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The effect of stimulus and response meaningfulness when response availability is equated
JOURNAL OF VERBAL L E A R N I N G
AND
VERBAL BEHAVIOR 2, 242-249 (1963)
The Effect of Stimulus and Response Meaningfulness When Response Availability Is Equated WILLIAM EPSTEIN 1
University o/Kansas, Lawrence, Kansas
It is generally found that variations in meaningfulness (M) are more effective when they occur on the response side than on the stimulus side (cf. Underwood and Schulz, 1960, pp. 35-42, for a review). One way of accounting for this finding is to-assume that variations of response-M can influence both the response-recall stage and the associative stage, whereas, variation of stimulus M can affect the associative stage only. This interpretation leads to the expectation that if the necessity for response-learning were eliminated, then the effect of M would be equivalent for variations on the stimulus and response side. Some evidence for this expectation was provided in an experiment by Epstein and Streib (1962). The acquisition of lists of Lo M - H i M pairs and 'turned over' Hi M-Lo M pairs was compared under three conditions. Condition A was anticipatory learning which requires both response-learning and associative learning. Under this condition List Lo-Hi was acquired in half the number of trials required for List Hi-Lo. Conditions Re and Rd were easy and difficult tests of recognition. Under these conditions response-learning was not necessary since the correct response was present at the time of testing. The rates of learning Lists Lo-Hi and Hi-Lo were identical under Condition Re, in agreement with the theoretical expectation. However, under Condition Rd, List Hi-Lo 1 Grateful acknowledgment is made to Rachel Streib for her assistance in collecting the data a n d performing the statistical analyses.
was learned twice as rapidly as List Lo-Hi, which represents a reversal of the usual finding. This latter result suggested that when response learning is equated stimulus-M exercises a powerful influence on learning. Presumably, the effect of stimulus-M could not be discerned under Condition Re because both lists were acquired very rapidly. The present experiment was a reexamination of the two-stage analysis of the relative effects of stimulus and response M with a new technique for eliminating differences in response-availability. The recognition test used in the earlier study entailed various interpretive difficulties which made it desirable to employ a different method. In addition, the present design included conditions for testing the implication derived from the result for Rd concerning the influence of stimulus M. The general plan of the main experiment was to compare the anticipatory.learning of lists of Lo-Lo, Lo-Hi, Hi-Lo, and Hi-Hi pairs when response-availability was equated for all lists. Following the lead of Underwood et al. (1959) and Asch and Ebenholtz (1962a, 1962b) response-availability was defined by the operations of free recall. In other words, if an item was produced by S on a test of free recall, then the item was considered to be available. The experiment was performed in two phases. In the first phase a series comprised of the items later to serve as responses in paired associate lists was presented. After each presentation of the list S was asked to reproduce the list orally by free recall. This 242
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was continued ufltil S successfully reproduced the entire list. I m m e d i a t e l y following the completion of this task, S commenced the anticipatory learning of a list of pairs whose responses were the items learned in free recall. I n order to assess the effect of prior response-learning, four additional groups learned the same lists without prior response-learning.
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Subjects. The Ss were 16 undergraduate summer session students at the University of Kansas. None of them had participated previously in experiments on verbal learning.
Procedure. Five high-M (mean ~-5.40) and five low-M items (mean z 1.40) were selected from the pool of items later to be used as responses in the paired-associate task of the main experiment. These items were presented serially in a memory drum at a 2-see rate. The S was instructed to learn the items for the purpose of reproducing them in free recall. The items were presented in five different random orders. The same order was not repeated on successive trials, After each presentation of the complete list S was allowed 1 rain in which to reproduce the items orally in any order he wished. The E recorded S's responses in writing and permitted S to see the record as it was being produced. The criterion of mastery was complete recall of all 10 items. Immediately following the criterial trial, the M values of the items were determined for each S. For this purpose Noble's (1952) production method was used. Every effort was made to duplicate Noble's operations exactly. The records were then scored by an independent judge who was not familiar with the M values of the items or the purpose of the experimental operations.
Results. T h e mean number of trials to total recall for the 16 Ss was 4.38 ( S D - ~ 2.25). W h e n the two types of items were considered separately, it was found t h a t the mean numbers of trials were 4.82 (SD ~ 1.35) and 4.00 ( S D - ~ 1.34) for the five high-M and five low-M items, respectively. This difference is not statistically significant. T h e d a t a for two Ss were discarded in the analysis of the results of the production method. I n s t e a d of responding to the stimulus-item these Ss persisted in "free-associating." Therefore, the post-learning M values were based on the d a t a of 14 Ss. T h e M values of all the items were somewhat higher after item-learning than before. However, the relative status of the high and low items was unaffected b y the prior learning. This l a t t e r observation was confirmed b y two statistical analyses. A t test of the difference between the high(mean z 8.37) and low-M (mean ---- 3.43) items alter learning yielded a value of 8.41 (p < .01, d] ~ 13). I n addition, a Spearman r a n k order correlation of 0.94 (p < .01) was obtained between the M values of the 10 items as given b y Noble (1952) and the M values derived from the number of associates produced b y our Ss after learning. Conclusion. N o evidence was obtained to indicate that item-learning in a free-recall situation affects the relative M values of the items. 3 There was not a single instance in which a low-M item received a higher-score than a high-M item. T h e difference between the higest of the low-M items and the lowest of the high-M items was 3.31 on Noble's list and 3.07 after item-learning. Although these findings answer the question
2 Riley and Phillips (1959) have shown that prefamiliarization does not alter relative associative values. However, their conditions were sufficiently different from ours as to make a new test desirable.
3 The absence of a differential effect of item learning on M values was also demonstrated in an unreported experiment in which different groups of Ss learned homogeneous lists of high- or low-M items.
PRELIMINARY EXPERIMENT A Prior to the main experiment a p r e l i m i n a r y s t u d y was performed to explore an i m p o r t a n t methodological question. W h a t is the effect of item-learning, under conditions of free recall, on the M values of the items? 2 I n particular we needed to know whether the relative M values of the low- and high-M response items remained intact after item-learning. I t is obvious, t h a t if item-learning resulted in uncontrolled modifications of M, then itemlearning could not be employed for the present purposes.
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for which the experiment was designed, they introduce a new interpretive difficulty which warrants comment. The experiment demonstrated that item-learning produces comparable changes of M for low- and high-M items. There is some evidence that the differences in learning associated with variations Of M depend on whether the variations are in the lower or higher range of the scale of M. However, the precise character of this relationship is still in doubt. Some studies show a tendency toward positive acceleration of rate of acquisition with increasing meaningfulness, others have shown a trend toward negative acceleration, still others have conjectured that the relationship between difficulty and M might be sigmoid (reviewed by Underwood and Schulz, 1960, Chap. 3). Nevertheless, it must be noted that if greater differences in learning are produced by variations in the lower range than by comparable scale differences in the upper range, then the changes in M produced by item-learning would reduce the difference between the acquisition rates for the lists which differ in response-M. Therefore, a potential confounding must be recognized. PRELIMINARY EXPERIMENT B An additional question which required investigation prior to the main experiment concerned the short-term retention of highand low-M items learned to the same criterion of free recall. It is generally found in serial and paired-associate learning that rate of acquisition is one of the factors which determines retention. Thus, if an easy and difficult series of items are learned to the same criterion of mastery, but at different rates, then an early test of retention will usually reveal differences between the two lists. It is generally the case that high-M items are learned more rapidly than low-M items. 4 Therefore, 4 This was not the case in Experiment A, although the direction of the difference was consistent. Perhaps the failure to find a difference is due to the fact that a mixed list was used.
despite prior response-learning the high- and low-M items may not be equally available as responses at the beginning of the pairedassociate task in the main experiment. The purpose of Experiment B was to examine this question under conditions identical to those of the main experiment. Subjects. Twenty students from the same population which provided Ss for Experiment A and the main experiment served as Ss. They were assigned alternately to two groups in the order with which they appeared for the experiment. Procedure. In order to make the procedure identical with that of the main experiment, each S began with trials on a practice list of 4 pairs of adverbs. Following this, Ss in Group Lo learned the 10 low-M items which served as responses in the Lo-Lo and Hi-Lo lists of the main experiment. Group Hi learned the 10 high-M items assigned as responses to the Lo-Hi and Hi-Hi lists of the main experiment. The procedure and criterion of mastery were the same as in Experiment A. Following the criterial trial, Ss were read the instruction for paired-associate learning given to the Ss in the main experiment. This usually entailed an interval of 2 rain. Then Ss were asked to reproduce the list of 10 items in free recall. One minute was allowed for the test. Results. The mean number of trials to mastery in free recall was 3.54 (SD z 1.63) and 10.27 (SD ~ 4.90) for Group Hi and Group Lo, respectively. This difference is highly significant (t ---~4.31, df ~ 18, p .01). The mean number recalled after the paired-associate instructions was 9.36 (SD - 0.92) and 9.09 (SD ~ 0.83) for Group Hi and Group Lo, respectively. This difference does not approach significance. Conclusion. Short-term retention of items learned under the present conditions of free recall is very high and does not differ for high- and low-M items. We conclude, therefore, that the high- and low-M items learned to the same criterion of free recall in the main experiment will be equally recallable qua items when paired-associate learning is initiated. We would also presume that the slight retention loss obtained in the present experiment would be erased by the initial presentation of the responses on the first trial
RESPONSE AVAILABILITY of t h e p a i r e d - a s s o c i a t e list. T h i s w o u l d enh a n c e t h e r e c a l l a b i l i t y of t h e r e s p o n s e - i t e m s a t t h e t i m e of t h e first t e s t t r i a l i n t h e m a i n experiment. MAIN EXPERIMENT I n t h i s e x p e r i m e n t t h e a c q u i s i t i o n of L o - L o , L o - H i , H i - L o , a n d H i - H i lists w a s c o m p a r e d with and without prior response learning. The following were the main predictions c o n c e r n i n g t h e effects of p r i o r i t e m l e a r n i n g : ( 1 ) P r i o r i t e m l e a r n i n g s h o u l d f a c i l i t a t e acq u i s i t i o n of all f o u r lists. ( 2 ) W h e n s t i m u l u s M is c o n s t a n t , p a i r s c o m p r i s e d H i M a n d L o M
responses
learning.
should
(3) When
not
differ i n
ease
of
r e s p o n s e - M is c o n s t a n t ,
pairs with Hi M stimuli should be acquired more rapidly than pairs with Lo M stimuli. ( 4 ) T h e difference in p e r f o r m a n c e for t h e p a i r s w h i c h differ in s t i m u l u s - M s h o u l d b e l o c a l i z e d in t h e a s s o c i a t i v e s t a g e of l e a r n i n g .
MaLerlals. Twenty Lo M and 20 Hi M items were selected from Noble's (1952) list. The mean values of the items were 1.43 (SD ~ 0.27) and 6.67 (SD 1.31) for the Lo M and Hi M items, respectively. These were formed into four lists of 10 pairs each. List Lol-Lo 2 consisted of pairs composed by combining the Lo M items. The mean difference between the M values of the stimuli and responses comprising each pair in List Lol-LO 2 was 0.04. List LOl-Hi 2 consisted of the same stimuli paired with Hi M responses. The mean difference between the M values of the stimuli and responses in this list was 5.28 (SD ~-1.03). List Hil-Lo 2 was comprised of the responses in List LOl-LO 2 paired with Hi M stimuli. The mean difference between the M values for the stimuli and responses was 5.25 (SD ~-1.10). List Hil-Hi 2 was composed of the stimuli used in List Hil-Lo 2 paired with the remaining 10 Hi M items. The mean difference between the M values of the stimuli and responses in List Hil-Hi 2 was 0.01. In the construction of the pairs care was exercised to avoid any obvious associational linkages. The above procedure for construction of the Lo-Hi and Hi-Lo pairs departs from the convention of using the same items on both sides, i.e., LOl-Hil, Hii-Lo 1. This procedure was abandoned in order to achieve complete identity for the variables which were held constant in the main comparisons (see second and third predictions). This is not possible with the typical procedure which counterbalances
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S and R items. In the counterbalanced design, either the equivalent-M responses must be different, or the equivalent-M stimuli must be different.
Subjects. Eighty-eight students from the same population as in the preliminary study served as Ss. The first 44 Ss were divided into blocks of 4 each in order of their appearance for the experiment. Within each block, 1 S was randomly assigned to each of the 4 experimental conditions. The next 44 Ss were assigned in the same manner to the 4 control conditions. Thus there were 8 groups of 11 Ss each.5 Procedure. Each S began with five practice trials with a list of four trisyllabic adverbs. The conventional method of anticipation was used. This practice task provided a basis for assessing initial learning ability, and also served to reduce the confusion and consequent variability which otherwise occurred when S was switched from free recall of a series to paired-associate learning. Upon completion of the practice task S learned the 10 response items of his assigned paired-associate list. The free-recall procedure employed in the preliminary studies was followed again. Learning was continued to the criterion of complete recall. Immediately following the criterial trial, S began learning the paired-associate list. The list was exposed on a memory drum at a 2."2 sec rate with a 4-see intertrial interval. Five different orders of presentation were used. None of the five orders presented the responses in an order identical to that which obtained during the prior item-learning. The S was instructed to pronounce all the items aloud and guessing was encouraged. The procedure for the four control conditions was the same as that of the experimental conditions with one important exception: there was no prior responselearning. Instead, these Ss worked on number-completion tasks. The amount of time allowed for these filler tasks was the average time required for responselearning by their respective experimental groups. Results. T h e t o t a l n u m b e r c o r r e c t for t h e l a s t t w o trials o n t h e p r a c t i c e list was d e t e r m i n e d for e a c h S. T h e m e a n s w e r e 4.36 (SD : 2 . 0 1 ) , 2.91 ( S D - ~ 1.70), 5.00 ( S D - 2 . 7 9 ) , a n d 4.09 ( S D z 2.26) for t h e i t e m l e a r n i n g g r o u p s a s s i g n e d to L i s t s L o - L o , H i Lo, L o - H i , a n d H i - H i , r e s p e c t i v e l y . T h e m e a n s w e r e 3.45 ( S D ~ 2 . 4 7 ) , 3.49 ( S D z 2 . 4 7 ) , 5 The desirability of the control conditions became apparent only alter the experiment was begun. Therefore, the atypical procedure of running the control Ss after the experimental Ss.
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4.28 (SD.~ 1.63), and 3.87 (SD = 2.28) for the groups without item-learning assigned to the corresponding lists. A 2 X 2 X 2 analysis of variance of the data for the last two trials shows that none of the main effects (item-learning, stimulus-M, response-M) or interactions are statistically significant. This indicates that the Ss in the eight groups were comparable in palred-associate learning abifity at the outset of the experiment. Next, the item-learning scores for the Lo M and Hi M items were compared. The mean number of trials was 3.32 (SD--2.01) and 7.78 (SD--4.31) for the Hi M and Lo M items, respectively. This difference is highly significant (t - - 4.41, d] ~ 42, p ~ .01), confirming the findings of Experiment B. TABLE I
MEAN NUMBER OlP TRIALS TO MASTERY W I T H A N D WlTI-IOUT PRIOR R E S P O N S E - L E A R N I N G
With prior response learning
Without prior response learning
Lists
Mean
SD
Mean
SD
Lo-Lo Lo-Hi Hi-Lo Hi-Hi
16.64 8.27 14.73 7.64
7.43 3.58 12.56 7.72
23.36 8.91 21.27 10.54
3.47 2.43 8.11 7.85
Table 1 presents the mean trials to mastery of the four paired-associate lists with and without prior response-learning. A 2 X 2 X 2 analysis of variance shows that the condition of prior training, i.e., item-learning, is a significant source of variance (F--~ 7.22, d]-1/80, p < .01). There were no significant interactions between this variable and stimulus-M or response-M. Prior item-learning facilitated acquisition independently of variations in stimulus- or response-M. Inspection of Table 1 shows that although prior item-learning reduced the differences between the lists it did not alter the relative speeds of acquisition. Neither the second nor third prediction, which were derived from the two-stage analysis, was confirmed. The analysis of variance showed that response-M was
a significant source of variance (F ~-42.16, d / - - 1 / 8 0 , p ~ .01). However, the interaction of response-M with stimulus-M did not approach significance. In addition, responseM did not interact significantly with the conditions of prior training. The facilitating effect of high response-M was independent of stimulus-M and prior item-learning. On the other hand, sfimulus-M was not a significant source of variance. Nor was there a significant interaction of stimulus-M and condition of prior learning. Thus no evidence was obtained in support of our prediction that with response-M constant, variations in stimulus-M would influence speed of acquisition. The next index of performance which was analyzed was the trial on which a response first occurred regardless of placement. This index is often taken as a measure of the first stage of associative learning (e.g., Postman, 1962). One would expect that response occurrence would be earlier following item-learning, and that prior item-learning would eliminate the differences between Hi M and Lo M responses in this regard. Table 2 presents the means for the trials to initial response occurrence for the four lists under both conditions of training. The training variable proved to be a significant source of variance (F z !7.55, d] z 1/80, p < .01). Prior item-learning produced earlier response occurrence. The effect of response-M was also significant (F ~ 45.91, d ] z 1/80, p ~ .01). The Hi M responses occurred earlier than the Lo M responses. In addition, there was a significant interaction of response-M with condition of prior training (F ~ 5.43, 1/80, p ~ .05). Inspection of Table 2 shows that the difference between the Ix) M and Hi M responses was smaller when item-learning preceded the associative task. Duncan's new multiple range test with a .05 was used to make individual comparisons among the four relevant means (Edwards, 1960, pp. 136-140). Four of the six differences were significant. The mean for the group
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RESPONSE AVAILABILITY TABLE 2 MEAN TRIALS TO INITIAL OCCURRENCE OF RESPONSE AND MEAN DIFFERENCE BETWEEN TRIAL O1~ INITIAL RESPONSE OCCURRENCE AND TRIAL OF FroST CORRECT PAIRING
Differencebetween initial response occurrenceand first correct pairing
Trials to initial response occurrence
Lists Lo-L o Lo-Hi Hi-Lo Hi-Hi
Item learning Mean SD 4.43 2.73 3.83 2.14
1.37 1.02 2.44 2.14
No item learning Mean SD 7.35 3.47 5.87 2.81
which learned pairs containing Lo M responses without prior item-learning was significantly greater than each of the other means. The mean for the group which learned the pairs containing Lo M responses after item-learning was significantly greater than the mean for the group which received Hi M responses after item-learning. Therefore, while the difference between the initial occurrence of Hi M and Lo M responses was reduced by prior item-learning, Hi M responses continued to occur significantly earlier. Also, contrary to expectation, stimulus-M was a significant source of variance (F - - 4.78, d] -~- 1/80, p < .05). On the average, high stimulus-M yielded earlier response-occurrence. There were no significant interactions between stimulus-M and the other variables. Table 2 also shows the mean difference between trial of initial response occurrence and the first correct pairing. This difference provides an estimate of the length of the associative stage. The analysis of variance of these data showed only one significant main effect and no significant interactions. Neither stimulus-M nor the conditions of prior training had a significant effect on the difference scores. Only response-M remained a significant variable (F--- 12.91, d]~- 1/80, p < .01). The differences between the trial of initial response occurrence and first correct pairing were smaller for the pairs containing the Hi M
1.97 0.93 3.20 0.84
Item learning Mean SD 0.99 0.42 1.66 0.31
0.86 0.45 1.58 0.62
No item learning Mean SD 0.76 0.37 1.75 0.46
0.65 0.34 1.56 0.38
responses. This finding does not conform to the prediction derived from the two-stage theory. Several auxiliary comparisons are also relevant to the theoretical interpretation under examination. These involve comparisons between lists containing responses of different M value when learned with and without prior item-learning. Does item-learning facilitate the lists containing Lo M responses so that they are acquired as rapidly as the lists containing Hi M responses but without prior item-learning? For this purpose List Lo-Lo and list Hi-Lo preceded by item learning can be compared with List Lo-Hi and List Hi-Hi, respectively, without prior item-learning. An inspection of Tables 1 and 2 shows a general tendency in favor of Lists Lo-Hi and List HiHi. Thus, despite the fact that the Lo M response items were made highly available by recent item-learning the superiority of high response M was not eliminated. DISCUSSION
The results of the main experiment provided general support for the two-stage analysis of associative learning. This conclusion is supported by the finding that prior item-learning facilitated acquisition of pairs containing these items as responses. This support needs to be qualified due to the absence of a basis for comparing the response-learning condition
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with a stimulus-learning and an irrelevant item-learning condition. The force of this qualification is mitigated somewhat by the fact that item-learning did not affect all of the performance measures. Item-learning facilitated overall mastery mainly by producing earlier response-occurrence. It did not significantly affect the speed with which the response was correctly associated with the stimulus. Thus, the effect of item-learning was observed in the response-learning stage only, in agreement with the implications of the two-stage theory. The experimental findings did not support the two-stage analysis as it applies to the influence of M on associative learning. However, in view of the demonstrated usefulness of this analysis in relation to other questions, it will be prudent to reexamine the present study before reaching a final conclusion. The basic premise of the experimental rationale was that high- and low-M items which initially differed in availability could be equated in this regard by prior item-learning. In retrospect, there are two arguments which can be raised concerning this premise. First, it is possible that availability in free recall does not guarantee response recall under conditions of paced anticipation. In the former case, S is set to produce items qua items. In the latter situation, S is set to produce responses in their prescribed place, and in a temporal order governed by the order of stimulus presentation. A second argument might be that the nonsense disyllables which served as the Lo M items could not have been expected to become equal in availability to the real words which served as the Hi M items. In support of these arguments is the finding that, despite prior item learning, Hi M items occurred as responses earlier than Lo M items. An experiment to remedy these possible shortcomings would include the following features: (1) item availability would be produced under conditions in which the items functioned as responses to stimuli; (2) none of the items would be real words; and (3) re-
sponse availability would be checked at various stages during the learning of the critical list of pairs. In addition to their bearing on the question of M and associative learning the present findings may have implications for the general two stage-analysis. In particular, the data on initial response occurrence suggest that there may be variables other than item recallability which can determine the speed with which an item occurs as a response somewhere in the list of pairs. In other words, response occurrence may not be a valid indicator of the termination of the first stage. Response learn•ng may occur without response performance. This would tend to limit the usefulness of the two-stage distinction in the analysis of data. SUIVflVfARY
The main purpose of this study was to examine the effects of stimulus-M and response-M on paired-associate learning when the low- and high-M responses are made equally ~/vailable. The procedure for equating response availability consisted of learning the response items in random serial order to a criterion of complete free recall. Immediately following the criterial trial, S learned a list of paired associates by the method of anticipation. Preliminary Experiments A and B were concerned with some basic effects of itemlearning. The results of Experiment A showed that item-learning under conditions of free recall does not affect the relative M values of low- and high-M items. Experiment B showed that low- and high-M items are equally available in short-term retention despite the fact that low-M items are acquired in free-recall learning at a much slower rate than high-M items. The main experiment compared the acquisition of Lo-Lo, Lo-Hi, Hi-Lo and Hi-Hi lists with and without prior response-learning. A different group of 11 Ss was assigned to each of the eight conditions. These main predictions concerning the effects of prior item-
RESPONSE AVAILABILITY learning were derived from the two-stage analysis of associative learning: (1) prior item learning should facilitate acquisition of all four lists; (2) when stimulus-M is constant, pairs comprised of Hi M and Lo M responses should not differ in ease of learning; (3) when response-M is constant, pairs with Hi M stimuli should be acquired more rapidly than pairs with Lo M stimuli; (4) the difference in performance for the pairs which differ in stimulus M should be localized in the associative stage of learning. Analyses were performed of the trials to criterion, trials to first response occurrence regardless of placement, and the difference between the trial of initial response occurrence and first correct pairing. Only the first prediction given above was supported. The results were discussed as they relate to the two-stage analysis of associative learning. REFERENCES
ASCII, S. E., AND EBENIIOLTZ, S. M. The principle of associative symmetry. Proc. Amer. Philo. Soc.,
1962, 106, 135-163.
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Ascii, S. E., AND EBENHOLTZ, S. IVY.The process of free recall: Evidence for nonassociative factors in acquisition and retention. J. Psychol., 1962, 54, 3-31. EDWARDS,A. L. Experimental design in psychological research. New York: Rinehart, 1960. EPSTEIN, W., AND STREIB, R. The effect of stimulus meaningfulness and response meaningfulness in the absence of response learning. J. verb. Learn. verb. Behavior, 1962, 1, 105-108. NOBLE, C. E. An analysis of meaning. Psychol. Rev., 1952, 59, 421-430. POSTMAN, L. The temporal course of proactive inhibition for serial position. J. exp. Psychol., 1962, 63, 361-369. RILEy, D. A., AND PIIILLIPS, L. W. The effects of syllable familiarization on rote learning, association value, and reminiscence. J. exp. Psychol., 1959, 57, 372-379. UNDERWOOD, B. J., RUNDQUIST, W. R., AND SCHUIaZ, R. W. Response learning in paired-associate lists as a function of intralist similarity. J. exp. Psychol., 1959, 58, 70-78. UNDERWOOD, B. J., AND SCHIYLZ, R. W. Meaningfulness and verbal learning. Philadelphia: Lippincott, 1960. (Received December 26, 1962)
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VERBAL BEHAVIOR 2, 242-249 (1963)
The Effect of Stimulus and Response Meaningfulness When Response Availability Is Equated WILLIAM EPSTEIN 1
University o/Kansas, Lawrence, Kansas
It is generally found that variations in meaningfulness (M) are more effective when they occur on the response side than on the stimulus side (cf. Underwood and Schulz, 1960, pp. 35-42, for a review). One way of accounting for this finding is to-assume that variations of response-M can influence both the response-recall stage and the associative stage, whereas, variation of stimulus M can affect the associative stage only. This interpretation leads to the expectation that if the necessity for response-learning were eliminated, then the effect of M would be equivalent for variations on the stimulus and response side. Some evidence for this expectation was provided in an experiment by Epstein and Streib (1962). The acquisition of lists of Lo M - H i M pairs and 'turned over' Hi M-Lo M pairs was compared under three conditions. Condition A was anticipatory learning which requires both response-learning and associative learning. Under this condition List Lo-Hi was acquired in half the number of trials required for List Hi-Lo. Conditions Re and Rd were easy and difficult tests of recognition. Under these conditions response-learning was not necessary since the correct response was present at the time of testing. The rates of learning Lists Lo-Hi and Hi-Lo were identical under Condition Re, in agreement with the theoretical expectation. However, under Condition Rd, List Hi-Lo 1 Grateful acknowledgment is made to Rachel Streib for her assistance in collecting the data a n d performing the statistical analyses.
was learned twice as rapidly as List Lo-Hi, which represents a reversal of the usual finding. This latter result suggested that when response learning is equated stimulus-M exercises a powerful influence on learning. Presumably, the effect of stimulus-M could not be discerned under Condition Re because both lists were acquired very rapidly. The present experiment was a reexamination of the two-stage analysis of the relative effects of stimulus and response M with a new technique for eliminating differences in response-availability. The recognition test used in the earlier study entailed various interpretive difficulties which made it desirable to employ a different method. In addition, the present design included conditions for testing the implication derived from the result for Rd concerning the influence of stimulus M. The general plan of the main experiment was to compare the anticipatory.learning of lists of Lo-Lo, Lo-Hi, Hi-Lo, and Hi-Hi pairs when response-availability was equated for all lists. Following the lead of Underwood et al. (1959) and Asch and Ebenholtz (1962a, 1962b) response-availability was defined by the operations of free recall. In other words, if an item was produced by S on a test of free recall, then the item was considered to be available. The experiment was performed in two phases. In the first phase a series comprised of the items later to serve as responses in paired associate lists was presented. After each presentation of the list S was asked to reproduce the list orally by free recall. This 242
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was continued ufltil S successfully reproduced the entire list. I m m e d i a t e l y following the completion of this task, S commenced the anticipatory learning of a list of pairs whose responses were the items learned in free recall. I n order to assess the effect of prior response-learning, four additional groups learned the same lists without prior response-learning.
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Subjects. The Ss were 16 undergraduate summer session students at the University of Kansas. None of them had participated previously in experiments on verbal learning.
Procedure. Five high-M (mean ~-5.40) and five low-M items (mean z 1.40) were selected from the pool of items later to be used as responses in the paired-associate task of the main experiment. These items were presented serially in a memory drum at a 2-see rate. The S was instructed to learn the items for the purpose of reproducing them in free recall. The items were presented in five different random orders. The same order was not repeated on successive trials, After each presentation of the complete list S was allowed 1 rain in which to reproduce the items orally in any order he wished. The E recorded S's responses in writing and permitted S to see the record as it was being produced. The criterion of mastery was complete recall of all 10 items. Immediately following the criterial trial, the M values of the items were determined for each S. For this purpose Noble's (1952) production method was used. Every effort was made to duplicate Noble's operations exactly. The records were then scored by an independent judge who was not familiar with the M values of the items or the purpose of the experimental operations.
Results. T h e mean number of trials to total recall for the 16 Ss was 4.38 ( S D - ~ 2.25). W h e n the two types of items were considered separately, it was found t h a t the mean numbers of trials were 4.82 (SD ~ 1.35) and 4.00 ( S D - ~ 1.34) for the five high-M and five low-M items, respectively. This difference is not statistically significant. T h e d a t a for two Ss were discarded in the analysis of the results of the production method. I n s t e a d of responding to the stimulus-item these Ss persisted in "free-associating." Therefore, the post-learning M values were based on the d a t a of 14 Ss. T h e M values of all the items were somewhat higher after item-learning than before. However, the relative status of the high and low items was unaffected b y the prior learning. This l a t t e r observation was confirmed b y two statistical analyses. A t test of the difference between the high(mean z 8.37) and low-M (mean ---- 3.43) items alter learning yielded a value of 8.41 (p < .01, d] ~ 13). I n addition, a Spearman r a n k order correlation of 0.94 (p < .01) was obtained between the M values of the 10 items as given b y Noble (1952) and the M values derived from the number of associates produced b y our Ss after learning. Conclusion. N o evidence was obtained to indicate that item-learning in a free-recall situation affects the relative M values of the items. 3 There was not a single instance in which a low-M item received a higher-score than a high-M item. T h e difference between the higest of the low-M items and the lowest of the high-M items was 3.31 on Noble's list and 3.07 after item-learning. Although these findings answer the question
2 Riley and Phillips (1959) have shown that prefamiliarization does not alter relative associative values. However, their conditions were sufficiently different from ours as to make a new test desirable.
3 The absence of a differential effect of item learning on M values was also demonstrated in an unreported experiment in which different groups of Ss learned homogeneous lists of high- or low-M items.
PRELIMINARY EXPERIMENT A Prior to the main experiment a p r e l i m i n a r y s t u d y was performed to explore an i m p o r t a n t methodological question. W h a t is the effect of item-learning, under conditions of free recall, on the M values of the items? 2 I n particular we needed to know whether the relative M values of the low- and high-M response items remained intact after item-learning. I t is obvious, t h a t if item-learning resulted in uncontrolled modifications of M, then itemlearning could not be employed for the present purposes.
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for which the experiment was designed, they introduce a new interpretive difficulty which warrants comment. The experiment demonstrated that item-learning produces comparable changes of M for low- and high-M items. There is some evidence that the differences in learning associated with variations Of M depend on whether the variations are in the lower or higher range of the scale of M. However, the precise character of this relationship is still in doubt. Some studies show a tendency toward positive acceleration of rate of acquisition with increasing meaningfulness, others have shown a trend toward negative acceleration, still others have conjectured that the relationship between difficulty and M might be sigmoid (reviewed by Underwood and Schulz, 1960, Chap. 3). Nevertheless, it must be noted that if greater differences in learning are produced by variations in the lower range than by comparable scale differences in the upper range, then the changes in M produced by item-learning would reduce the difference between the acquisition rates for the lists which differ in response-M. Therefore, a potential confounding must be recognized. PRELIMINARY EXPERIMENT B An additional question which required investigation prior to the main experiment concerned the short-term retention of highand low-M items learned to the same criterion of free recall. It is generally found in serial and paired-associate learning that rate of acquisition is one of the factors which determines retention. Thus, if an easy and difficult series of items are learned to the same criterion of mastery, but at different rates, then an early test of retention will usually reveal differences between the two lists. It is generally the case that high-M items are learned more rapidly than low-M items. 4 Therefore, 4 This was not the case in Experiment A, although the direction of the difference was consistent. Perhaps the failure to find a difference is due to the fact that a mixed list was used.
despite prior response-learning the high- and low-M items may not be equally available as responses at the beginning of the pairedassociate task in the main experiment. The purpose of Experiment B was to examine this question under conditions identical to those of the main experiment. Subjects. Twenty students from the same population which provided Ss for Experiment A and the main experiment served as Ss. They were assigned alternately to two groups in the order with which they appeared for the experiment. Procedure. In order to make the procedure identical with that of the main experiment, each S began with trials on a practice list of 4 pairs of adverbs. Following this, Ss in Group Lo learned the 10 low-M items which served as responses in the Lo-Lo and Hi-Lo lists of the main experiment. Group Hi learned the 10 high-M items assigned as responses to the Lo-Hi and Hi-Hi lists of the main experiment. The procedure and criterion of mastery were the same as in Experiment A. Following the criterial trial, Ss were read the instruction for paired-associate learning given to the Ss in the main experiment. This usually entailed an interval of 2 rain. Then Ss were asked to reproduce the list of 10 items in free recall. One minute was allowed for the test. Results. The mean number of trials to mastery in free recall was 3.54 (SD z 1.63) and 10.27 (SD ~ 4.90) for Group Hi and Group Lo, respectively. This difference is highly significant (t ---~4.31, df ~ 18, p .01). The mean number recalled after the paired-associate instructions was 9.36 (SD - 0.92) and 9.09 (SD ~ 0.83) for Group Hi and Group Lo, respectively. This difference does not approach significance. Conclusion. Short-term retention of items learned under the present conditions of free recall is very high and does not differ for high- and low-M items. We conclude, therefore, that the high- and low-M items learned to the same criterion of free recall in the main experiment will be equally recallable qua items when paired-associate learning is initiated. We would also presume that the slight retention loss obtained in the present experiment would be erased by the initial presentation of the responses on the first trial
RESPONSE AVAILABILITY of t h e p a i r e d - a s s o c i a t e list. T h i s w o u l d enh a n c e t h e r e c a l l a b i l i t y of t h e r e s p o n s e - i t e m s a t t h e t i m e of t h e first t e s t t r i a l i n t h e m a i n experiment. MAIN EXPERIMENT I n t h i s e x p e r i m e n t t h e a c q u i s i t i o n of L o - L o , L o - H i , H i - L o , a n d H i - H i lists w a s c o m p a r e d with and without prior response learning. The following were the main predictions c o n c e r n i n g t h e effects of p r i o r i t e m l e a r n i n g : ( 1 ) P r i o r i t e m l e a r n i n g s h o u l d f a c i l i t a t e acq u i s i t i o n of all f o u r lists. ( 2 ) W h e n s t i m u l u s M is c o n s t a n t , p a i r s c o m p r i s e d H i M a n d L o M
responses
learning.
should
(3) When
not
differ i n
ease
of
r e s p o n s e - M is c o n s t a n t ,
pairs with Hi M stimuli should be acquired more rapidly than pairs with Lo M stimuli. ( 4 ) T h e difference in p e r f o r m a n c e for t h e p a i r s w h i c h differ in s t i m u l u s - M s h o u l d b e l o c a l i z e d in t h e a s s o c i a t i v e s t a g e of l e a r n i n g .
MaLerlals. Twenty Lo M and 20 Hi M items were selected from Noble's (1952) list. The mean values of the items were 1.43 (SD ~ 0.27) and 6.67 (SD 1.31) for the Lo M and Hi M items, respectively. These were formed into four lists of 10 pairs each. List Lol-Lo 2 consisted of pairs composed by combining the Lo M items. The mean difference between the M values of the stimuli and responses comprising each pair in List Lol-LO 2 was 0.04. List LOl-Hi 2 consisted of the same stimuli paired with Hi M responses. The mean difference between the M values of the stimuli and responses in this list was 5.28 (SD ~-1.03). List Hil-Lo 2 was comprised of the responses in List LOl-LO 2 paired with Hi M stimuli. The mean difference between the M values for the stimuli and responses was 5.25 (SD ~-1.10). List Hil-Hi 2 was composed of the stimuli used in List Hil-Lo 2 paired with the remaining 10 Hi M items. The mean difference between the M values of the stimuli and responses in List Hil-Hi 2 was 0.01. In the construction of the pairs care was exercised to avoid any obvious associational linkages. The above procedure for construction of the Lo-Hi and Hi-Lo pairs departs from the convention of using the same items on both sides, i.e., LOl-Hil, Hii-Lo 1. This procedure was abandoned in order to achieve complete identity for the variables which were held constant in the main comparisons (see second and third predictions). This is not possible with the typical procedure which counterbalances
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S and R items. In the counterbalanced design, either the equivalent-M responses must be different, or the equivalent-M stimuli must be different.
Subjects. Eighty-eight students from the same population as in the preliminary study served as Ss. The first 44 Ss were divided into blocks of 4 each in order of their appearance for the experiment. Within each block, 1 S was randomly assigned to each of the 4 experimental conditions. The next 44 Ss were assigned in the same manner to the 4 control conditions. Thus there were 8 groups of 11 Ss each.5 Procedure. Each S began with five practice trials with a list of four trisyllabic adverbs. The conventional method of anticipation was used. This practice task provided a basis for assessing initial learning ability, and also served to reduce the confusion and consequent variability which otherwise occurred when S was switched from free recall of a series to paired-associate learning. Upon completion of the practice task S learned the 10 response items of his assigned paired-associate list. The free-recall procedure employed in the preliminary studies was followed again. Learning was continued to the criterion of complete recall. Immediately following the criterial trial, S began learning the paired-associate list. The list was exposed on a memory drum at a 2."2 sec rate with a 4-see intertrial interval. Five different orders of presentation were used. None of the five orders presented the responses in an order identical to that which obtained during the prior item-learning. The S was instructed to pronounce all the items aloud and guessing was encouraged. The procedure for the four control conditions was the same as that of the experimental conditions with one important exception: there was no prior responselearning. Instead, these Ss worked on number-completion tasks. The amount of time allowed for these filler tasks was the average time required for responselearning by their respective experimental groups. Results. T h e t o t a l n u m b e r c o r r e c t for t h e l a s t t w o trials o n t h e p r a c t i c e list was d e t e r m i n e d for e a c h S. T h e m e a n s w e r e 4.36 (SD : 2 . 0 1 ) , 2.91 ( S D - ~ 1.70), 5.00 ( S D - 2 . 7 9 ) , a n d 4.09 ( S D z 2.26) for t h e i t e m l e a r n i n g g r o u p s a s s i g n e d to L i s t s L o - L o , H i Lo, L o - H i , a n d H i - H i , r e s p e c t i v e l y . T h e m e a n s w e r e 3.45 ( S D ~ 2 . 4 7 ) , 3.49 ( S D z 2 . 4 7 ) , 5 The desirability of the control conditions became apparent only alter the experiment was begun. Therefore, the atypical procedure of running the control Ss after the experimental Ss.
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4.28 (SD.~ 1.63), and 3.87 (SD = 2.28) for the groups without item-learning assigned to the corresponding lists. A 2 X 2 X 2 analysis of variance of the data for the last two trials shows that none of the main effects (item-learning, stimulus-M, response-M) or interactions are statistically significant. This indicates that the Ss in the eight groups were comparable in palred-associate learning abifity at the outset of the experiment. Next, the item-learning scores for the Lo M and Hi M items were compared. The mean number of trials was 3.32 (SD--2.01) and 7.78 (SD--4.31) for the Hi M and Lo M items, respectively. This difference is highly significant (t - - 4.41, d] ~ 42, p ~ .01), confirming the findings of Experiment B. TABLE I
MEAN NUMBER OlP TRIALS TO MASTERY W I T H A N D WlTI-IOUT PRIOR R E S P O N S E - L E A R N I N G
With prior response learning
Without prior response learning
Lists
Mean
SD
Mean
SD
Lo-Lo Lo-Hi Hi-Lo Hi-Hi
16.64 8.27 14.73 7.64
7.43 3.58 12.56 7.72
23.36 8.91 21.27 10.54
3.47 2.43 8.11 7.85
Table 1 presents the mean trials to mastery of the four paired-associate lists with and without prior response-learning. A 2 X 2 X 2 analysis of variance shows that the condition of prior training, i.e., item-learning, is a significant source of variance (F--~ 7.22, d]-1/80, p < .01). There were no significant interactions between this variable and stimulus-M or response-M. Prior item-learning facilitated acquisition independently of variations in stimulus- or response-M. Inspection of Table 1 shows that although prior item-learning reduced the differences between the lists it did not alter the relative speeds of acquisition. Neither the second nor third prediction, which were derived from the two-stage analysis, was confirmed. The analysis of variance showed that response-M was
a significant source of variance (F ~-42.16, d / - - 1 / 8 0 , p ~ .01). However, the interaction of response-M with stimulus-M did not approach significance. In addition, responseM did not interact significantly with the conditions of prior training. The facilitating effect of high response-M was independent of stimulus-M and prior item-learning. On the other hand, sfimulus-M was not a significant source of variance. Nor was there a significant interaction of stimulus-M and condition of prior learning. Thus no evidence was obtained in support of our prediction that with response-M constant, variations in stimulus-M would influence speed of acquisition. The next index of performance which was analyzed was the trial on which a response first occurred regardless of placement. This index is often taken as a measure of the first stage of associative learning (e.g., Postman, 1962). One would expect that response occurrence would be earlier following item-learning, and that prior item-learning would eliminate the differences between Hi M and Lo M responses in this regard. Table 2 presents the means for the trials to initial response occurrence for the four lists under both conditions of training. The training variable proved to be a significant source of variance (F z !7.55, d] z 1/80, p < .01). Prior item-learning produced earlier response occurrence. The effect of response-M was also significant (F ~ 45.91, d ] z 1/80, p ~ .01). The Hi M responses occurred earlier than the Lo M responses. In addition, there was a significant interaction of response-M with condition of prior training (F ~ 5.43, 1/80, p ~ .05). Inspection of Table 2 shows that the difference between the Ix) M and Hi M responses was smaller when item-learning preceded the associative task. Duncan's new multiple range test with a .05 was used to make individual comparisons among the four relevant means (Edwards, 1960, pp. 136-140). Four of the six differences were significant. The mean for the group
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RESPONSE AVAILABILITY TABLE 2 MEAN TRIALS TO INITIAL OCCURRENCE OF RESPONSE AND MEAN DIFFERENCE BETWEEN TRIAL O1~ INITIAL RESPONSE OCCURRENCE AND TRIAL OF FroST CORRECT PAIRING
Differencebetween initial response occurrenceand first correct pairing
Trials to initial response occurrence
Lists Lo-L o Lo-Hi Hi-Lo Hi-Hi
Item learning Mean SD 4.43 2.73 3.83 2.14
1.37 1.02 2.44 2.14
No item learning Mean SD 7.35 3.47 5.87 2.81
which learned pairs containing Lo M responses without prior item-learning was significantly greater than each of the other means. The mean for the group which learned the pairs containing Lo M responses after item-learning was significantly greater than the mean for the group which received Hi M responses after item-learning. Therefore, while the difference between the initial occurrence of Hi M and Lo M responses was reduced by prior item-learning, Hi M responses continued to occur significantly earlier. Also, contrary to expectation, stimulus-M was a significant source of variance (F - - 4.78, d] -~- 1/80, p < .05). On the average, high stimulus-M yielded earlier response-occurrence. There were no significant interactions between stimulus-M and the other variables. Table 2 also shows the mean difference between trial of initial response occurrence and the first correct pairing. This difference provides an estimate of the length of the associative stage. The analysis of variance of these data showed only one significant main effect and no significant interactions. Neither stimulus-M nor the conditions of prior training had a significant effect on the difference scores. Only response-M remained a significant variable (F--- 12.91, d]~- 1/80, p < .01). The differences between the trial of initial response occurrence and first correct pairing were smaller for the pairs containing the Hi M
1.97 0.93 3.20 0.84
Item learning Mean SD 0.99 0.42 1.66 0.31
0.86 0.45 1.58 0.62
No item learning Mean SD 0.76 0.37 1.75 0.46
0.65 0.34 1.56 0.38
responses. This finding does not conform to the prediction derived from the two-stage theory. Several auxiliary comparisons are also relevant to the theoretical interpretation under examination. These involve comparisons between lists containing responses of different M value when learned with and without prior item-learning. Does item-learning facilitate the lists containing Lo M responses so that they are acquired as rapidly as the lists containing Hi M responses but without prior item-learning? For this purpose List Lo-Lo and list Hi-Lo preceded by item learning can be compared with List Lo-Hi and List Hi-Hi, respectively, without prior item-learning. An inspection of Tables 1 and 2 shows a general tendency in favor of Lists Lo-Hi and List HiHi. Thus, despite the fact that the Lo M response items were made highly available by recent item-learning the superiority of high response M was not eliminated. DISCUSSION
The results of the main experiment provided general support for the two-stage analysis of associative learning. This conclusion is supported by the finding that prior item-learning facilitated acquisition of pairs containing these items as responses. This support needs to be qualified due to the absence of a basis for comparing the response-learning condition
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with a stimulus-learning and an irrelevant item-learning condition. The force of this qualification is mitigated somewhat by the fact that item-learning did not affect all of the performance measures. Item-learning facilitated overall mastery mainly by producing earlier response-occurrence. It did not significantly affect the speed with which the response was correctly associated with the stimulus. Thus, the effect of item-learning was observed in the response-learning stage only, in agreement with the implications of the two-stage theory. The experimental findings did not support the two-stage analysis as it applies to the influence of M on associative learning. However, in view of the demonstrated usefulness of this analysis in relation to other questions, it will be prudent to reexamine the present study before reaching a final conclusion. The basic premise of the experimental rationale was that high- and low-M items which initially differed in availability could be equated in this regard by prior item-learning. In retrospect, there are two arguments which can be raised concerning this premise. First, it is possible that availability in free recall does not guarantee response recall under conditions of paced anticipation. In the former case, S is set to produce items qua items. In the latter situation, S is set to produce responses in their prescribed place, and in a temporal order governed by the order of stimulus presentation. A second argument might be that the nonsense disyllables which served as the Lo M items could not have been expected to become equal in availability to the real words which served as the Hi M items. In support of these arguments is the finding that, despite prior item learning, Hi M items occurred as responses earlier than Lo M items. An experiment to remedy these possible shortcomings would include the following features: (1) item availability would be produced under conditions in which the items functioned as responses to stimuli; (2) none of the items would be real words; and (3) re-
sponse availability would be checked at various stages during the learning of the critical list of pairs. In addition to their bearing on the question of M and associative learning the present findings may have implications for the general two stage-analysis. In particular, the data on initial response occurrence suggest that there may be variables other than item recallability which can determine the speed with which an item occurs as a response somewhere in the list of pairs. In other words, response occurrence may not be a valid indicator of the termination of the first stage. Response learn•ng may occur without response performance. This would tend to limit the usefulness of the two-stage distinction in the analysis of data. SUIVflVfARY
The main purpose of this study was to examine the effects of stimulus-M and response-M on paired-associate learning when the low- and high-M responses are made equally ~/vailable. The procedure for equating response availability consisted of learning the response items in random serial order to a criterion of complete free recall. Immediately following the criterial trial, S learned a list of paired associates by the method of anticipation. Preliminary Experiments A and B were concerned with some basic effects of itemlearning. The results of Experiment A showed that item-learning under conditions of free recall does not affect the relative M values of low- and high-M items. Experiment B showed that low- and high-M items are equally available in short-term retention despite the fact that low-M items are acquired in free-recall learning at a much slower rate than high-M items. The main experiment compared the acquisition of Lo-Lo, Lo-Hi, Hi-Lo and Hi-Hi lists with and without prior response-learning. A different group of 11 Ss was assigned to each of the eight conditions. These main predictions concerning the effects of prior item-
RESPONSE AVAILABILITY learning were derived from the two-stage analysis of associative learning: (1) prior item learning should facilitate acquisition of all four lists; (2) when stimulus-M is constant, pairs comprised of Hi M and Lo M responses should not differ in ease of learning; (3) when response-M is constant, pairs with Hi M stimuli should be acquired more rapidly than pairs with Lo M stimuli; (4) the difference in performance for the pairs which differ in stimulus M should be localized in the associative stage of learning. Analyses were performed of the trials to criterion, trials to first response occurrence regardless of placement, and the difference between the trial of initial response occurrence and first correct pairing. Only the first prediction given above was supported. The results were discussed as they relate to the two-stage analysis of associative learning. REFERENCES
ASCII, S. E., AND EBENIIOLTZ, S. M. The principle of associative symmetry. Proc. Amer. Philo. Soc.,
1962, 106, 135-163.
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Ascii, S. E., AND EBENHOLTZ, S. IVY.The process of free recall: Evidence for nonassociative factors in acquisition and retention. J. Psychol., 1962, 54, 3-31. EDWARDS,A. L. Experimental design in psychological research. New York: Rinehart, 1960. EPSTEIN, W., AND STREIB, R. The effect of stimulus meaningfulness and response meaningfulness in the absence of response learning. J. verb. Learn. verb. Behavior, 1962, 1, 105-108. NOBLE, C. E. An analysis of meaning. Psychol. Rev., 1952, 59, 421-430. POSTMAN, L. The temporal course of proactive inhibition for serial position. J. exp. Psychol., 1962, 63, 361-369. RILEy, D. A., AND PIIILLIPS, L. W. The effects of syllable familiarization on rote learning, association value, and reminiscence. J. exp. Psychol., 1959, 57, 372-379. UNDERWOOD, B. J., RUNDQUIST, W. R., AND SCHUIaZ, R. W. Response learning in paired-associate lists as a function of intralist similarity. J. exp. Psychol., 1959, 58, 70-78. UNDERWOOD, B. J., AND SCHIYLZ, R. W. Meaningfulness and verbal learning. Philadelphia: Lippincott, 1960. (Received December 26, 1962)