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Old dogs, new tricks: a look at learning and memory in the older adult
Geoff Easting, University of Surrey
All animals grow old. However, what makes the human animal unique is that it is the only one possessing awareness of its own ageing. We all know that we are different now from when we were schoolchildren and that sometime in the future we will be different from what we are now. Awareness, unfortunately, does not necessarily bring with it understanding and ageing is a phenomenon that tends to be shrouded in myths.
There is, for example, the fairly widely held opinion that as one grows older both interest in and capacity for sexual behaviour declines to a point where it becomes almost non-existent. The work of Masters and Johnson1 has demolished this particular myth. They found that elderly people, provided that they are healthy, are perfectly capable of indulging in sexual activity and, indeed, of experiencing orgasms well beyond the age of 80.
Other myths abound, the idea that most old people are constantly ill, they actually get fewer acute illnesses than young people. It is true that 81% of people over 65 as opposed to only 54% below that age have some chronic problem but this need be nothing worse than short sight or hay fever.
The notion that older people become set in their ways and more conservative is also widespread. There is some evidence that older people tend to become more stable in their attitudes, but it is clear that most older people do change and adapt to the many major events that occur in old age such as retirement, children leaving, bereavement, changing location and so on. Their political and social attitudes also tend to shift with those of the rest of society, although at a somewhat slower rate than for younger people2. An example of this is the attitude towards legal abortion.3
Allied to this last notion of conservatism is the widespread belief that people tend to become more religious as they grow older. Yet another myth. Older people do not tend to become more religious as they age. It is true that our present generation of older people tends, in general, to be more religious than younger generations. But this appears to be a generational difference rather than an ageing one. We must remember their upbringing, they have been more religious all their lives rather than becoming more religious as they aged. Longitudinal studies such as those undertaken by Blazer and Palmore4have found no increase in religious interest or activity as people grow older.
We could go on and look at a number of other myths about ageing. Good sources are Palmore and Comfort5. What it amounts to in sum, is that all of these widely held views reinforce the negative stereotype of old people. In other words, an overall unfavourable impression of an entire group of people. This is now commonly referred to as ageism6. The notion of ageism is that people become a distinct and inferior sub-section of society simply by living longer than the majority of that society. It is depressing to note that it is not only young adults who subscribe to this notion - the elderly themselves are also guilty.7
A number of studies demonstrate the operation of this stereotype in the evaluations which young adults make of elderly people in general.8 But what is potentially more worrying is the fact that medical students often express negative attitudes towards treatment of elderly patients and geriatric medicine is regarded as the Cinderella of the medical profession.
This negative stereotype of old age, in which elderly people are seen and evaluated in terms of the stereotype rather than in terms of their actual competencies and skills, is probably acquired from a steady diet of the exaggerated negative picture of elderly people found in folklore, literature and television. In folklore adages abound 'you can't teach an old dog new tricks'; 'there's no fool like an old fool' and more recent derogatory terms such as 'old fogey' and 'dirty old man'. Television, in the words of Kausler9, has been especially unimpressive with its negative portrayal of the elderly. In commercials, elderly performers are commonly seen as members of the pathetic laxative generation, rarely as members of the fun-loving 'Pepsi generation'.
There is a brighter side to this somewhat gloomy picture however. During the last decade there has been a veritable surge of interest by psychologists in the area of changes in behaviour during adulthood. An interest in getting beyond the myths and the stereotypes and looking at what really occurs as people grow older. Their efforts have thrown up a great deal of evidence about age changes in cognitive activities such as learning, memory, concept formation and problem solving. What they have discovered is that proficiency for many tasks employed in experimental psychology does decrease over the life-span. The decline in some instances is of little practical significance, in other instances the decline can have greater practical significance. What is clear is that if as educators we wish to instigate appropriate compensatory actions involving elderly people, an adequate knowledge of these deficits is essential. The object of this paper is to review some of the research on cognitive processes in adults in order to understand what might be done.
Of the myths already referred to, one of the most persistent is that embodied in the title of this paper - the idea that old dogs are not capable of learning. At one level it is of course a nonsense. Imagine for a moment that this was really true, and that at some arbitrary age - 60, 65 or whatever, all learning suddenly ceased. What would happen to that person? They would, of course, have their existing knowledge so they would still be able to read, write, drive the car, play scrabble and so on. But what about new information about local, national and international events? The names of the new mayor, the new prime minister or new leader of a foreign country would be perceived but not remembered so that they would be unfamiliar each time they were encountered. Knowledge would not be the only aspect to suffer, new skills could not be learned, learning to adjust the new cordless television set, learning a new card game to play with the grandchildren. Retiring and moving to the seaside would be absolute chaos. Which room in the house is which? Where are the local shops? Is that person a neighbour or a stranger? The fact that older people have very little difficulty with any of these things illustrates that learning is going on continuously throughout life and that elderly people remain highly active learners.
This example of some of the activities which would be curtailed in a life without learning, highlights one of the difficulties of attempting to review the research in this field. That is, the enormous diversity of learning activities. The Annual Review of Psychology covers the topic of 'learning and memory' each year and each review normally cites up to two hundred current references. For references applied specifically to learning in the adult years two very good recent books are Birren & Schaie and Kausler10. One should also mention the SCUTREA initiated project by our colleague Paula Allman11.
It is impossible in a paper this length to review all the experimental ageing studies on learning but an attempt will be made to synthesise some of the knowledge gained about learning ability as a function of ageing. We will concentrate on two main areas. First of all, reaction time or speed of response, and secondly, the broad area of cognitive functioning.
It is obvious to everyone that as people grow older they slow down. A man in his sixties is still capable of running a mile, or even a marathon, but not as fast as in his twenties. This slowing down is not only physical it also affects cognitive functioning, that is, there is a slowing of transmission within the nervous system. There is, as yet, no certain answer as to why this slowing should occur. One possibility, proposed by Salthouse12 attributes it to an increase in neural noise. The assumption being that the diminished functioning of older brain cells results in a decreased signal-to-noise ratio as well as the slower transmission of neural messages. Salthouse in fact argues for a universal decrement principle in which this slowing down is the mechanism responsible for virtually all age differences in behaviour. The decrement principle certainly finds lots of experimental support13. It also ties in neatly with the classical associationism approach to ageing deficits. That is, learning deficits occur because older people are slower than younger people in rate of rehearsal. However, questions remain about how universal the slowing down is in old age. To be truly universal there should be no exceptions - every type of behaviour should be affected by the slowing down. This though, is not the case. Waugh14 found no age differences in the rate of reading words and Nebes15 found a slower reaction time for elderly subjects only when the required response was a manual one (depressing a key) not when it was a vocal one.
Typically, learning ability has been measured under time limits, the subject producing the greatest number of correct responses in a specified time is assumed to have the greatest learning capacity. In this kind of measure younger people normally come out on top. However, there is very little evidence that speed of learning is important in adult learning. In fact there is some evidence16 that it is overemphasised to the detriment of learners or all ages. In general it is true to say that older learners perceive more slowly, think more slowly and act more slowly than younger people do. There are, however, substantial individual differences, and reaction time itself should not necessarily be a handicap to an older person wishing to learn something. Knox17 says 'When a wide range of learning abilities is included, the general conclusion is that most adults in their forties and fifties have about the same ability to learn as they had in their twenties and thirties when they can control the pace'. If the tasks are fast paced, unusual and complex, however, there is a noticeable decline in learning ability with age. It is obvious then, that educators dealing with older people must avoid situations that entail time pressures and potential surprises. One way to offset the latter is by the use of advance organisers18. These are information introduced before the learning material which give the learner some perspective of the more detailed material to come and provides the 'intellectual scaffolding' on which he hangs like new details.19
When we turn to our other area, that of cognitive abilities, we immediately become involved with some of the controversial issues involved in this psychologically sensitive area. On the one hand, we have the environmentalist viewpoint which contends that insofar as intelligence is a product of learning, it should increase throughout life, in other words, intelligence should improve with learning and experience. If tests do not show this, it is argued, then something is wrong with the tests. On the other hand, we have the biological approach which compares intelligence to growth in stature. It should grow up to the late teens, then remain stable for some years and eventually decline. These two positions are broad reflections of the well-known nature/nurture controversy which has tended to dominate the literature on intelligence over the years.
As everyone who has ever done a teacher education course knows, the first intelligence test was constructed by Alfred Binet20. He believed that intelligence was a dominant factor in determining school success and, as is not surprising, his belief was confirmed. His test predicted school grades with considerable success. This original test in its Stanford translation was the model for constructing later adult intelligence tests such as the Army Alpha and the WAIS. In these tests too, the criteria continued to be performance in some educational setting. In other words, adult intelligence testing continued in its emphasis on assessing educational aptitude.
Two serious problems arise however when we apply these kind of measures to adults. First of all, although the criterion of educational aptitude might be reasonable when applied to young adults, it is relatively meaningless for more elderly people who are for the most part far removed from academic settings. Secondly, adult tests such as the WAIS place a considerable premium on speed. As we have already seen, the slowing down of responding by older people means that they are unduly handicapped when coping with this kind of test.
There has been a move in recent years to tackle the first of these problems. Valid intelligence tests for use with adults must relate, in the words of Schaie21, 'to our coping in a competent manner with the problems of daily living'. That is, they should be constructed with real-life situations as the criteria. He and his colleagues22 are trying to develop what are termed ecologically valid tests for adults by trying to identify real-life situations that seemingly utilise intellectual competence.
Another effort to construct an intelligence test for adults removed from academic settings has been made by Gardner & Monge23. Their test has sub-test components dealing with knowledge about disease and death, about transport and about finance. Age differences on these sub-tests were found to be quite different from the age differences found on the more usual tests of intelligence. On one, the highest average score was obtained by men in their sixties. In addition, relatively little decline in average scores was found. The main problem remaining is that, as yet, nothing is known about how well scores on this test relate to performance by older people in real-life situations. The test seems promising however and it is to be hoped that ways will be found of determining its validity with respect to external criteria.
Apart from the question of the appropriateness of conventional intelligence tests as measures of adult cognitive ability, questions also arise about the differences in results from cross-sectional studies and longitudinal studies. Much of what is asserted about the relationship between age and intelligence has been based upon investigations using cross-sectional methods. Virtually without exception when this method is used younger people perform better. This decline by older people was originally interpreted as an age change. But in fact it can just as reasonably be interpreted as an age difference. There are a great many factors, educational, social, environmental and so on to account for the observed difference, it is not necessarily the ageing process itself.
Longitudinal studies almost always show less decline than cross-sectional ones. We can take as an example a famous one by Owens24. He did a follow-up study of men first tested on the Army Alpha in 1919. Thirty years later the men, now aged 50 showed significant gains and even eleven years later at age 61 they had non-significant losses. In Britain, a study by Nisbet25 showed similar results. This appears to be encouraging but a problem with longitudinal studies is they suffer from what is known as selective drop-out with lower ability adults tending to die off earlier or refusing to co-operate. This phenomenon has been corroborated in a number of studies and is known as terminal drop. A term first proposed by Kleemeier26. It refers to a dramatic decrease in adult cognitive ability prior to death. An example is a study by the Riegels27 in Germany. They tested 380 men and women in five age brackets from 55 to 75 and over. Two factors, a dramatic drop in score or a refusal to be re-tested were powerful predictors of death. Those who refused died sooner than co-operative subjects. The conclusions seem to be that if you are bright you don't mind showing it and that the bright seem to live longer. It is also fairly clear from the research that normal healthy adults can expect to be effective learners well into old age. The plotting of intelligence test scores against chronological age appears to be losing its appeal amongst gerontologists and there is a move towards looking at different aspects of cognitive functioning.
One aspect which has aroused a great deal or interest is Cattell's28 distinction between fluid and crystallised intelligence. Referring back to our nature-nurture controversy, fluid intelligence would be primarily nature and involve such abilities as memory span, spatial perception and speed tests, whereas crystallised intelligence would be more dependent on nurture and score heavily on non-speeded tests which call for knowledge and experience - tests such as vocabulary and general information.
Research, particularly by Horn29, one of Cattell's early collaborators and a pioneer in this field, shows that crystallised intelligence appears to increase or remain stable up to about age 60, or beyond that age if the person remains actively engaged in intellectual pursuits. Whereas fluid intelligence shows a different trend, starting high in the teens and declining to the sixties. One of the reasons for the appeal of these findings is probably their credibility in terms of commonsense. In everyday life we can often observe the quickness in learning of young people. Go to the nearest pub and watch them master the latest space-invader game. But we turn to older people when we require experience and judgement.
It is commonplace in the literature on adult education to read about older people compensating for the decline in quickness by substituting this experience and judgement. However, Schaie and Parr30have recently put forward the view that different stages of life might actually call for different learning abilities. School learning, with its emphasis on acquisition rather than application, capitalises on the strengths of young people. The processing and acquisition of large amounts of new information in the traditional school manner is, however, disadvantageous to older learners. The Educational model that would be appropriate for adults would be one in which emphasis was placed upon integration, interpretation and application of knowledge.
We turn now to the final part of this paper and have a brief look at another facet of cognitive functioning - that of memory. It is sad to comment, when looking at memory, that although psychologists have been studying human learning and memory for close on a century now, they can offer little in the way of practical advice that was not already common knowledge to the ancient Greeks. There is, of course, a vast amount of theory about basic processes but very little in the way of advice on improving our memories. Most models of memory are based upon the premise that it is composed of two types: short-term memory (STM) and long-term memory (LTM) each involving different neural mechanisms. Although there is some contrary evidence, most of the research reports, using cross-sectional methods, indicate that STM is poorer in older people than young ones. This fits in with the theory of fluid intelligence. If, however, the amount of new material to be stored is not too large or complex to scan efficiently, the deterioration is minor up to old age.
As far as LTM is concerned we find both supportive and non-supportive evidence that long-term memory is affected by age. A major difficulty in measuring prolonged LTM decline is the lack of a baseline. If we do not know how well the person knew the material to begin with, it is difficult to assess the decline.
It is interesting to note how the negative stereotype regarding older people comes into play again. If a young person forgets something it is regarded as perfectly normal and arouses hardly any comment. A similar lapse in an older person however frequently gives rise to comments about the decline of memory with age. This stereotype obviously has an effect on older people. An interesting study by Cavanaugh and Perlmutter31 who had subjects ranging in age from 20 to 60 years keep a diary of their memory lapses, showed that older subjects were much more upset by their failures than the younger ones. In fact no age difference was found in the frequency of reported memory failures. Many people, particularly older ones, think that their memory is much worse than it actually is. A recent study by Zarit, Cole & Guider32 found practically no correlation between complaints regarding bad memory and actual performance on laboratory memory tasks.
The research is sometimes conflicting but overall it is fairly clear that older learners appear to have the most difficulty in committing something to memory when the learning tasks are fast paced, complex, or require reassessment of old learning. However, adults with high verbal ability show less deterioration than those of low ability and it is important to keep in mind that the performance of some seventy-year olds can be equal to or superior to that of some people in their thirties.
Referring back to the title of this paper, it appears that the adage about old dogs not being capable of learning new tricks is, if taken at its face value, misleading. If one looks at the evidence it becomes clear that many old dogs are capable of learning a veritable host of new tricks and some of them are better at it than some young dogs! It is true that if one lives long enough, decrement in at least some of the cognitive abilities is likely to occur but this is by no means universal. What is virtually universal is the insidious concept of ageism which affects young and old alike. If it is generally accepted that old people are not capable of learning, discovering and stretching themselves intellectually, then it becomes eventually a self-fulfilling prophecy.
As professionals in adult education we should be at the forefront in this fight against ageism and should do everything we can to encourage older people that the excitement of learning and discovery is not confined solely to the young. I will finish with a phrase from a recent book by Eric Midwinter33, Director of the Centre for Policy on Ageing.
Those involved in the provision of education for older students should cheerfully accept that human intellectual apparatus can remain in good repair throughout its existence, showing a marked decline only at the very end of life when death is imminent. Possibly mental processes slow down with advancing age, but it would seem that the greatest handicap suffered by some elderly persons is disuse of mental apparatus.
Endnotes
- Masters, W., and Johnson, V., Human sexual response, Boston, Little, Brown, 1966
- Cutler, S., and Kaufman, R., 'Cohort changes in political attitudes', Public Opinion Quarterly, 1975, 39, pp. 69-81; Glen and Heiner, 1972
- Cutler, S. J., Lentz, S. A., Muha, M. J. and Riter, R. N., 'Ageing and conservatism: cohort changes in attitudes about legalised abortion', Journal of Gerontology, 1980, 35, pp. 115-123
- Blazer, D. & Palmore, E., 'Religion and ageing in a longitudinal panel', The Gerontologist, 1976, 16, pp. 82-83
- Palmore, E., 'Facts on ageing: a short quiz, The Gerontologist, 1977; Comfort, A., A good age, New York, Simon & Schuster, 1976
- Butler, 1969
- Bennett, R. & Eckman, J., 'Attitudes toward ageing: A critical examination of recent literature and improvements for future research' in C. Eisdorfer and M. P. Lawton (eds.), The psychology of adult development and ageing, Washington DC, American Psychological Association, 1973
- Weinberger, L. E. and Millham, J., 'A multi-dimensional, multiple method analysis of attitudes towards the elderly', Journal of Gerontology, 1979, 30, pp. 343-348; O'Connell, A. N. and Rotter, N. G., 'The influence of stimulus age and sex on person perception', Journal of Gerontology, 1979, 34, pp. 220-228
- Kausler, D. H., Experimental psychology and human ageing, New York, John Wiley, 1982
- Birren, J. E. and Schaie, K. W., (eds.), Handbook of the psychology of ageing, New York, Van Nostrand Keinhold, 1977; Kausler, op. cit.
- Allman, P., Adult development: an overview of recent research, University of Nottingham, Department of Adult Education, 1981
- Salthouse, T. A., 'Age and memory: strategies for localising the loss', in L. W. Poon, I. L. Fozard, L. S. Cermak, D. Arenberg and L. W. Thompson (eds.), New directions in memory and ageing, Hillsdale, N. J., Lawrence Erlbaum, 1980
- For a good review, see Klauser, op. cit.
- Waugh, N. C., 'Age-related differences in acquisition of verbal habit', Perceptual and Motor Skills, 1980, 50, pp. 435-438
- Nebes, R. D., 'Vocal versus manual response as a determinant of age difference in simple reaction time' Journal of Gerontology, 1978, 33, pp. 884-889
- Bloom, B. S., 'Mastery learning' in J. H. Block (ed.), Mastery learning: theory and practice, New York, Holt, Rinehart & Winston, 1971
- Knox, A. B., Adult development and learning: a handbook on individual growth and competence in the adult years for education and helping professions, San Francisco, Jossey-Bass, 1977
- Taylor, F. J., 'Acquiring knowledge from prose and continuous discourse', in M. J. A. Howe (ed.), Adult learning, New York, John Wiley, 1977
- Ausubel, D. P. and Robinson, F. S., School learning: an introduction to educational psychology, New York, Holt, Rinehart
- Binet, A. and Simon, T., 'The development of intelligence in children', L'Annee Psychologique, 1905, 163-191
- Schaie, K. W., 'External validity in the assessment of intellectual development in adulthood', Journal of Gerontology, 1978, 33, pp. 696-701.
- Schaie, op. cit.; Schaie, K. W. and Parr, J., 'Intelligence, in A. W. Chickering and associates, The modern American college, San Francisco, Jossey-Bass, 1981; Scheidt, R. J. and Schaie, K. W., 'A taxonomy of situations for an elderly population: generating situational criteria', Journal of Gerontology, 1978, 33, pp. 848-857.
- Gardner, E. F. and Monge, R. H., 'Adult age differences in cognitive abilities and educational background', Experimental Ageing Research, 1977, 3, pp. 337-383
- Owens, W. A. Jnr., 'Age and mental ability: a second follow-up', Journal of Educational Psychology, 1966, 57, pp. 311-325
- Nisbet, J. D., 'Intelligence and age: re-testing with twenty-four years' interval', British Journal of Educational Psychology, 1957, 22, pp. 190-198
- Kleemeier, R. W. (ed.), Ageing and leisure: a research perspective into the meaningful use of time, New York, Oxford University Press, 1961
- Riegel, K. F., Riegel, R. M. and Meyer, G., 'The prediction of retest resistors in research on ageing', Journal of Gerontology, 1968, 23, pp. 370-374
- Cattel, R. B., 'Theory of fluid and crystallised intelligence: a critical experiment', Journal of Educational Psychology, 1963, 54 (1), pp. 1-22
- Horn, J. L., 'Organisation of data on life-span development of human abilities', in L. R. Goulet and P. B. Baltes (eds.), Life-span developmental psychology, New York, Academic Press, 1970; Horn, J. L., 'Human ability systems', in P. B. Baltes (ed.), Life-span development and behaviour, Vol. 1, New York, Academic Press, 1978
- Schaie and Parr, op. cit.
- quoted in Klauser, op. cit.
- Zarit, S. H., Cole, K. D. and Guider, R. L., 'Memory training strategies and subjective complaints of memory in the aged', The Gerontologist, 1981, 21, pp. 158-164
- Midwinter, E., Age is opportunity: education and older people, Centre for Policy on Ageing, 1982
This document was added to the Education-line database on 22 May 2003
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