Verbal Discrimination Learning Research Articles

Individual differences in the functional neuroanatomy of verbal discrimination learning revealed by positron emission tomography

Why do some people have better memory abilities than others? This issue has been of long-standing interest to scientists and lay people. However, using purely behavioral methods, psychologists have made little progress in illuminating it. Now that functional brain imaging techniques have become available to study mind/brain relations, there is a new promise of understanding individual differences in learning and memory in terms of corresponding differences in brain activity. In this paper, we will present a positron emission tomography (PET) study designed to examine individual differences in learning and memory abilities. The basic assumption is that different patterns of brain activity serve as strong predictors of memory performance. Two specific questions were addressed in this study: (i) Can PET illuminate the relations between memory processes and their neuroanatomical correlates among individual learners and rememberers? and (ii) if so, how are these relations affected by the stage of practice on a given memory task? Our PET study examined individual differences in the neuroanatomical correlates of multi-trial verbal discrimination learning in 16 young healthy subjects. The results identified patterns of brain regions in which blood flow correlated with subjects' retrieval performance. However, these regions did not correlate with performance during all learning trials. Instead, a gradual shift was observed from one pattern of brain regions to another over the course of learning. These results suggest that individual differences in memory performance are related to differences in neural activity within specific brain circuits.

The identity model and factors controlling the superiority of the study-test method over the anticipation method.

Short-term memory (STM) and long-term memory (LTM) components are assumed to overlap in such a way that the response reflects predominantly STM components in short retention intervals but LTM ones in long retention intervals. Based on the STM and LTM overlap hypothesis, the identity model postulates that basic processes per study, test, and intervening study and test events as well as intercycle intervals, respectively, are the same for both anticipation and study-test methods in cued (paired-associate) recall and recognition (verbal discrimination learning). A crucial difference between the two methods is the differential retention interval distribution (containing an overlap area). Amounts of STM components in the short-term store (STS), that is, critical items, seem to control the varied superiority of the study-test method over the anticipation method. This is directly linked to the learning difficulty dimension, which in turn is determined by such variables as list length, learning materials, exposure durations (presentation rates), acquisition stages, learning ability, developmental stages (ages), and others.

Feedback and anxiety in verbal discrimination learning.

120 volunteers learned a 12-pair list of 4-letter words of low frequency. The independent variable was feedback (positive only, negative only, or positive and negative), and trait anxiety (high or low) and sex (male or female) were used as subject-variables. For errors per trial, the interaction of feedback, anxiety, and trials was significant. Individuals low in anxiety performed poorly when exposed to negative feedback while feedback contingencies were not related to performance differences for the highly anxious individuals. The results are discussed in terms of task-related state anxiety.

Luck and learning: feedback contingencies and initial success in verbal discrimination learning.

Ninety undergraduate volunteers learned a 12-pair, low frequency, verbal discrimination list. The independent variables were feedback (positive only, negative only, or both) and initial success (17%, 50%, or 83% correct on trial one). With the total errors on nine trials as the dependent variable, the main effect of feedback was found to be not significant. The main effect of initial success was significant. Subjects who started at 50% correct had the most difficulty learning the list and subjects in the 83% correct condition learned quickest. The predicted interaction between feedback and initial success was not significant, even though the means for the three types of feedback at the 17% correct starting level reflect the expected differences. The results are interpreted as supporting the rule-use component of frequency theory. The relationship between initial success and subsequent performance appears to be curvilinear, rather than linear, as many theorists have assumed.

The Generality of the Retention Interval Model.

Elaborations and refinements were made for core constructs of the retention interval (RI) model that specified a major difference between anticipation and study-test methods to be short-term memory (STM) processes in differential retention intervals. Subsequent developments reinforce the model and suggest that basic processes per each type of event are, respectively, the same for both methods (except for quantitatively differential retention intervals)-the identity hypothesis. The RI model unveiled another major factor, learning difficulty, that controls performance differences between the two methods. By encompassing new developments, the generality of the RI model was tested in a variety of situations. The model seems to hold firmly for a wide range of paired-associate and verbal discrimination learning paradigms including such cross-variations as the following: mixed vs. unmixed list design, constant vs. random item presentation orders, forward vs. backward associations, part vs. whole list designs, and visual vs. auditory modalities. Other theories, in contrast, seem to lack mechanisms to cope with inconsistent data, prevalent throughout the vast scope of learning situations.

Rates of Presentation, Displaced Rehearsal, and Verbal Discrimination Learning

Four experiments were conducted to test the notion that rehearsal in a verbal discrimination learning task is not confined to the feedback interval, i.e., displaced rehearsal. Specifically, it was hypothesized that during early learning trials rehearsal would be restricted to the feedback interval. However, during later trials, once the subject was beyond the point of guessing the correct item, rehearsal could also occur during the anticipation interval. In all four experiments the opportunity for rehearsal was manipulated by presenting factorial combinations of either short or long anticipation and feedback intervals. Contrary to the hypothesis, no consistent differences were noted across trial blocks. However, the evidence did indicate that a long anticipation interval combined with a short feedback interval facilitated learning relative to a short anticipation interval combined with a long feedback interval. A modified version of displaced rehearsal provides a reasonable explanation for this finding if it is assumed that correct recognition is not a prerequisite for displaced rehearsal.

Feedback and Instructions in Verbal Discrimination Learning

120 volunteers learned a 12-pair, low-frequency verbal-discrimination list. The independent variables were feedback (positive only, negative only or continuous), task instructions (informed or uninformed regarding the nature of the task), and feedback instructions (informed or uninformed regarding the type of feedback). Using the total errors to criterion as the dependent variable, the results were analyzed using a 3 × 2 × 2 analysis of variance. The main effect of task feedback was significant. Subjects who received detailed instructions learned the list quicker than those who were given discovery instructions. The main effects of feedback and task instructions were not significant. None of the interactions were significant. The failure to find an interaction between feedback and instructions suggests that feedback contingencies produce differences in performance only for select populations.

Transfer as a function of shifts in task difficulty in verbal discrimination learning

This study investigated the relationship between transfer of training and shift in task difficulty for verbal discrimination learning. Also, it attempted to determine whether there are any differences in the tendency to make persistent errors in the two transfer conditions. Task difficulty was manipulated by varying the number of word alternatives, with either two words (easy task) or four words (hard task) in each word presentation set. Two lists, each with 26 sets of words, were presented for five trials. Each word set was shown for 1 sec, followed by 3 sec for response and 1 sec for feedback. A positive transfer effect in the hard-easy shift and a tendency toward negative transfer in the easy-hard shift were found.

Interactions among performance, task, and gender variables in verbal discrimination learning

High school students in four classes were given verbal materials of varying levels of organization in a verbal discrimination experiment. They performed (selected one of four words in each set) on half of the items and were given answers (informed) on the other half. As in two similar recent experiments, correct performed items were acquired more rapidly than correct informed items, but there was no interaction between level of task difficulty and performance. Analysis of incorrectly recalled words yielded some interesting interactions, notably the greater incorrect recall of performed responses by male students.

The stubborn-error effect in verbal discrimination learning

The stubborn-error effect (SEE), a tendency toward increasing probability of repetition of specific errors over successive trials, has been reported in tasks using verbal learning materials. The present experiment was primarily designed to investigate the time of stimulus presentation and feedback as determinants of the SEE. Verbal discrimination learning data collected from 80 introductory psychology students confirmed the SEE in a large number of subjects. Its dependence upon temporal factors, most notably the time of stimulus presentation, was also demonstrated. The present data did not support the earlier finding of a gender difference (males more likely than females to contribute to the effect). Finally, the subjects who did show some SEE were found to be generally less capable, as measured on a variety of independently obtained indicators of academic achievement.

Verbal discrimination learning and retention as a function of performance or observation and ease of conceptualization of task materials

Four classes of high school psychology students were given verbal discrimination learning tasks with correct responses of varying ease of conceptualization. Study trials were administered with subjects working in pairs, with each subject alternately performing (selecting one of the two projected words) and observing (watching partner make selection). Both in acquisition and in 24-h free recall tests, more correct responses were made under the performance condition. Also, in each instance, there was a reliable Perform/Observe by Group (task) interaction. These results are interpreted as offering support for the proposition that reward functions, presumably operating more directly in the perform than in the observe condition, have some strengthening effect on responses that cannot be accounted for in terms of strictly cognitive processes.

Verbal discrimination learning and retention as a function of task and performance or observation

Learning and retention of verbal materials were compared in high school students under perform (guessing with feedback) or observe (watching the performer) conditions. The correct response was randomly determined, or the shortest word, or the word that made a short message when linked to contiguous correct words. In acquisition, subjects did better when performing, females did better than males, and the shortest word group did better than the other groups. There was a variety of interactions in the retention tests, for example, that between scoring (observing subjects either scored their paired performers’ responses as right or wrong or simply observed their paired performers) and trials. A transitory inhibitory effect could be attributed to the scoring operation, thus partially confirming a result reported earlier.

Verbal Discrimination Learning: Effects of Method of Presentation, Practice Distribution, and Learning Material

Summary Given both similarities and differences between recognition memory in verbal discrimination learning (VDL) and recall memory in paired-associate learning (PAL), the applicability of the retention interval model (12) formulated in PAL to VDL was examined in three experiments using nonsense syllables, two-digit numbers, and words, under both anticipation and study-test methods, with massed practice, as well as with spaced practice. A total of 240 male and female university students participated as Ss. At least partial applicability of the retention interval model to VDL situations was evident, since in line with the expectations from the theory, the superiority of the study-test method over the anticipation method was sometimes large (Experiment 3), but small at other times (Experiments 1 and 2). Through detailed analyses of sublist performances, overall retroactive interferences on which the model is based controlled VDL performances to a major extent. The proactive interferences were inconsequenti...

Single-item recognition following verbal discrimination study and/or test trials.

This experiment assessed further single-item recognition following verbal discrimination learning by varying the number of study and test trials presented during the initial verbal discrimination task. Two study periods (1 and 2 study trials) and three test periods (0, 1, and 2 trials) were factorially combined to yield six experimental groups. Increasing the test periods increased recognition of the prior words to be verbally discriminated as old items. Although subjects could identify the prior function of the old items, the variables did not increase or decrease this ability.

Phenomenal Frequency Effects in Verbal-Discrimination Learning: Resolving a Discrepancy

The present study was conducted to assess one possible explanation for the failure of a recent experiment to uncover an effect of subjective (phenomenal) frequency in verbal-discrimination learning. It was hypothesized that the effect is more likely to emerge with words representing relatively low values of objective background frequency, where variations in phenomenal background frequency are presumably greater. Consistent with the hypothesis, college students discriminated objectively-low-frequency pairs of abstract words better when the phenomenal frequency was low than when it was high; whereas for objectively-high-frequency pairs, no phenomenal frequency effect was obtained.

An Examination of the Rule-Use Construct of the Frequency Theory of Verbal Discrimination Learning

Summary Sixty-six female and 18 male college students were employed in a study of the relative effect of instructional set and item familiarity on performance in a 20-word pair, verbal discrimination task. Results indicated performance was facilitated with a 2:1 frequency ratio of correct to incorrect items (p < .001), but the instructions and interaction effects were nonsignificant. The results were discussed in terms of overt and covert rehearsal of word pairs.

The imagery effect and phenomenal background frequency in verbal discrimination learning

A series of four experiments was conducted to assess the role of phenomenal background frequency in verbal discrimination learning and its possible involvement in the imagery effect. The initial two experiments produced a reliable imagery effect for mixed and unmixed lists with respect to concreteness of pair members, regardless of phenomenal frequency manipula­ tions, with words high in objective background frequency. No effects were found for phenomenal background frequency. Experiment 3 involved phenomenal frequency ratings for 200 abstract and 200 concrete words. Experiment 4 evaluated the role of phenomenal background frequency for a mixed list using words low in objective frequency. A reliable imagery effect was again found with no effects for phenomenal frequency. An alternative hypothesis involving differen­ tial accrual of situational frequency to abstract and concrete items during verbal discrimination learning to explain the imagery effect was also tested by Experiment 4 but was not supported by the data. A rather consistent finding reported in the verbal discrimination learning (VOL) literature in recent years is the easier learning of concrete (or high-imagery) word pairs relative to abstract (or low-imagery) pairs in mixed or unmixed lists (Paivio & Rowe, 1970, 1971; Rowe & Paivio, 1971, 1972; Ullrich & Balogh, 1972). This finding has proven somewhat distressing for frequency theory (Ekstrand, Wallace, & Underwood, 1966; Wallace, 1972), which has thus far served well as the major theory of VOL, since the effect is neither predicted nor readily interpretable, in any obvious way, by the theory as it currently stands. The reliability of the effect would seem to demand a search for an interpretation that could be accommodated by frequency theory or a considerable revision of the theory if it is to survive without substantial limitations. A recent report by Ghatala and Levin (1976) has suggested that the imagery effect may be due to an apparent confound of phenomenal background frequency with concrete and abstract items in such a way that the effect may be interpretable by appeal to the Weber's law postulate found in frequency theory. Should such be the case, the search for a viable frequency theory explanation would be ended and the theory would escape serious revision. Thus, a major purpose of the present investigation was a systematic assessment of this possibility.

The Relative Effectiveness of Rules 1 and 2 in Verbal Discrimination Learning

The prediction, derived from frequency theory, that performance on a verbal discrimination task would be the same for Rules 1 and 2 was tested. Appropriateness of the rules was achieved by varying the number of times the right (R) and wrong (W) items were pronounced during the feedback interval. The sequence of pronunciation (R-W or W-R) was also manipulated in order to determine whether rehearsal depends on the order of pronunciation. After the task was completed, each subject was given a modified free-recall task to investigate possible relationships between the various treatment conditions and incidental learning. Analyses of the data revealed a significant differential pronunciation effect (p < .05) indicating that Rule 2 responding retarded acquisition rate. Superior performance on the modified free-recall task was associated with a W-R, relative to an R-W, sequence of pronunciation during feedback. Discussion of the results indicated possible explanations inconsistent with frequency theory predictions.

False Recognition of Synonyms of Right and Wrong Items in Multiple-Item Recognition Learning

The hypothesis that right items are processed at a featurally deeper level than wrong items was tested. After one, two, or four study trials on a list of paired right and wrong items, subjects were asked to decide whether individual items, including new ones that were synonyms of the prior ones or unrelated to them, were old or new and, if old, had been right or wrong. A false-recognition effect was found for synonyms of both right and wrong items, suggesting that wrong items, as well as right, are processed at a semantic level. However, that effect took more study trials to appear for synonyms of wrong items, reflecting the disparity between right and wrong items in the rates at which their features accrue frequency units. Implicit in Ekstrand, Wallace, and Underwood's (1966) frequency theory of verbal-discrimination learning - that is to say, multiple-item recognition learning - is the assumption that the processing of right items does not differ qualitatively from the processing of wrong items. Processing consists of representational and/or rehearsal responses to items whether they function as right or wrong in the pairs. That is, the processing of right items is distinguishable from the processing of wrong items only in terms of the greater number of responses elicited by right items. It is intuitively ap

Developmental trends in item recognition following a verbal discrimination study trial

Age-related changes in the processes mediating verbal discrimination learning were investigated by a procedure in which right, wrong, and new items were tested individually for oldness after a single study trial on right-wrong pairs. Sixth-grade children displayed higher hit rates than fourth-grade children for both right and wrong items, suggesting that increasing age is accompanied by both increasing rehearsal responses to right items and increasing perceptual responses to wrong items. The increase with age in responses to wrong items serves to compensate for the gain in responses to right items, thus accounting for the absence of pronounced age increments in verbal discrimination learning proficiency.