Age Differences in Recall and Recognition - American Psychological ...

Journal of Experimental Psychology: Learning, Memory, and Cognition 1987, Vol. 11, No. 3,474-479

Copyright 1987 by the American Psychological Association, Inc. 0278-739 3/8 7/$00.7 5

Age Differences in Recall and Recognition Fergus I. M. Craik and Joan M. McDowd

This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.

Erindale College, University of Toronto, Toronto, Ontario, Canada An experiment is reported in which young and elderly adults performed cued-recall and recognition tests while carrying out a choice reaction-time task. An analysis of covariance, with recognition performance as the covariate, showed a reliable age decrement in recall. It was therefore concluded that older people perform more poorly on recall tasks than they do on recognition tasks. Performance on the secondary (reaction time) task showed that recall was associated with greater resource "costs" than was recognition and that this effect was amplified by increasing age. The results are in line with the suggestion that recall requires more processing resources than does recognition and that such resources are depleted as people grow older.

The literature on age differences in human memory includes a large number of studies comparing the performance of young and old adults on tests of recall and recognition memory. The results of these studies have consistently shown an age decrement in recall performance (see Botwinick, 1978; Burke & Light, 1981; and Craik, 1977, for reviews), but they have been mixed with regard to recognition memory performance. Some studies have shown a significant age decrement in recognition (e.g., Erber, 1974; Gordon & Clark, 1974; White & Cunningham, 1982), whereas other studies have shown no such decrement (e.g., Schonfield & Robertson, 1966). However, the generalization can be made that age decrements are relatively smaller in tests of recognition memory than in tests of recall (Botwinick &Storandt, 1980; Craik, 1977; Schonfield & Robertson, 1966). This conclusion conceals two difficult methodological issues, however. The first is that younger and older people may adopt different guessing strategies in tests of recognition memory; the clear implication is that some bias-free measure of recognition, such as d', should be used (White & Cunningham, 1982). The second problem concerns the validity of comparing recall and recognition scores. Are the scales really comparable? For example, does a 20% difference in recall performance mean the same thing as a 20% difference in recognition memory performance? This second problem is clearly compounded by the first. How is it possible to compare age differences in percent recalled with age differences in recognition memory measured by d"? Arenberg (1985) has recently proposed an ingenious solution to this dilemma. He bypassed the problem of a common metric for the two retrieval tests by calculating the regression of recall on recognition for each age group separately, and then comparing the slopes of the regression lines for the different age groups. Arenberg used the mean number of words recalled from word

The research reported was supported by Grant A8261 from the Natural Sciences and Engineering Research Council of Canada. The authors are grateful to Robert S. Lockhart for comments on a previous version. Correspondence concerning this article should be addressed to Fergus I. M. Craik, Department of Psychology, University of Toronto, Toronto, Ontario, Canada M5S 1AI. 474

lists as the measure of recall performance, and A' (a nonparametric measure of sensitivity based on signal detection theory) as the measure of recognition memory. The argument is that if older people perform relatively poorly on recall tests compared with recognition tests, the slope of recall on recognition should be flatter for them. That is, for a given increment in recognition memory, older people should show a smaller increment in recall performance than that shown by younger subjects. In fact, Arenberg demonstrated that the slope of recall on recognition declined fairly systematically decade by decade from subjects in their 20s to people in their 70s and 80s. The conclusion that aging affects recall performance more than it affects recognition performance thus rests on a firmer base. Some questions still surround Arenberg's suggested method, however, and the problem of comparing the two retrieval tasks will be raised again in the Results section of the present article. Most researchers have attributed the differential age decrements in recall and recognition to the different retrieval demands of the two tasks (Arenberg, 1973; Burke & Light, 1981; Craik, 1977; Schonfield & Robertson, 1966). It has been suggested that recall involves more effortful processing than does recognition, and that older people are relatively penalized when such processing is required (Hasher & Zacks, 1979). In a variant of this position, Craik (1983) suggested that various retrieval tasks could be ordered with respect to the amount of "self-initiated processing" involved, that recall requires more self-initiated processing than recognition, and that older people are less able than their young counterparts to carry out such operations. That is, in a recognition test much of the empirical information is re-presented to the participant; appropriate mental operations are therefore driven largely by the external stimuli associated with the task itself. In recall by comparison, very few retrieval cues are provided and the participant must necessarily initiate appropriate mental operations in a more effortful manner. Craik's suggestion was that older people are relatively unimpaired on tasks involving either "automatic" processing (Hasher & Zacks, 1979) or a large degree of environmental support but show an age-related decrement in performance on tasks (like free recall) in which these features are absent. In turn, the greater impairment of self-initiated processing shown by older people may result from a reduction in available


RECALL, RECOGNITION, AND AGING processing resources with increasing age (Craik, 1983; Craik & Byrd, 1982; Rabinowitz, Craik, & Ackerman, 1982). However, there is an alternative account of the differential age-related losses in recall and recognition. It is well established that age decrements in performance are typically greater with more difficult or complex tasks (Cerella, Poon, & Williams, 1980; Welford, 1958), therefore the greater drop with age on recall tasks may simply reflect the fact that recall is usually a more difficult task than recognition. For example, Botwinick (1978) suggested that "perhaps it is not retrieval at all which accounts for the disparity among the age patterns (in recall and recognition), but simply the relative difficulty of the two tasks" (p. 342). Similarly, Salthouse (1982) has written that "at the present time it simply is not possible to determine whether older adults are at a greater disadvantage in recall tasks than in recognition tasks because the former have a greater retrieval component than the latter, or because the former is more difficult than the latter" (p. 142). But are these two accounts necessarily different? If recall requires a greater involvement of effortful, self-initiated processes than does recognition, presumably recall will appear to be the more "difficult" task, both phenomenologically and in terms of performance level. Rather than attempting to evaluate the relative merits of the "retrieval type" and "task difficulties" hypotheses, it may be more useful to establish further empirical relations to illuminate the problem, and that is the purpose of the present study. Specifically, one way of assessing the relative difficulty (in the sense of resource requirements) of recall and recognition tests is to compare their effects on a secondary task performed simultaneously with the retrieval task. If recall requires more resources than recognition, this difference should be apparent as a greater decrement in the secondary task when recall is the primary task than when recognition is the primary task. If older people have a smaller pool of processing resources, as was hypothesized by Craik and his colleagues, it should also follow that they should show a greater decrement in secondary task performance than their younger counterparts in such a study. This result was reported by Macht and Buschke (1983). Putting these various arguments and findings together, we should find that if younger and older people perform recall and recognition tasks in the secondary task paradigm, (a) older participants should exhibit greater losses in secondary task performance than the younger participants (Macht & Buschke, 1983), (b) all participants should show greater losses with recall than with recognition, but (c) older people should suffer differentially greater losses than their younger counterparts on recall as opposed to recognition tasks. That is, there should be an interaction between age and type of retrieval task in secondary task costs. Method In outline, subjects performed a continuous reaction time (RT) task either alone or while simultaneously retrieving words in tests of recognition or of cued recall. The continuous RT task carried out alone gave a baseline level of performance against which to measure the cost of performing the retrieval tasks. The continuous RT task (here termed the secondary task) was a four-choice task in which one of four classes of alphanumeric characters was shown visually, and the subject then pressed the corresponding response key as rapidly as possible. A correct

475

response caused the next visual character to be displayed immediately. The primary task, under dual-task conditions, consisted of either cued recall or recognition memory. In all cases, lists of 12 words were first presented visually to be learned by subjects under conditions of full attention; a descriptive phrase was presented along with each word. In the cued-recall task, the phrases were re-presented auditorily as cues; in the recognition task, the words themselves were re-presented auditorily, along with distractor words. It should be stressed that the continuous RT task was performed concurrently during retrieval only; the words and phrases for the memory tasks were presented alone in the encoding phase. An attempt was made to equate performance levels in the cued-recall and recognition tasks; this was accomplished by giving the cued-recall tests immediately following each list and delaying the recognition test until all lists had been presented and the recall tests performed. At a superficial level of analysis, task difficulty was approximately equated between recall and recognition by this means, although it must be conceded that difficulty is only loosely related to performance level. At a more practical level, the method ensured that floor and ceiling effects were avoided for both recall and recognition. It is important to note that Macht and Buschke (1983) found no differences in memory performance between single-task-control and dual-task conditions for either older or younger adults, which indicated that older adults are able to protect primary task performance even when required to perform a secondary task and, thus, that inferences made from the secondary task method are appropriate for both younger and older adults.

Subjects The younger participants were 15 Erindale college undergraduates who participated for course credit or for money. Mean age in the younger group was 20.7 years. The older participants were 15 men and women recruited from an existing subject pool of university alumni and volunteers from local senior citizens' centers. These older subjects were all living at home and came into the laboratory to be tested; for the most part they were retired middle-income people living in comfortable circumstances. Mean age for the older group was 72.8 years. All participants were reported to be in good health and had no uncorrected vision or hearing problems. The Mill Hill Vocabulary test was administered to both younger and older participants as a measure of verbal ability; mean scores were I4.2and 15.9 for younger and older, respectively. This difference was significant by i test, f(28) = 2.45, p < .05. The younger people had completed an average of 15.1 years (SD = 1.0 years) of formal education, and the older group had completed 12.2 years on average (SD = 3.1 years). This difference was also statistically reliable, f(28) = 3.47, p < .01. Interestingly, the older group had therefore been exposed to less formal education but had higher vocabulary scores.

Materials The to-be-remembered items in the present experiment were phrases and target words of the following sort: A body of water—pond. Sixty of these items were taken from those used by Craik and Tulving (1975), and an additional 84 were created by the experimenters with the requirement that the target word would not be the first thing to come to mind given the cue phrase. This assured that testing for memory of these items would be a test of episodic and not semantic memory. The total of 144 items was broken into 12 lists of 12 phrase-word items and presented visually one item at a time on a computer screen at a rate of 1 item/5 s. The first two lists were considered to be practice and the remaining 10, target lists. Of the 10 target lists, 5 were tested by immediate cued recall and 5 were tested by delayed recognition. That is, 60 words served as targets for cued recall and 60 different words


476

FERGUS 1. M. CRAIKL AND JOAN M. McDOWD

served as targetsforrecognition. The recognition test also used 60 completely new words as distractors: the 120 words (60 targets plus 60 distractors) were broken up into 10 lists of 12 words, with half of the words old and half of the words new in each list. The makeup of the recognition lists was randomly determined so that those items appearing together in the original presentation lists did not necessarily appear in the same block of recognition items. Recall and recognition tests were prerecorded and presented auditorily over headphones. For the recall test, the original cue phrases were recorded at a rate of 1 phrase/5 s, and the subject's task was to respond aloud with the corresponding target word in each case. For the recognition test, 10 blocks of 12 single words were recorded at a rate of 1 word/5 s and the subject's task was to respond "yes" or "no," depending on whether a given word had been in the presentation lists. Secondary task. The task to be performed concurrently with the retrieval tests was a four-choice reaction time task with a computer-generated display. The display was a single alphanumeric character, presented in the center of the computer screen. The four-choice decision was whether this character was a vowel or consonant if it was a letter, or an odd or even digit if it was a number. In front of the participant was a keyboard with four keys labeled, from left to right, vowel, consonant, odd digit, even digit; the task was to classify the character and press the appropriate key as quickly as possible. Each display remained on the screen until a correct response was made, at which time the screen cleared and a new display was presented. An equal number of characters were presented in each of the four classification categories, and order of presentation was random with the restriction that the same item was never presented more than twice in a row. If an incorrect key press was made by the participant, the same display was repeated until the correct response was made, and a cumulative RT was recorded. Display presentation and recording of RT's were accomplished with the use of a PDP11 computer. The measure of performance was simply the average RT throughout the retrieval interval. Retrieval tasks. In the cued-recall task, the descriptive phrases from the preceding list were presented auditorily over headphones at a rate of 1 phrase/5 s and in a different random order from the order of original presentation. The participant's task was to respond vocally with the word corresponding to each phrase during the 5-s interval. While they were recalling, they were also responding to the visual RT task. In the case of the recognition task, participants were presented with lists of single words; half of the words were target words and half were distractors, randomly mixed. The words were presented auditorily, over headphones, at a 5-s rate. The task was simply to respond "yes" or "no" depending on whether the word had been on any of the presented lists. Again, participants performed the visual RT task concurrently with the auditorily presented memory task. Participants' responses to the memory probes were recorded by the experimenter. Because both the recognition and the cued-recall tasks were presented in blocks of 12 items, each block lasted approximately 1 min.

Procedure All subjects were tested individually, starting with the visual RT task. The nature of the task was explained and each subject was given a minimum offiveblocks of 15 trials each as practice. Subjects continued to practice until they produced two consecutive blocks with mean RTs that differed by less than 100 ms. Once this was accomplished, the memory task was explained and participants were informed that they would perform the RT task while trying to remember the list items. Subjects were initially given one practice block with each of the retrieval tasks (cued recall and recognition) in combination with the RT task. In each case the subjectfirstlearned a list of 12 phrase-word items under conditions of undivided attention, and then performed the memory test for those items under dual-task conditions. At test, participants

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Figure 1. Left panel: Cued recall scores (proportion correct) and recognition scores (hits minus false alarms) as a function of age; right panel: RT costs (in milliseconds; mean dual-task RT minus mean baseline RT) as a function of age and retrieval task.

were instructed to consider the memory task to be the primary task and to perform the secondary task as quickly as they could without disrupting memory performance. After the 2 practice lists, participants proceeded through the rest of the lists and tests. Half of the lists, randomly chosen, were tested by cued recall and these tests took place immediately after presentation of the list. The recognition tests on the remaining 5 lists were administered after the participant had studied all 10 lists and completed all recall tests. Midway through the memory tests and again after all tests had been completed, participants were required to perform another block of the RT task by itself. Baseline measures of performance for each participant on the RT task performed alone were calculated from three blocks: the last practice block before the memory task, a block following the recall tests, and a block following the recognition tests. Results Figure 1 (left panel) shows the mean proportions of correct responses on the cued-recall task and mean recognition scores (hits - false alarms) for the two age groups. The figure shows that cued recall yielded somewhat higher levels of performance than did recognition in this case. Nevertheless, older participants did less well than the younger group on recall, whereas they performed slightly better than the younger participants in recognition. An Age X Test Type analysis of variance (ANOVA) on the accuracy data showed no significant main effect of age, F < 1.0, but a significant effect of test type, F{\, 28) = 29.57, p < .001, MSe = .011, which indicated that recall performance was significantly higher than recognition performance, and a significant Age X Test Type interaction, F(\, 28) = 8.07, p < .01, MSC = .011, indicating that the older participants performed less well, relative to the younger group, on recall than on recognition. Subsequent Scheffe tests revealed no reliable age difference on the recognition task, but they did reveal a reliable age decrement (p < .01) on recall. Table 1 shows the recognition results in greater detail; there were no reliable age differences (all ts < 1.0) in either hit rates, false alarm rates, or in d' scores. Although these results are in line with those of many previous studies, their interpretation is still subject to the difficulties discussed in the introduction: the desirability of taking some bias-

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RECALL, RECOGNITION, AND AGING

Table 1 Recognition Scores for Younger and Older Subjects Subjects

Hit rate (H)

False alarm rate (FA)

H - FA

d'

Younger Older

.76 .80

.14 .13

.62 .67

1.99 2.14


Note. Age differences were not statistically reliable for any measure.

free measure (such as d'} for recognition, and the consequent difficulty of comparing recall and recognition measures. In order to explore the applicability of Arenberg's (1985) proposal to the present data, d! scores were calculated for each subject; as is shown in Table 1 the means were 1.99 and 2.14 for younger and older subjects, respectively. The regressions of recall (measured as proportion correct) on recognition (measured as d') were then calculated for both age groups. The respective equations were, for the younger group, recall = 0.08 (d1) + 0.68, and for the older group, recall = 0.08 (d1) + 0.56. Product-moment correlations between the proportions recalled and d' were 0.61 and 0.51 for the younger and older groups respectively; the percentages of variance accounted for by the linear equation were 37% and 26%, respectively. Note that (contrary to Arenberg'sfindings)there was no age-related difference in regression slopes in the present case. Although Arenberg (1985) argued that the slope of the regression line for a particular age group can be interpreted as a measure of the relative effectiveness of recall compared with recognition for that group, his logic is perhaps open to question. Arenberg's argument is that "the slope of recall on recognition is dependent on the probability of recalling a recognized item, i.e., the more likely that a recognized item would be recalled, the steeper the slope. Therefore the recall/recognition slope should be steeper for the young than for the old" (p. 2). However, this argument assumes systematic age-related differences in the varying relation between recall and recognition within each age group. Specifically, the argument assumes that the differences in recall performance between "good recognizers" and "poor recognizers" will be greater for younger than for older groups. As far as we can see, there is no compelling reason to accept this assumption. On the contrary, from all that is known about the greater sensitivity of recall to cognitive impairment it might be assumed that the decrement in recall performance from good to poor recognizers might be greater for older subjects. The resolution of this problem is an empirical matter. For the

moment we suggest that a modification of Arenberg's idea may yield the required information. The question is, Do older people perform relatively less well than their younger counterparts on recall than on recognition tests? One way of answering the question is to ascertain whether for a given common value of recognition performance (measured say by d'), the older group performs less well than the younger group on recall. Rather than taking either the slopes or the intercepts of the regressions of recall on recognition as the measure of relative efficiency, we suggest carrying out an analysis of covariance (ANCOVA) to establish whether there are significant age differences in recall (measured as proportion correct) when recognition scores (measured as d') are taken as the covariate. This procedure statistically equates recognition performance, measured appropriately, and assesses age differences in recall performance given equivalent recognition performance. An ANCOVA on the present data, taking recall as the dependent measure, yielded adjusted mean recall scores of 0.86 and 0.73 for the younger and older groups, respectively; this age difference was highly reliable, F([, 27) = 14.78, p < .001, MSe = .01. Therefore, it may be concluded that the older group performed relatively less well than their younger counterparts on cued recall than on recognition memory. With respect to secondary task performance, a baseline measure wasfirstcalculated for each participant performing the visual RT task alone. Three measures of baseline performance were obtained in the course of the experimental session: initial baseline, postrecall baseline, and final baseline (see Table 2). For each subject, baseline for the recall task was taken to be the mean of the initial and postrecall single task trials; baseline for the recognition task was taken to be the mean of the postrecall and final single-task trials. By this procedure, the two components of each baseline measure preceded and followed the corresponding retrieval task. Difference scores were then calculated by subtracting these baseline RT scores from the RTs produced while performing the recall and recognition tasks under dual-task conditions (Table 2), These difference scores can be interpreted as representing the "cost" of performing each retrieval task. Figure 1 (right panel) shows the mean difference scores for each test type and age group. The figure shows substantially greater costs for the older group, especially in the case of recall. An Age X Test Type ANOVA carried out on the difference scores revealed a significant main effect of age, F(\, 28) = 9.43, p < .005, MSt = 291.79, which indicated that primary task perfor-

Table 2 Mean Reaction Times and Standard Deviations (in Milliseconds) for Younger and Older Subjects in Baseline (Continuous R T Task Alone) and Dual-Task Conditions Dual task

Baseline Final

Postrecall

Initial

Recognition

Recall

Subjects

RT

SD

RT

SD

RT

SD

RT

SD

RT

SD

Younger Older

823 1,244

159 218

658 1,010

145 221

585 920

157 288

1,135 2 ,140

319 859

945 1,573

319 444

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FERGUS I. M. CRAIK AND JOAN M. McDOWD


Table 3 Relative Divided Attention Costs as a Function ofAge and Retrieval Task Subjects

Recall

Recognition

Younger Older

.53 .86

.45 .52

mance costs were greater for the older than for the younger subjects; a significant main effect of test type, F(\y 28) = 14.41, p < .001, MSe = 83.98, which indicated that secondary task performance was significantly more inhibited during the recall task than during the recognition task; and a significant Age X Test Type interaction, F{\, 28) - 5.99, p < .02, MS* - 83.98, which indicated that the greater cost of performing recall relative to recognition was more pronounced for the older subjects than for the younger. Subsequent Scheffe tests (p < .05) revealed no difference in secondary task costs for the younger group between recall and recognition; the difference between the two retrieval tasks was significant in the case of older adults, however. In addition to these analyses, difference scores from the secondary task were also calculated as a proportion of single task RT levels. This procedure takes into account the age-related differences in the choice RT task performed by itself. A calculation (dual RT - single RT/single RT) was therefore performed for each participant on recall and recognition to yield measures of relative divided-attention (DA) costs (Somberg & Saithouse, 1982). These values are shown in Table 3. Relative DA costs were greater for the older group than for the younger group, and somewhat greater for recall than for recognition. An Age X Test Type ANOVA on the data yielded a marginally significant effect of age, JR(1, 28) = 2.94, p < .10, MSe = .21, a reliable effect of test type, f(l, 28) = 11,73,/? < .01, MSe = .05, which showed processing costs to be greater for recall than for recognition, and a significant Age X Test Type interaction, i^l, 28) = 4.67, p < .05, MSt = .05, which indicated that age differences in performance costs were greater for recall than for recognition tests, even when these costs were calculated as a proportion of singletask performance levels. Discussion The present experiment has illustrated a number of points concerning age differences in recall and recognition. First, performance on the concurrent RT task confirmed Macht and Buschke's (1983)findingof an age-related decrement in secondary task performance in a dual-task situation. More important, cued recall was more disruptive to secondary task performance than was recognition memory, and this effect was greatly amplified in the older group. We conclude that recall tasks demand more processing resources than do recognition tasks and that because older people have a smaller pool of processing resources at their disposal, they are disproportionately penalized. In the present results at least, the older group performed significantly less well than their younger counterparts both on the RT task performed concurrently with recall, and on the recall task itself. Second, when recognition scores were expressed as d' values

and recall was expressed as proportion correct, an ANCOVA showed a significant age decrement in recall, with d1 scores taken as the covariate. That is, when recognition performance was statistically equated between the age groups, an age decrement was found for cued recall. We interpret this result as showing that older people perform relatively less well than younger controls on tasks of recall compared with tasks of recognition, even when recognition performance is measured appropriately by d' scores. The ANCOVA method provides an answer to workers such as White and Cunningham (1982) who have urged researchers to resolve the ambiguities surrounding the relations among recall, recognition, and aging. Third, does thefindingof relatively greater age losses in recall than in recognition fit the general scheme that older people perform relatively poorly on any difficult task (Botwinick, 1978; Saithouse, 1982)? At one level of description the present results do fit that scheme. The recall task was more disruptive to the concurrent continuous RT task than was the recognition task and the effect was enhanced in older subjects. In a sense then, recall was more "difficult" than recognition and this was especially true for the older group. But "difficulty" is an unsatisfactory concept because it involves and possibly confuses different levels of analysis: phenomenological feelings of difficulty, the mental effort required to perform the task satisfactorily, and the resulting performance level. We therefore prefer to interpret the results from the present study as showing that recall tasks require more self-initiated activity or more processing resources than do recognition tasks, and that older people are therefore at more of a disadvantage when recall is involved. This account is in line with Hasher and Zacks's (1979) suggestion that older people are differentially penalized as tasks become less automatic and more effortful. It is also in line with Craik's (1983) notion that memory retrieval tasks may be ordered from those (like free recall) requiring a great deal of selfinitiated activity to those (like recognition and priming tasks) requiring little or none, and that age decrements are a function of the degree of self-initiated activity required (see also Light & Singh, in press). Finally, the present results are also compatible with the notion that processing resources decline with advancing age (Craik, 1983;Craik&Byrd, 1982) and that the different patterns of age-related decrements associated with different memory tasks may be attributed to this underlying concomitant of the aging process.

References Arenberg, D. (1973). Cognition and aging: Verbal learning, memory and problem solving. In C. Eisdorfer & M. P. Lawton (Eds.), The psychology of adult development and aging (pp. 74-97). Washington, DC: American Psychological Association. Arenberg, D. (1985). The problem of comparing recall and recognition in young and old adults. Manuscript submitted for publication. Botwinick, J, (1978). Aging and behavior {2nd Ed.). New York: Springer. Botwinick, J., & Storandt, M. (1980). Recall and recognition of old information in relation to age and sex. Journal of Gerontology, 35, 7 0 76. Burke, D. M., & Light, L. L. (1981). Memory and aging: The role of retrieval processes. Psychological Bulletin, 90, 513-546. Cerella, J., Poon, L. W., & Williams, D. M. (1980). Age and the complexity hypothesis. In L. W. Poon (Ed,), Aging in the nineteen-eight-


RECALL, RECOGNITION, AND AGING ies: Psychological issues (pp. 332-340). Washington, DC: American Psychological Association. Craik, F. I. M. (1977). Age differences in human memory. In J. E. Birren & K. W. Schaie (Eds.), Handbook oj the psychology of aging (pp. 384420). New York: Van Nostrand Reinhold. Craik, F. I. M. (1983). On the transfer of information from temporary to permanent memory. Philosophical Transactions of the Royal Society, London, SeriesB, 302, 341-359. Craik, F. I. M., & Byrd, M. (1982). Aging and cognitive deficits: The role of attentional resources. In F. I. M. Craik & S. Trehub (Eds.), Aging and cognitive processes (pp. 191-211). New York: Plenum Press. Craik, F. I. M., &Tulving, E. (1975). Depth of processing and the retention of words in episodic memory. Journal of Experimental Psychology: General, 104, 268-294. Erber, J. T. (1974). Age differences in recognition memory. Journal of Gerontology, 29, 177-181. Gordon, S. K., & Clark, W. C. (1974). Application of signal detection theory to prose recall and recognition in elderly and young adults. Journal of Gerontology. 29, 64-72. Hasher, L., & Zacks, R. T. (1979). Automatic and effortful processes in memory. Journal of Experimental Psychology: General, 108, 356388.

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Light, L. L., & Singh, A. (in press). Implicit and explicit memory in young and older adults. Journal of Experimental Psychology: Learning, Memory, and Cognition. Macht, M. L., & Buschke, H. (1983). Age differences in cognitive effort in recall. Journal of Gerontology, 38, 695-700. Rabinowitz, J. C , Craik, F. I. M., & Ackerman, B. P. (1982). A processing resource account of age differences in recall. Canadian Journal of Psychology, 36, 325-344. Salthouse, X A. (1982). Adult cognition: An experimental psychology of human aging- New York: Springer-Verlag. Schonfield, D., & Robertson, B. A. (1966). Memory storage and aging. Canadian Journal of Psychology, 20, 228-236. Somberg, B. L., & Salthouse, T. A. (1982). Divided attention abilities in young and old adults. Journal of Experimental Psychology: Human Perception and Performance, 8, 651-663. Welford, A. T. (1958). Ageing and human skill. London: Methuen Press. White, N., & Cunningham, W. R. (1982). What is the evidence for retrieval problems in the elderly? Experimental Aging Research, 8, 169-171.

Received October 11, 1985 Revision received July 20, 1986 Accepted July 31, 1986 •