Late Adulthood: Biosocial Development

    * Ageism - A prejudice, the tendency to categorize & judge people solely on the basis of their 
chronological age. Ageism can target people of any age, old people are often stereotyped in this way.
    * The study of old age is Gerontology.
    * The study of populations, including descriptive statistics regarding age, sex, and other 
characteristics of various groups is called Demography.
    * The world's population over the age 65 is 7 percent and in the United States it is 13 percent.
    * The actual proportion of the elderly who are in nursing homes and hospitals is only 5 percent 
at any given time.
    * Dependency Ratio is the ratio of self-sufficient, productive adults to dependents-children 
and the elderly.
    * In most industrialized countries, the current dependency ratio, about two independent adults for 
every dependent person, is better than it has been for a century, as a result of the declining birth 
rate since 1970 and the small cohort just entering late adulthood.
    * What will happen as more and more people live past working age?  Some experts warn about 
the potentially catastrophic consequences of increased costs for the medical care of the elderly 
and of decreased publics funds for the needs of the younger generation.
    * Only about 5 percent of the elderly live in nursing homes, about another third live alone, about 
20 percent live with grown children, and the rest live with a husband or wife.
    * Young-old are healthy, vigorous, financially secure older adults who are well integrated into 
the lives of their families and their communities.
    * Older adults who suffer from physical, mental, or social deficits are old-old.
    * Oldest-old are elderly adults who are dependent on others for almost everything, requiring 
supportive service such as nursing homes and hospital stays. 

 Primary Aging

    * The universal & irreversible physical changes that occur to living creatures, as they grow 
older is called primary aging.
    * Primary aging includes all the processes of senescence.
    * Every part of the body slows down, from speech to heart rate, from speed of walking to 
speed of thinking, from reaction time to reading time.
    * Every body system also becomes less efficient with age, with a gradual reduction in 
capacity and organ reserve.
    * Appearance changes as aging occurs, such things as skin, hair, body height, body shape, 
and body weight.
    * The skin is often the first sign: It becomes drier, thinner, and less elastic; wrinkles and visible 
blood vessels and pockets of fat appear.
    * The hair also undergoes obvious changes, growing thinner and grayer and, in many people, 
eventually becoming white or disappearing completely.
    * Most older people are more than an inch shorter than they were in early adulthood, because 
the vertebrae begin settling closer together in middle age.
    * Body shape is affected by redistribution of fat, disappearing from the arms, legs, and upper 
face and collecting in the torso and the lower face.
    * Older adults often weigh less than they did at age 50 or so, partly because of a reduction in 
muscle tissue, which is relatively dense and heavy.
    * The difference in weight tends to be more noticeable in men than in women, because men 
have relatively more muscle and less body fat.
    * Another reason older people weigh less is a loss of bone calcium, which makes bones more 
porous and fragile.
    * Please note that weight reduction is usually not good
    * Social connection depends primarily on the use of the senses, all of which become less sharp 
with each decade.

    * Although only 10 percent of the aged see well without corrective lenses, another 80 percent 
can see quite well with glasses and the remaining 10 percent have series vision problems.
    * Cataracts is a common eye disease among the elderly involving a thickening of the lens; it can 
cause distorted vision if left untreated.
    * Glaucoma is a disease of the eye that can destroy vision if left untreated. It involves hardening 
of the eyeball due to a fluid buildup within the eye.
    * Senile macular degeneration is deterioration of the retina that affects one in twenty-five people 
between the ages of 66 and 74 and one in six of those age 75 and older. This condition is hard to 
treat medically and is therefore the leading cause of legal blindness.

    * Presbycusis is the age-related hearing loss that affects about 40 percent of those aged 65 or older.
    * Most often presbycusis can be remedied with hearing aids.

     * Tinnitis - buzzing or rhythmic ringing in the ears experienced by 10 percent of the elderly. The 
only treatment at the moment is surgery, which is not always successful.      
   * The hard-of-hearing is likely to withdraw socially and to suspect that inaudible conversations 
are about them.
    * Elderspeak is a way of speaking to older adults that resembles baby talk, It uses simple short 
sentences, exaggerated emphasis, & repetition. Increasing logical pauses is a good thing to do! 
Lower pitch is better than higher, & it should be noted slower speech that stretches out the words 
actually reduces comprehension.
    * Sometimes younger adults automatically use elderspeak when they talk to older adults whom 
they do not know. Not good!

    * Adjusting to senescence - For optimal functioning, body changes require active adjustment, 
not passive acceptance. Adjustment involves finding the right balance between maintaining 
normal activities and modifying routines to fit diminished capacities. 

Secondary Aging

    * The distinction of primary & secondary aging is intended to emphasize the fact that aging and 
disease are not synonymous.
    * The specific physical illnesses or conditions that are more common in aging but are caused 
by health habits, genes, and other influences that vary from person to person is called secondary aging.
    * In one survey of 1,600 elderly people, the majority said their health does not limit their activities 
at all, even though 62 percent had two or more chronic conditions such as arthritis and heart disease.
    * Whether a particular elderly person is likely to be seriously ill, somewhat ailing, or in fine health 
depends primarily not on age but on genetics, past lifestyle, current eating, exercise habits, and 
psychological factors.
    * Nevertheless, it is undeniable that the incidence of chronic and acute diseases becomes 
greater with age.
    * Two Reasons for the increased incidence of chronic diseases follow:

1.) Older people are more likely to have accumulated several risk factors for chronic disease.

2.) Many of the biological changes that occur with aging reduce the efficiency of the body’s systems, 
making the older person more susceptible to disease.

# Older persons are more susceptible to disease, take longer to recover from illness, and are more 
likely to die of any disease or infection.
# A limiting of the time a person spends ill or infirm, accomplished by postponing illness or, once 
morbidity occurs, hastening death is called compression of morbidity. 

Causes of Senescence


    * Senescence – The state of physical decline, in which the body gradually becomes less strong 
and efficient with age
    * Wear & tear theory – a theory of aging that states that the human body wears out by time and 
exposure to the environmental stressors
    * Oxygen free radicals – atoms that have an unpaired electron due to metabolic processes
    * Antioxidants – compounds that nullify the effects of oxygen free radicals by forming a bond 
with their unattached oxygen electron
    * B cells – cells manufactured in the bone marrow that create antibodies for isolating and 
destroying invading bacteria and viruses
    * T cells – cells created in the thymus that produce substances that attack infected cells 
of the body
    * Average Life Expectancy – the average number of years a newborn of a particular population 
group is likely to live
    * Genetic clock – a theory of aging that states that a there is a regulatory mechanism in the DNA 
cells that regulates the aging process
    * Hayflick limit – The Hayflick limit is the number of times a human cell will divide before it stops due to the 
    telomere reaching a critical length. 

    * Wear & tear theory: humans, like machines, wear out with extended use.
    * The Wear & tear theory is refuted by research that finds activity promotes a longer 
and healthier life
    * If this theory were true it would be voided by the fact that present technology allows us to 
replace or mend many of our damaged parts

      Cellular Accidents

    * Most cells in the human body are completely replaced every few years
    * Some exceptions include select cells in the eyes, ears and brain which duplicate very 
slowly if at all
    * Cell mutations are caused by environmental chemicals, toxins, radiation, and occur in the 
normal processing of DNA repair.
    * When genetic instructions for creating new cells are imperfect, they don’t produce exact 
copies of the old cells

      Free Radicals

    * Free radicals are highly unstable because they have unpaired electrons and are capable of 
splitting or tearing apart molecules
    * The most damaging free radicals in humans are the oxygen free radicals which scrambles DNA 
molecules - This produces errors in cell maintenance and repair that can eventually cause cancer, 
diabetes, & arteriosclerosis.
     What can we do about it?
   * Research suggests that by consuming foods high in antioxidants (containing vitamin A, C, E, 
and the mineral selenium) we can significantly slow down this natural process
    * However, high doses of antioxidants in the pill form can actually cause opposite of the desired 
effect by increasing oxygen free radicals
    * Oxygen free radical production is inevitable in humans and is usually the side effect of normal 
body growth and maintenance, in reaction to infections and inflammation of the intestinal tract, and 
as a result of ultraviolet radiation
    * Point: the gradual accumulation of free-radical damage can be an attributing factor to the 
aging process
  The Immune System 
•  B cells & T cells are the two main types of (white blood) cells that the immune system uses to attack invaders. Their 
   function is to recognize foreign or abnormal substances in the circulatory system, isolate, then destroy them. 
•  B cells work by creating antibodies to destroy specific invading bacteria & viruses. 
•  T cells work by producing a substance that attacks any kind of infected cells. 
•  Natural killer cells (also known as NK cells, K cells, & killer cells) (2% of white blood cells) play a major role in the 
host-rejection of both tumors & virally infected cells. 

Immune System + Time

•  At about age 15 the thymus gland, (which produces the T cells), begins to shrink. 
•  By age 50, it’s only 15% as big as it was at puberty. 
Ψ  Do to B, T. & NK cell reduction , are diseases like cancer more common in the older adult?


•  People with stronger immune systems outlive their contemporaries. 
•  Females tend to have stronger immune systems because they have a larger thymus gland to start with. 
•  Downside to having a stronger immune system: more susceptible to autoimmune diseases such as 
   rheumatoid arthritis & lupus in which an overactive immune system attacks the person’s own body.
     The Genetics of Aging

    * Senescence accumulates in everyone at every point of the life span with variation as to the timing, 
duration, and type
    * One theory is that this is normal and result of a natural genetic plan apparent in everyone
    * Every living species has a genetically inherent maximum life span (~120 years in humans) that is 
not often exceeded

The Genetic Clock

    The genetic clock theory states that humans have a “genetic clock” in their brain that gradually 
“switches-off” the genes that promote growth and “switches on” the genes that promote aging.
    The genetic clock theory is strongly supported by laboratory research that showed that even cells 
grown in a controlled environment usually stop multiplying after about 50 divisions (the hayflick limit).

Can Aging Be Stopped?

    * Studies have been done in animals, such as monkeys, mice, chimpanzees, & fruit flies, that show 
there is a possibility for people to live longer.
    * These studies were done by reducing the animal species diet.
    * Most scientists believe that aging is associated with cellular level; however, not all scientists think 
that aging involves one gene. Many believe that aging is the result of “multiple cellular pathways” 
where there is no one factor acting out.
    * Most research that is done is not based on how to prevent aging; however, it is done on how to 
prevent disease, increase health, etc.
    * Getting enough nutrients is more problematic for the aged than for younger adults primarily 
because the senses of taste and smell diminish with age.
    * Poverty, living alone, and dental problems are external factors that make getting enough nutrients 
more difficult for some older adults.
    * Life expectancy in Sweden is high; where as life expectancy in Russia and Africa are low.
    * A centenarian is someone still alive after his or her 100th birthday.
    * Four characteristics of long-lived people follow:

         •  Diet is moderate.
          •  Work continues throughout life.
           •  Family & community are important.
            •  Exercise & relaxation are part of the daily routine.
# Calorie requirements decrease with age, where as vitamin and mineral intake increase with age.
# Drugs, alcohol, and dehydration also play an important role in nutrition for the elderly.
# The general public says they want to live longer; however, nobody wants to sacrifice anything to 
be able to do so.
# Exercise is needed more among the elderly but they do it less. Continuous rhythmic movements 
should be done for exercise not sudden, strenuous effort exercises.
# Fewer than 1 percent of people over the age 50 currently are on a diet or exercise.

Key Questions

1. How is ageism comparable to racism or sexism?

2. Why is the increasing number of people living past the age of 65 less a problem than some people 
imagine it to be?

3. What is the difference between primary aging and secondary aging?

4. What changes occur in the sense organs in old age, and how can they be ameliorated?

5. Explain each of the factors that affect how long a person is sick before she or he dies?

6. Evaluate the validity of the wear-and-tear explanation of senescence?

7. In what ways do the cellular theories of aging seem plausible?

8. What is the relationship between the immune system & aging?

9. How do genes contribute to the length of life?

10. Describe an epigenetic explanation for the aging process?

11. What conclusions can be drawn from Hayflick's research?

12. What are some of the characteristics of people who live to a very old age?

13. In your experience describe someone you know who looks younger or older than they actually are. 
Is this discrepancy a result of their health habits, their genes, or your own ageism?

                                             Growth & Development
                                                  Robert C. Gates