant late adulthood changes is in short-term, or working, memory capacity.  There is a limitation on the number of items a person can retain in her memory at once.  The more demands any given cognitive task makes on working memory, the larger the decline with age.  Patterns of age differences are not identical for all memory tasks.  Older adults typically perform more poorly than younger adults on tasks involving retrospective memory (recalling something in the past).  By contrast, older adults’ performance on prospective memory tasks (remembering to do something in the future) depends on the type of task involved.  Older adults outperform those who are younger on everyday memory tasks.


Strategy Learning

Older adults showed improvement after training in strategy learning, but their performance was poorer than that of younger adults.  These findings suggest that the learning process simply takes longer for older adults; however, when allowed more time, older adults' performance was more similar to that of younger participants.  Other findings suggest that the tendency to apply some cognitive strategies automatically may decline with age.


Everyday Memory

One common argument from those who take a more optimistic view of the effects of aging on cognitive functioning, is that older adults may be able to remember just as well as younger adults.  Older adults are simply less motivated to memorize lists of unrelated words given to them by researchers in a laboratory.  On virtually all "everyday" tasks—such as remembering the main points of a story or a newspaper article; recalling movies, conversations, grocery lists, or recipes; recalling the information from a medicine label; remembering whether some action has been performed; remembering where something was heard (called source memory); or remembering to do something in the future—older adults recall less well than younger adults.  Task-specific knowledge, however, seems to make a difference among the elderly.  Prior knowledge is the critical factor.


Preliminary Explanations

Neuroimaging studies show that age-related memory decline is associated with changes in the ratio of gray to white matter in the brain.  In addition, a reduction in the volume of the hippocampus is associated with memory deficits among the elderly.


Older adults take longer to register some new piece of information, encode it, and retrieve it.  Timothy Salthouse tested both reaction speed and memory or other cognitive skills in adults of various ages, and found that a very large portion of the age decline in memory can be accounted for simply by slower reaction times in older adults.  Some of the loss of speed is at the level of the central nervous system and not at some more peripheral level.  The physiological changes in neurons and the accompanying loss of nerve conductance speed may be the root cause of the changes in memory.  Most experts agree with Salthouse, but they also believe that speed is not the entire explanation.  There appear to be other factors as well, such as changes in attention strategies that lead to less effective processing of information.


Wisdom and Creativity


17.10   ***What do theory and research on wisdom and creativity reveal about cognitive functioning in late adulthood?


Theorists who study cognition in older adults have recently begun to ask whether elders might have some advantages over the young because of their accumulation of knowledge and skills.  In other words, older adults might be wiser.  Researchers do not agree on a common definition of wisdom, but most authors emphasize that it goes beyond mere accumulations of facts.  Wisdom reflects understanding of “universal truths” or basic laws or patterns; it is knowledge that is blended with values and meaning systems; it is knowledge based on the understanding that clarity is not always possible, that unpredictability and uncertainty are part of life.  A wise person, then, will have unusual insight into life problems and unusually good judgment or advice to offer.


The leading researcher on wisdom is Paul Baltes.  His technique for measuring wisdom involves stories about fictional characters who are trying to make some major life decision.  The stories are judged according to the following five criteria Baltes hypothesized to be central to wisdom as it relates to solving practical life problems:

§         factual knowledge

§         procedural knowledge

§         understanding relevance of context

§         understanding relevance of values

§         recognition that it is impossible to know in advance how any decision will ultimately affect one's life.

People's motivations, their backgrounds, and their own views must be considered to understand their decisions.


Virtually all theorists who have written about wisdom assume that it is more likely to be found in the middle-aged and the elderly.  Baltes found that young adults perform as well as older adults in response to the fictional dilemma task, and that intelligence and professional experience, rather than age, correlated with responses to the task.  His research seems to suggest that the popular idea that age and wisdom are associated is probably not true.  Wisdom does not appear to be a characteristic of the elderly that distinguishes them from other subgroups of adults.


Critics suggest that Baltes is simply measuring general cognitive ability rather than what is usually thought of as wisdom.  Nevertheless, Baltes' research has produced an important finding about wisdom and old age:  In contrast to performance on information-processing tasks, performance on wisdom tasks does not decline with age.  Moreover, the speed of accessing wisdom-related knowledge remains constant across adulthood.  Additionally, those adults singled out by their peers as wise are more likely to rank high in what Erikson called ego integrity and are more likely to show concern for humanity as a whole.


Enhanced creativity may also be an element of cognition in older adults.  Some highly creative individuals, especially composers and artists, reach their peak in late adulthood.  To describe the potential for creative work in the later years, a leading gerontologist, Gene Cohen, developed a four-stage theory of mid- to late-life creativity.  He believes that these phases apply to ordinary people who are more creative than others in their everyday lives as well as to "professional creators" such as composers and artists.

§         Around age 50, creative individuals enter a reevaluation phase, during which they reflect on past accomplishments and formulate new goals.  The reevaluation process, along with an increasing sense of time limitations, leads to an intensification of the desire to create and produce.

§         During the next stage, the liberation phase, individuals in their 60s become freer to create, because most have retired from everyday work.  Most are also more tolerant of their own failures, and thus are willing to take risks that they would not have taken at earlier ages.

§         In the summing up phase, creative people in their 70s have a desire to knit their accomplishments together into a cohesive, meaningful story.

§         In the encore phase, during the 80s and beyond, there is a desire to complete unfinished works or to fulfill desires that have been put aside in the past.