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July. 1965
Bulletin 710-1
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SA RBVIIw O
PrSIOLOGICAL AND PSYCHCHOGICAL CHANGES
IN AGING AND THEIR IMPLICATIONS
FOR TEACHERS OF ADULTS
(Reprint of 3rd Edition)
iffci.Vs onal, Technical, and Adult Education
StATR DEPARTMENT OF EDUCATION
D. Bailey, Superintendent
STallahassee, Florida
Wis. OrWNbA
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UNIVERSITY
OF FLORIDA
LIBRARIES
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ADULT EDUCATION
Bulletin 71G-1
July, 1965
A REVIEW OF
PHYSIOLOGICAL AND PSYCHOLOGICAL CHANGES IN AGING
AND THEIR IMPLICATIONS FOR TEACHERS OF ADULTS
(Reprint of 3rd Edition)
Prepared by
SAMUEL E. HAND
Division of Vocational, Technical, and Adult Education
Walter R. Williams, Jr., Director
Adult Education Section
James H. Fling, Acting State Supervisor
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A REVIEW OF
PHYSIOLOGICAL AND PSYCHOLOGICAL CHANGES IN AGING
AND THEIR IMPLICATIONS FOR TEACHERS OF ADULTS
Introductory Note
It has become increasingly clear that teachers in adult education, if
they are to be really effective, must be ever sensitive to the peculiar needs
and characteristics of adults as learners. In order to achieve and maintain
this sensitivity to the optimum degree, teachers must acquire a thorough
knowledge of the physiological and psychological changes that take place in
adulthood as a part of normal aging, and recognize the implications which
these changes hold for the teaching-learning process.
A review of the literature on aging reveals a wealth of information
and data regarding the physiological' changes that occur throughout the normal
life span. Considerable material is also found regarding the psychological
changes, including adult interests and adult learning, up through the age of
sixty. Beyond this point, however, there has been much less research, par-
ticularly with respect to intellectual changes and learning. It is significant
to note thatthe literature in this field is widely scattered through a great many
sources, and extensive investigation is required to pull together the various
facts which are significant to adult educators.
In the belief that such material would be helpful to the adult educators
of Florida, the writer has examined much of the literature on aging with the
thought of preparing a composite review of the significant physiological and
psychological changes that take place as a part of the normal aging process,
and of pointing out some of the implications which these changes hold for
teachers of adults. As the literature was examined, notes were made and
statements were recorded from various sources concerning these changes.
In addition, such other facts regarding adults and the aging process as
appeared significant and relevant to the purposes of the study were also re-
corded. The findings are summarized in the pages which follow.
PHYSIOLOGICAL CHANGES
Numerous studies having to do with the physiological changes in aging
have been based on the data collected by Sir Francis Galton in the year 1884.
A national health exhibition was being held that year at South Kensington,
England, and Galton set up a booth for the purpose of obtaining accurate
measurements of certain physical characteristics among individuals of various
age levels. At the conclusion of the exhibition, Galton had measured seven-
teen physical characteristics on more than 7,000 individuals ranging in age
from pre-adolescence through eighty years. His measurements included such
factors as stature, sitting height, span of arms, weight, strength of pull,
grip of stronger hand, swiftness of blow, vital capacity, visual acuity, audi-
tory acuity, and sense of perpendicularity.
Changes in Vision
Ruger (36) in his study of Sir Francis Galton's data, found that visual
acuity attained its maximum at about eighteen years of age and declined con-
tinuously thereafter. His curve of visual acuity plotted against age shows a
gradual and steady decline from about age eighteen to forty-two, a very sharp
decline from age forty-two to fifty-five, and a decrease in the rate of decline
beyond fifty-five. (See Figure 1. )
Jonas S. Friedenwald, in Cowdry's Problems of Aging (21), points out
there is a steady decrease in the average efficiency of all measurable visual
functions with advancing age, even in otherwise healthy eyes. The character-
istic senile or morphological and chemical changes of the occular tissues are
summarized as increased density, loss of water, increased interstitial fibril-
lar tissue, accumulation in some portions of the organ of an increased amount
of inert material, loss of fat and elasticity, together with isolated examples
of some rather bizarre forms of tissue atrophy. Friedenwald further points
out that aged eyes suffer a greater proportionate loss of visual acuity in dim
illumination; that the pupil is small and reacts feebly; that the cornea tends to
lose somewhat of its luster and transparency with advancing age, and that the
eyelids become thin, lacking in subcutaneous fat, and show a marked loss of
elasticity, particularly after the sixth decade.
Miles and Miles (37) state that visual function in terms of accommo-
dation range is a clear measure of physiologic age. They also point out that
visual acuity in its decline gives a basic index for psychophysiologic aging--
the well-known presbyopia measurement. In visual-perception and visual
memory tests on 600 persons ranging from the twenties to the fifties, Miles
found decrements in each successive age group.
MflALES
o 9
AG. IN Y*A A
FIGURE 1 AGE AND VISUAL AGUITY
(Reprinted by permission of the Galton Laboratory,
University College London, from "On the Growth Curves
of Certain Characters in Man (Males)," by Henry A.
Ruger, as published in Annals of Eugenics, Vol. II,
Parts Iand II, 19Z6.)
AcE IN YtAsts
FIGURE 1 AGE AND VISUAL ACUITY
Carlson (37) reports a gradual narrowing of the visual field, a slow-
ing down of the dark adaptation .(peripheral vision), and a gradually higher
threshold for light stimulation for man past the fourth decade. He also says
that the incidence of cataracts increases with age, irrespective of whether the
tendency to cataract formation is hereditary; that the gradual decrease of
elasticity of the lens is a vwell-known and accurately measured phenomenon of
aging; and that there is a diminished translucency of the cornea and vitreous
humor with age.
Janouskova, (16) reporting on examinations of 565 men and 446 women,
says that with rising age the rate of defective color vision rises, reaching
forty per cent in men in the eighth decade and eighteen per cent in women in
the seventh decade. Of the total rnen examined, 10.5 per c:'nit h;trd dr.ftc.tivf:
color vision; in women the percentage was 5.8. He found no relation between
defects in color vision and occupation.
Lorge and Kushner report studies by Henry C. Smith which show a
loss in color matching ability after age twenty-five. There was a feeling ex-
pressed, however, that this may be more a function of attitudinal factors than
of change in receptor physiology.
Breidenthal (3), in reporting on tests conducted by Ferree and Rand,
states that above age thirty-five there is a preference for more light for read-
ing than below thirty-five. This tendency is especially marked in persons be-
tween thirty-five and fifty, probably because the eyes are changing in their
refractive condition more rapidly than at any other period of the working life.
The change is so rapid that it is difficult to keep eyes continuously corrected.
Implications for Teachers
What implications do these research findings concerning visual
changes with aging have for teachers of adults? What influence should they
exert upon classroom teaching methods and procedures and on the selection
and use of audio-visual materials of instruction? Here are a few of the impli-
cations that are readily apparent:
For less acute vision:
1. Use good illumination. Older adults must have not only better
light, they must have MORE light. Do not have audience face the
light. Never have a flickering light.
2. Arrange seating so that people are close to the speaker and to the
materials used in class demonstrations.
3. Arrange and use equipment which will enable the audience to see
all parts of demonstrations easily and clearly. In addition:
a. Have a neutral background.
b. Use sharp contrasts of color
c. Use large charts, diagrams, and pictures.
d. Use large, legible writing or printing onlarge-sized blackboard.
e. Use simple words and phrases on the board. Avoid the use of
abbreviations.
f. Remove everything from the blackboard except those items
which pertain to the subject under discussion.
4. Shiny slate blackboards should be replaced wherever possible with
a newer type rough chalk board of such color that maximum con-
trast can be obtained with selected chalk.
5. Make sure that all duplicated materials for student use are done
with pica type and double spacing.
Changes in Hearing
Ruger's hearing curve, on which audio acuity is plotted against age,
utilizing Sir Francis Galton's data, shows that maximum auditory acuity is
attained between ten and fifteen years of age, very gradually but consistently
declines thereafter to about sixty-five, and then tends tolevel off. (See Figure .)
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FIGURE Z AGE AND HEARING
(Reprinted by permission from Annals of Eugenics.)
Lorge and Kushner (30) report the findings of the National Health
Survey studies on hearing ability (45) to show that clinically normal hearing
was reduced from incidence of 85 per cent among individuals five to fourteen
years of age, to about 12 per cent among those sixty-five and over. Conversely,
auditory disability sufficient to prevent understanding of speech originating at
a distance two or three feet directly in front, or to prevent using a telephone,
increased from an incidence of 7 per cent among five to fourteen year olds to
about 64 per cent among those sixty-five and over.
so lu ."
In the above study, using the pure-tone audiometer, it was demon-
strated that in the aging process women lose acuity for low pitches while men
lose acuity for high pitches.
Lorge also points out that many studies show that auditory reaction
time increases with age. In other words, we slow up in our reactions to
auditory stimuli as we grow older.
Carlson (37) says that from about twenty on, there is a gradual loss
of auditory acuity on all tones, but the loss of sensitivity is greater to the
high tones. The deterioration is greater in the male. He attributes the de-
cline in auditory acuity to a gradual but distinct atrophy of the nerve cells in
the basal coil of the cochlea. Local anemia, he points out, may also be a
factor.
W P. Covell, in Cowdry's Problems of Aging (21), states that the
central auditory processes become slowed down in old age, with the result that
cortical interpretation for speech and sounds lacks alertness and concentra-
tion. Many aged people find it difficult to follow rapid speech in spite of little
or no hearing loss. He feels that for the aged individual with marked hearing
loss, the psychological factors such as a feeling of insecurity, fear, and in-
ability to learn new things, readily serve to complicate the situation.
Implications for Teachers
The loss of auditory acuity with advancing age has definite and im-
portant implications for teachers of older adults. Some of these may be stated
as follows:
For less acute hearing:
1. Speak more slowly and distinctly as the age of the group advances.
2. Stand still, or relatively so,. so that those who depend to some ex-
tent, consciously or unconsciously, on lip reading will be aided in
understanding what is being said.
3. Unusual words, unfamiliar names, numbers, and the like should
be enunciated clearly and then printed on the blackboard.
4. Study the faces cf members of the group to see whether they are
hearing.
5. Use simple, well-chosen words that are clear and meaningful;
avoid the use of words that are lengthy and difficult to understand.
6. Use -the blackboard freely, particularly when there are some who
are not hearing clearly; vision will supplement hearing.
7. Talk directly to the group in a friendly, conversational manner;
use well-modulated voice; avoid monotone.
8. Be especially observant and eliminate inside or outside noises
that tend to interfere with the hearing of the group.
9. Questions directed to the teacher by members of the group should
be repeated for the benefit of the entire group before the questions
are answered,
10. Ask someone in the back of the room to call attention when any
member of the group cannot hear.
Miscellaneous Physical Changes
Sir Francis Galton's data (36) shows that various motor abilities such
as strength of pull, hand grip, et cetera, diminish slowly as age progresses
beyond twenty years. (See Figures 3, 4, and 5.)
MALES
AGE IN YT.AH1
FIGURE 3 AGE AND PULL
(Reprinted by permission from Annals of Eugenics.)
Carlson (37) lists certain age changes in the physiology of man and
other animals which appear at different age levels in the individual and at dif-
ferent age levels in the organ systems of the individual. He points out in pre-
senting these changes that we are here dealing with age changes primarily
inherent in the constitution of living matter, no matter how greatly these
changes may be speeded up by accidents of living. These changes are:
1. Gradual tissue desiccation.
2. Gradual retardation of cell division, capacity for cell growth, and
tissue repair.
3. Gradual retardation in the rate of tissue oxidation (lowering of the
basal metabolic rate).
4. Cellular atrophy, degeneration, increased cell pigmentation, and
fatty infiltration.
5. Gradual decrease in tissue elasticity, and degenerative changes in
the elastic connective tissue.
6. Decreased speed, strength, and endurance of skeletal neuromus-
cular reactions.
7. Decreased strength of the skeletal muscle.
8. Progressive degeneration and atrophy of the nervous system, im-
paired vision, hearing, attention, memory and mental endurance.
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FIGURE 4 AGE AND GRIP OF STRONGER HAND
(Reprinted by permission from Annals of Eugenics.)
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The following miscellaneous facts about the aging process are also
reported by Carlson:
1. The strength of the biceps at the sixth decade of life is only about
50 per cent of that at the age of twenty-five to thirty. The striated
skeletal muscle system shows fatty infiltration and brown atrophy
as age advances.
2. In persons past sixty, the capacity of the heart to increase in rate
and strength of beats during intense physical work is usually
diminished.
3. Instead of atrophy with age, the heart increases in size and
weight. But this does not mean increased efficiency.
4. The old saying that a person is as old as his arteries can still be
accepted as partly true. There is decreased elasticity of the
aorta, decreased elasticity and increased calcification in all ar-
teries in all people with advancing years--but not at the same rate
in all people.
5. It is now certain that the gonads are not a link in the life chain of
the individual; their absence does not shorten the life span.
6. Bones become fragile, less elastic, and more exposed to fracture
with age. Because of senescent changes in the bone, repair cannot
be normal. There is delayed union, and frequently, non-union.
Most authorities attribute the changes to arteriosclerosis- -that
is, impaired circulation and nutrition,
7. Skin changes with aging include:
a. Increased pigmentation of exposed parts
b. Decrease of water
c. Decrease of fat
d. Decrease of elasticity
e. Decrease in growth and regenerative capacity.
At sixty years of age, the same skin wound requires five times
longer to heal than it would in a child of ten.
8. Underweight as well as obesity tends to shorten life.
9. The kidneys show progressive reduction in weight after the fourth
decade. There is some evidence of actual decrease in quantity of
renal tissue as well as in some renal functions. The kidney, how-
ever, usually has sufficient reserve to meet the requirements of
age even to 100 or beyond.
10. There are indications of a heredity factor in falling hair, but diet,
disease, and vascularity unquestionably play a role.
11. It is well established that the incidence of pernicious anemia in-
creases with age, indicating in all probability an aging factor in
the gastric component or intrinsic factor in red cell formation..
12. The incidence of diabetes increases with age, at least up to fifty
or sixty. The pancreas of old people shows many scars from
accidents and injury of living.
On the average, physiological maturity is reached somewhere around
the thirteenth or fourteenth birthday (29). On the other hand, individual dif-
ferences are so great that some people are not physiologically mature at age
twenty. Women, generally, mature from twelve to thirteen years of age, and
men from thirteen to fourteen.
According to Shock (21) heat prostration is more frequent among the
aged than among the young. The death rate from heat strokes rises sharply
after the age of. sixty. In fact, says Shock, experimental studies reveal grad-
ually restricted powers of adjustment to both high and low external tempera-
tures as old age progresses. The body temperature with moderate conditions
is maintained within the usual range of diurnal variation. However, the
limits of adaptation tend to become gradually narrower as one passes through
the seventh decade to the later years of life.
Stieglitz (38) says that older people are less tolerant to starvation
and to overeating. He further states that in the aged where reaction to stress
is lessened, symptoms are less conspicuous. Symptoms of illness are not
due to injury; they are due to reactions of the body to the injury, and in later
life these reactions are less violent. Older people will often keep going about
their routine while suffering with conditions that would put younger people to
bed. This is sometimes dangerous because it tends to delay treatment,.
Other physical changes that occur in normal aging, according to
Stieglitz, include the following:
1. Repair after injury is slowed with age. Convalescence time in-
creases up to twelve times that required for youth.
2. Lessened reserves for stresses and reduced tolerances for heat,
cold, overeating, dehydration, and salt depletion are noted.
11
Miles and Miles (37) found that in complex manual activities, speed
and dexterity losses appear as age advances. The rate of decline was gradual
from age twenty to sixty, but increased sharply thereafter. Previous exper-
ience or practice was found to retard the age influence.
-On tests of capacity for physical work, Miles found decline with age.
At seventy-one years, the capacity for physical work was found to be about
50 per cent of what it had been at age forty-one. The work-score was about
3. 5 per cent higher in the afternoon as compared with morning at ages fifty-
seven to sixty-eight.
Dawson and Hellebrandt (6) also found that working capacity fell off
with age, and that afternoon scores were better than morning scores.
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FIGURE 5 AGE AND VITAL CAPACITY
(Reprinted by permission from Annals of Eugenics.)
Lehman (24) reports evidence to show that the tendency to attribute
to the age factor things that have little or nothing to do with age per se should
be reoriented. He presents 115 biological excerpts in which he cites examples
of outstanding creative achievements completed not earlier than the late
sixties.
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Lorge and Kushner (30) cite certain studies made at the Harvard
Fatigue Laboratory which also indicate that the quality of work does not de-
cline very rapidly after age forty-five. They point out also that there is con-
siderable evidence otherwise to show that the age at which eminent people do
their best work does not coincide with physiological prime. For example, out
of the 100 most important inventions, 37 were made by men over forty and 16
were made by men over fifty.
The general physiological changes in aging imply that the hixman
organism consciously or unconsciously alters its mode of life to adjust to
these changes. Lorge feels that perhaps one of the more subtle adaptations
to physiological change is the choice of work tempo.
Implications for Teachers
For the slowing up in physical tempo and the narrowing limits of
homeostatic adjustment the following implications seem to appear:
1. Older adults must be permitted to choose their own work tempo.
They should be encouraged and stimulated, but not rushed.
2. Be particularly attentive to the physical comfort of older adults;
maintain classroom heat and ventilation within proper limits;
arrange for use of the most suitable furniture available.
3. Arrange for an accessible meeting place--one which requires a
minimum of stair climbing.
4. Arrange the schedule of meetings insofar as possible to best suit
the group.
5. Maintain a pleasant social atmosphere in the classroom.
6. Do not hold meetings overtime.
7. At the appropriate time, emphasize the importance of individual
responsibility, with respect to avoidance of environmental ex-
tremes and conditions of stress on the part of older adults.
PSYCHOLOGICAL CHANGES
Changes in Intelligence and Learning
The literature shows that psychologists differ rather widely as to the
effects of age upon intellectual capacity or the power of the individual to learn.
It shows also that there exists among the older people, as well as the general
population, long-accepted stereotypes of the aging which tend to picture the
older person as one whose physical and mental capacities are deteriorating
and whose general interest in life is gradually diminishing. Research up to
this time has not been sufficiently extensive or intensive to give unequivocal
evidence of the influence of age upon intellectual capacity (42).
Thorndike (41) some twenty-five to thirty years ago did considerable
research on the question and his conclusions were as follows:
1. The acme of ability (to learn) is reached at some point between
twenty and twenty-five years of age. (See Figure 6.)
2. There is a decline in capacity for learning from the acme (twenty
to twenty-five years) to about forty-two years of age of from
13 to 15 per cent, or approximately one per cent per year.
3. The influence of intellect upon the curve of ability to learn in re-
lation to age is very slight. The ablest man and the ordinary man
show very nearly the same curve.
4. Individuals on the average probably learn much less from twenty-
five to forty-five than they did from five to twenty-five. This is
attributable to various combinations of four factors: general
health and energy, ability to learn, interest in learning, and
opportunity for learning,
5. By the age of twenty-five most persons have, within certain limi-
tations, learned a great part of what they wish to learn.
Following World War I, Jones and Conrad (17) administered the Army
Alpha Tests to 1, 191 unselected rural New England subjects from ten to sixty
years of age and when the results were plotted against chronological age it
showed rapid intellectual growth to about sixteen years, a negative accelera-
tion to about eighteen or twenty years, and a gradual but steady decline there-
after. The performance at the fifty-five year level was about the same as
that of the fourteen year old. The subtests on vocabulary and general infor -
mation failed to exhibit a post-adolescent decline, as did the other tests. The
most rapid decline was found to be on analogies, common sense, and numeri-
cal completions. Jones and Conrad concluded that the tests on vocabulary
and general information were the least valid indications of intelligence, and
considered their findings as confirming Thorndike's conclusions--that intel-
ligence declines steadily beyond the age range twenty to twenty-five years.
They also concluded that speed was an unimportant factor in the measure-
ment of intelligence.
S
AGE
30 40
50 Years
FIGURE 6 -
THE GENERAL FORM OF THORNDIKE'S CURVE OF ABILITY
TO LEARN IN RELATION TO AGE
(From: Thorndike, E. L., Adult Learning, New
York: Macmillan Company, 1928, p. 127.
Reproduced by permission. )
Weschsler and Shakow(46) conclude on the basis
of intellectual and physical ability that: (a) intellectual
follows the same general pattern decline as does physical
individual abilities (vocabulary, memory, et cetera) which
intelligence must of necessity partake of this decline, but
the same rate.
of various studies
ability as a whole
ability, and (b) the
enter into general
not necessarily at
Litwinski (25) concludes that while perception declines in old age,
other factors such as imagination and intuition seek to replace the failing
powers.
Lawton (23) says that clinical evidence convinces him that if the
speed factor is eliminated and only mental power is considered, the difference
between older and younger people is reduced.
Foulds and Raven (9) administered the 1938 Progressive Matrices
and the Mill Hill Vocabulary Scale to 1, 047 engineers and 920 male employees
of an industrial firm--one competitive and one non-competitive in situation.
The rate of decline in the Matrices Test was uniform from age twenty-five
on; the vocabular scores showed a constant rise to about thirty, with little
decline to age sixty. On the basis of this they concluded:
1. The average person's ability to form comparisons and reason by
analogy increases rapidly during childhood, reaches its maximum
I_ __ __
at about age fourteen, remains constant to about age twenty-five,
and then declines steadily to age sixty and then more so to eighty,
at which age the average person can reason by analogy about as
well as an eight year old.
2. The ability to recall information increases normally up to age
twenty-five and remains constant for twenty-five to thirty years.
Miles and Miles (37) cite the results of intelligence tests by many
investigators as giving what they consider to be clear-cut evidence of the
following:
1. Score decline from young adulthood to old age.
2. Greater decrement of "speed" versus "power" of intelligence.
3. Better preservation with age of the verbal as compared with the
mathematical and manual functions.
4. Wide individual differences in score at every age.
In connection with age-score curves on intelligence tests, Miles
makes the following observations:
1. If speed of reaction or youthful vigor is essentially involved in the
test performance, decrement begins to appear early in adulthood,
is continuous, and tends, in later age, to become excessive.
2. On the untimed or "power" tests of intelligence, score decrement
occurs with age, but the rate of decline is slower.
3. The average decade scores of men and women are generally about
equal whatever test is used, and they describe about the same
decrement curve.
4. At every adult age the best and the poorest scoring 25 per cent
differ from the average by an amount that is more than three
times the usual decade to decade loss.
With respect to learning, Miles points out that learning ability is
closely correlated with intelligence. He says that training utilizes capacities
and practice maintains them. Measured ability to learn is maintained
slightly better than the capacity to do mixed problems of the intelligence test
type. If learning were required of all people in all subjects, the decline of
competence with age might be similar to that of intelligence test capacity.
Since learning is selective, however, and generally follows interest, the
waning of capacity is retarded by the favorable factors which motivate the
choice of material to be learned.
Learning obviously depends upon attention, retention, and recall,
says Miles. That these separate elements show greater decline with age than
does learning itself simply means that in the latter other factors are also
involved. Wanting to learn is the greatest aid to learning. Interest in the
subject to be learned aids in the mental organization necessary for attention
and retention. Attitude, interest, and motivation are better sustained as age
advances than is the speed of activity, and they tend to channelize and conserve
effort in the direction of organized patterns of experience. In childhood,
active, varied learning is the rule; in maturity, active learning is usually
practiced in areas defined in terms of interest.
There is no veco power over learning exercised by age at any period
in the normal life span, according to Miles. While experimental psychologic
results are in agreement in indicating age decrements in adult learning, at
the same time they definitely support the formulation that no one is ever too
old to learn.
Donahue (43) makes the following observations with respect to
intelligence and learning in the aging:
1. The general age curves for psychological functions are parabolic
in shape.
2. The same abilities decline at different rates in different persons.
3. Judgment and reasoning ability reach their peak latest of all
abilities.
4. Age differences and age changes have frequently been confused.
5. There is good evidence to support the view that the greater the
individual's intellectual endowment and the greater the amount of
education, the less steep is the decline in intellectual ability,
other things being equal.
6. Exercise of the mind seems to retard deterioration of intellectual
processes.
7. If minds are kept active through exercise of intellectual and
creative imagination, outstanding achievements in fields not in-
volving physical powers is possible in the seventh and perhaps
even the eighth decade.
8. The older adult can continue to learn meaningful things; compre-
hension of difficult reading shows little or no change with age; but
there is a decline in ability to remember isolated facts.
9. The speed of perception steadily decreases from decade to decade.
If not too marked, defects of sense and perception can be compen-
sated for by experience and persistence in practical situations.
Lorge (26, 27, 28, 29, and 30) differs from the majority of other
psychologists in his conclusions regarding the effects of age upon intellectual
capacity. Observing that the conclusions of others regarding intellectual
decline vere based usually on tests which depend for performance on both
speed and power, he set out to measure the two factors separately. Lorge
felt that the older people were being penalized in "speed and power" tests by
virtue of the inevitable physiological changes which take place with aging and
serve to slow them down, but which, in his opinion did not necessarily re-
duce their capacity (or power) to learn.
To test this proposition Lorge administered four kinds of tests to a
large number of WPA workers of different ages. First, he gave these people
the IER Intelligence Scale C.A. V. D. a test of intellectual power with unlim-
ited time allowance. He then selected a number of those at various age
ranges who had made the same scores on the C.A.V.D. power test and gave
them three timed tests of "speed and power, utilizing the Otis Self-
Administering Test of Mental Ability (20 minutes), the Army Alpha, and the
Thorndike Intelligence Examination for High School Graduates. The following
are the results:
Unlimiteores
Age Time Limited Time
S_ Army Alpha Otis Thorndike
1 20-.25 405. 3 149 6 44.4 66. 9
2 271/2-371/2 405 7 142. 3 39. 3 60. 3
3 40 and over 405. 5 128. 7 33. 4 53. 0
From the above Lorge observed that the tests allowing a limited
amount of time show a steady decliiu with age while the test which allowed
unlimited time showed virtually no change from one age group to the other.
He concluded, therefore, that there is a decline in rate of learning as age
progresses, but that intellectual power in and of itself does not change from
about twenty to beyond sixty. (See Figure 7.) He attributes the decline in
rate of learning to the losses in visual acuity, auditory acuity and reaction
time, primarily. The increased fear of failure and general attitude of
reluctance toward learning on the part of older adults were also mentioned
as possible factors in the decline.
Lorge goes on to show that if the correction for loss of 780 point
per year of age beyond twenty due to speed, as revealed in his data for the
Army Alpha, is applied to Jones and Conrad's data, the results would then be
consistent for all age groups in their study.
-- -7-'~ -~-- Lorge
0 Thorndike
0 10 20 30 0 50
FIGURE 7 CONTRAST OF LORGE'S AND THORNDIKE'S
GENERAL CURVE OF ABILITY TO LEARN IN RELATION TO AGE
Changes in Interests and Attitudes
Strong (39) made an extensive study of the change of interests with
age among adults. He found that some interests increase and some decrease
with age. In some cases the changes are very slight, in others they are
great, but there is no reason, he says, to assume that interests alter cap-
riciously, inexplicably. Each interest waxes or wanes in a definite way.
Analyzing vocational interest blanks filled out by 2, 340 men between
the ages of twenty and sixty, representing eight professions, Strong arrived
at the following conclusions:
1. Older men are no more catholic in their interests than younger
men; they have as many likes and dislikes as younger men but
their likes and dislikes are not identified with those of younger
men.
2. Change in interest does not take place uniformly from twenty-five
to fifty-five. In round numbers, 50 per cent of the total change
occurs between twenty-five and thirty-five, 20 per cent between
thirty-five and forty-five, and 30 per cent between forty-five
and fifty-five. There is little or no change from fifty-five to
sixty-five.
3. Changes in interest from decade to decade are not great. Differ-
ences as represented by occupational interests are much greater
than differences due to age.
4. Items suggesting physical skill and daring (such as walking along
a precipice, or being an aviator) show the greatest change of all.
Older men do not like such activities as do younger men.
5. The next greatest change is registered by items suggesting change
or interference with established habits or customs.
6. With few exceptions, liking for occupations decreases with age.
7. Linguistic activities of an oral or written nature decline in inter-
est, but those involving reading increase in liking with age.
8. Many amusements are liked by large percentages at all ages.
There is a distinct tendency, however, for all of them to decline
except those that may be characterized as cultural. These in-
crease in liking. Older men also prefer, more than younger men
do, those amusements pursued alone in contrast to ones involving
others.
9. Liking for people exhibiting desirable traits increases with age,
as does disliking for people exhibiting undesirable traits. Evi-
dently men are more unanimous in their likes and dislikes toward
kinds of people than toward any other group of items.
10. Older men are somewhat surer of their estimates of themselves
than are younger men.
11. In general, the things we like most at twenty-five years of age
are liked better and better with increasing age, and the things we
like least at twenty-five are liked less and less.
Strong makes the observation that every interest, seemingly, is
based to some extent on innate qualities, largely of an emotional nature. But
interests are also expressions of experience and learning. Thus, interest
in cabinet-making can only continue if the workman's skill is sufficient to
enable him to turn out work that merits approval from his associates and
from himself.
Thorndike (40) offers the following conclusions, based on his research
on adult interests:
1. There is a slight decrease in the total volume of interest from the
twenties to the fifties. The decrease is restricted largely to the
physical activities.
2. The interests needed to support adult learning show no decrease.
In them there is no steady, unavoidable decline or "drying up. "
3. Interests can be modified. Likes and dislikes can be learned by
adults as truly as names or dates,
4. The general principles of modifiability and control of interests
are the same for all features of human nature. Interests and
everything else are strengthened by causing them to occur, and by
rewarding them.
5. Learning without interest of some sort does not occur to any
appreciable degree. Results of experiments present these facts:
first, lack of interest is a handicap; secondly, the handicap is
small. Adults can learn wrong meanings of words, wrong birth
dates of celebrities, and false biographies (all of no intrinsic
value or interest whatsoever) nearly as well as true and useful
facts.
6. Whatever difference exists between young adults and old adults as
to willingness to learn, interest, ability to apply their minds, et
cetera, are moderate in amount, and will not prevent the older
group doing at forty-five on a somewhat reduced scale almost
anything they could have done at twenty-five.
7. On the whole, the older adult is more influenced than the young
adult by uselessness and harmfulness of the material to be
learned. We may estimate roughly that 10 to 20 per cent more
time would be needed for the old adult than for the young adult to
counterbalance the change from fairly useful content to utterly
useless or harmful content.
8. The old suffer greater dimunition in the amount learned under
conditions of mild bodily discomfort than do the young.
9. The old suffer more than the young from being frustrated by de-
privation of success, but not much more.
Miles (37) says that even at eighty, the attitudes and interests of
men and women, although nearer together than at any other time since early
childhood, are yet significantly diverse. The changes with age appear to
follow the pattern of:
1. Waning of active in favor of passive pursuits;
2. Waning of social in favor of individual recreations;
3. Waning of variety in favor of narrowing selection;
4.. Waning of changing environments in favor of a comfortable,
settled routine.
In a study of attitudes and adjustments of 396 recipients of old age
assistance in New York State, Morgan (32) reached the following conclusions:
1. Men had better health than women, and a close correlation exists
between health and happiness.
2. Forty per cent of the happiest people had more than an elementary
education, while only 24 per cent of the unhappiest ones had more
than elementary schooling.
3. Seventy per cent of them said they would be much happier if they
had a job.
4. Forty-four per cent rated themselves as physically capable of
holding a job.
5. Work and social responsibilities were the sources of greatest
happiness.
6. Women find it easier to occupy themselves. Thirty per cent more
women than men reported they had plenty to keep them busy.
7. Most of them considered young adulthood (twenty-five to forty-five
years of age) to have been the happiest period of their lives.
8. Finances, concern for spouse, and poor health were, in that
order, reported as sources of greatest worry.
9. There are no aged characteristics as such; traits exhibited by the
old are as varied as those shown by a group of young people, and
are determined by the same factors--cultural, educational, econ-
omic,and sex differences.
Cavan (5) says that the attitudinal and emotional changes that occur
in old age are characterized by:
22
1. Worry, especially over health and economic security;
2. A sense of inadequacy, leading to feelings of insecurity, anxiety,
or guilt;
3. Feelings of being unwanted, isolated, and lonely;
4. Attitudes of suspicion;
5. Narrowing of interests, leading to introspection and increased
interest in bodily sensations and physical pleasure;
6. Loss of interest in activity and increased interest in quiescence;
7. Reduction of sexual activity but sometimes increased sexual
interest, especially in the male; regression to earlier levels of
sex expression;
8. Conservatism;
9. Inability to adjust to changed conditions;
10. Over-talkativeness, especially of the past;
11. Hoarding, often of trivial things;
12. Tendency to relive past events.
Miscellaneous Psychological Changes
The following are miscellaneous facts and conclusions regarding the
psychological aspects of aging, reported by various writers:
1. The most critical years in the aging process occur between the
fortieth and sixtieth years. It is in this period that most can be
accomplished in preparation for successful old age (14).
2. Frequently the fear of aging, rather than the aging process itself,
induces mental deterioration. This is the result of social pres-
sures in our society and calls for a better understanding of the
place of the aged in the picture of the full life span (14).
3. A study of over 700 people whose mean age was 85.5 years and
who lay at the two extremes of wealth and poverty revealed the
following formula for longevity:
An increase of life duration is favored by marriage, descent
from healthy, long-lived parents and grandparents, breast
feeding, moderation and regularity in the conduct of life, cheer-
fulness and occupation till a ripe old age, and retardment of
retirement (14).
4. -It must be emphasized that (in aging) all changes are not necessar-
ily in the direction of decline. For example, although muscular
strength, vigor, and speed of reaction decline with advancing
years, skills tend to increase with long practice. Though there
may be less intense emotional drive or ambition, there occurs an
increasing loyalty and calmness, with clearer definition of purpose
of living, upon further maturation. These compensate for the
restless drive of ambition in youth (14).
5. Careful studies on learning have revealed that the maximum speed
and rate of learning occurs at age twenty-two. At age eighty the
rate of learning is practically the same as at twelve. However,
there are qualitative as well as quantitative differences in ability
to learn. Though speed is lost, accuracy is increased (4).
6. A definite non-chance relationship was found to exist between
participation in constructional activities in childhood (six to
eighteen) and participation in constructional activities either as
hobbies or favorite leisure activities in adult life. The desire or
lack of desire to participate in such activities in adulthood depends
largely upon whether one has or has not done so in childhood (33).
7. Adults are proverbially less ready to adopt new ways, or even to
try new ways, than adolescents (41).
8. It is generally recognized that certain mental changes may be
looked for as accompaniments of normal senium. In general, the
first thing noticed is a slight decrease in alertness, a tendency to
slow up, and a narrowing of the span of interest. Accompanying
this, and at the start rather insidious, is the loss of memory,
particularly in the field of spontaneous recall. The patient be-
comes somewhat absent-minded, he forgets where he has put
things, cannot remember names, and perhaps later on, forgets
faces. This impairment of memory is most striking for recent
events, the events in one's earlier life standing out in bold relief,
often being described with considerable prolixity (37; Overholser).
9. We know that work is a good means for the retardation of senility
(11).
10. Older workers are:
a. Steadier in their jobs, require less frequent replacement, and
are less expensive in training;
b. More careful with equipment, less wasteful of materials, and
have fewer industrial accidents in relation to hours worked;
c. Less distracted by social interests and tend to develop a strong
sense of loyalty and responsibility;
d. Sick more often, and require longer to recover from illness
or accident, but they show greater caution and have a lower
accident rate (37; Miles and Miles).
11. The expressed interests in leisure pursuits of 1, 500 cases were
examined, and those interests actively pursued were tabulated by
Reeves and Slater. The most popular interests were found to be
non-competitive sports, constructional activities, and reading.
The span of interest did not change appreciably with age, although
the direction of interests increased, with a greater variety of
interests found at older ages. Intelligence was found to be
associated with span of interest, and the more intelligent had the
more mature interests (35).
Implications for Teachers
Implications for teachers of adults as indicated by these research
findings on the psychological changes with aging seem to fall into three
categories: First, the general tone of the research shows that there is a sub-
stantial retention of the POWER to learn, but a slowing up in the RATE of
learning as we grow older. The implications for teachers in this and related
facts developed in the research would seem to include the following:
1. Expect quality--but remember that it will take longer to produce
it.
2. The scope of lessons must be planned with due regard for speed
capabilities of members of the group.
3. Present new material in the most logical sequence, step by step,
and relate it to what is already known. Short units of work will
tend to give adults a feeling of success and mastery, and this is
highly important.
4. Utilize various instructional aids to help establish important
concepts and relationships. Write things on the blackboard as
they are explained. Double exposure (sight and hearing) will help
solidify learning.
5. To help compensate for slower correlation of ideas, select the
central idea or principle, then plan class demonstrations, explana-
tions, and discussion so as to develop and reinforce the basic,
central idea.
6. Repeat important points frequently.
7. Summarize often--remember the difficulty of older adults on
spontaneous recall.
8. Because of the widespread existence of negative attitudes regard-
ing the ability of older adults to learn, the teacher must make a
special effort to reassure adults on this point; he must overcome
their feelings of insecurity and fear of competition with younger
adults and give them a new sense of security and mastery.
9. In laying out tasks to be performed in the learning process, the
teacher must make sure that the adult sees the relationship of the
tasks at hand to his ultimate objective.
10. Since learning flows primarily from the consequences of satis-
faction and reward, every opportunity should be utilized with
adults to praise good work. By the same token, errors should be
minimized and all kinds of punishment (including sarcasm and
ridicule) avoided. Accent the positive (success), not the negative
(failure).
11. Do not forget the importance of short recesses (or breaks) for
adults.
12. The adult comes to school with a purpose. Often the urgency and
seriousness of his purpose results in a drive for achievement
which becomes a source of discouragement. He may expect more
rapid achievement than he is capable of producing. The teacher
must be keenly observant for signs and symptoms of this difficulty,
because if not detected and proper counsel and encouragement
given, the individual will drop out with a feeling of disappointment
and frustration.
Secondly, the wide range of. individual differences in age, ability,
previous education, and interests of adults would seem to hold the following
implications for teachers:
1. Remember that every member of the group is a voluntary partici-
pant. As such, each one is there because he wants something.
One-of the most difficult and important jobs the teacher faces is
that of finding out what each person's particular interest or need
is. Unless the adult gets what he is coming for, he will soon stop
coming.
2. Every group of adults has a wide assortment of talents, and these
constitute rich resources for the group. To identify these
resources, there should be an early effort made in every group to
get acquainted all around. The teacher has a particularly im-
portant responsibility here in studying the background, interests,
needs, and capabilities of each member of the group, so as to
plan the work for the group and utilize to the optimum degree the
talents of each member for the benefit of the group as a whole.
3. In the classification of adults for placement, and in dividing a
class because of size, do so on the basis of previous education
rather than age.
4. Do not give adults "busy-work" to do. Engage them in challenging,
meaningful activity, according to their particular interest.
5. Make everyone feel that his opinions, needs, and thoughts are
important.
6. Encourage everyone to share in group activities. This will give
older adults the feeling of belonging oftentimes needed to allay
their fears about returning to school.
7. Remember that the adult brings with him much of the vocabulary
and stored knowledge which will facilitate and give depth to new
learning.
8. In learning new skills, adults often have to unsett" old patterns,
long established. This may be almost frustrating in extreme
cases. It is time consuming in all cases. Teachers can soften
the effect of this experience for the older learner by explaining
that this is a common problem, not at all peculiar to him.
Finally, the sum total of all the changes that constitute the aging
process seems to be an appalling lack of proper adjustment on the part of a
large percentage of our aged population. In this fact seems to lie one of the
most significant implications of all. Not only teachers, but all educators, and
particularly adult educators, must become concerned with the job of finding
ways and means of helping adults reach old age in a more satisfactory state
of adjustment. Steps must be taken to get across to adults the kinds of infor-
mation they need about the aging process to help them formulate a wholesome
philosophy about growing old. Ways must be found to train adults in the
techniques of attaining high levels of personal adjustment. We must also
provide training and retraining in the skills and knowledge which will make it
possible for them to continue in employment and socially satisfying activities.
And finally, we have a responsibility in the much needed job of convincing
our respective communities all over the land that people can learn throughout
life, and that our older people deserve and must be given the opportunity of
continuing to use their skills and productive capacities and to participate in
the social life of our communities.
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