Recognition vs. classification of ill-defined category exemplars

In Experiment 1, subjects were trained on three ill-defined categories represented by 4, 8, and 12 exemplars. Learning was followed by either a classification test on old, new, and random exemplars or a recognition test in which each learning exemplar was presented with two foils, both equidistant to the learning exemplar, but one more similar to the category prototype than the other. In Experiment 2, category size was manipulated between subjects, followed by the recognition test. Recognition data indicated that increasing the number of learning exemplars did not increase the total amount of exemplar information retained for each category. In addition, the more prototypical foil was incorrectly recognized more often than the less prototypical foil. Classification data replicated previous findings that increasing category size in learning enhances classification of new exemplars. The results were interpreted in terms of the relative amounts of categorical and idiosyncratic information that were retained from the original learning stimuli. It was proposed that categorical information can become a more dominant determinant of performance as category size increases.     

The modulating influence of category size on the classification of exception patterns

Generalization gradients to exception patterns and the category prototype were investigated in two experiments. In Experiment 1, participants first learned categories of large size that contained a single exception pattern, followed by a transfer test containing new instances that had a manipulated similarity relationship to the exception or a nonexception training pattern as well as distortions of the prototype. The results demonstrated transfer gradients tracked the prototype category rather than the feedback category of the exception category. In Experiment 2, transfer performance was investigated for categories varying in size (5, 10, 20), partially crossed with the number of exception patterns (1, 2, 4). Here, the generalization gradients tracked the feedback category of the training instance when category size was small but tracked the prototype category when category size was large. The benefits of increased category size still emerged, even with proportionality of exception patterns held constant. These, and other outcomes, were consistent with a mixed model of classification, in which exemplar influences were dominant with small-sized categories and/or high error rates, and prototype influences were dominant with larger sized categories.     

The modulating influence of category size on the classification of exception patterns

Generalization gradients to exception patterns and the category prototype were investigated in two experiments. In Experiment 1, participants first learned categories of large size that contained a single exception pattern, followed by a transfer test containing new instances that had a manipulated similarity relationship to the exception or a nonexception training pattern as well as distortions of the prototype. The results demonstrated transfer gradients tracked the prototype category rather than the feedback category of the exception category. In Experiment 2, transfer performance was investigated for categories varying in size (5, 10, 20), partially crossed with the number of exception patterns (1, 2, 4). Here, the generalization gradients tracked the feedback category of the training instance when category size was small but tracked the prototype category when category size was large. The benefits of increased category size still emerged, even with proportionality of exception patterns held constant. These, and other outcomes, were consistent with a mixed model of classification, in which exemplar influences were dominant with small-sized categories and/or high error rates, and prototype influences were dominant with larger sized categories.     

Regulating recognition decisions through incremental reinforcement learning

Does incremental reinforcement learning influence recognition memory judgments? We examined this question by subtly altering the relative validity or availability of feedback in order to differentially reinforce old or new recognition judgments. Experiment 1 probabilistically and incorrectly indicated that either misses or false alarms were correct in the context of feedback that was otherwise accurate. Experiment 2 selectively withheld feedback for either misses or false alarms in the context of feedback that was otherwise present. Both manipulations caused prominent shifts of recognition memory decision criteria that remained for considerable periods even after feedback had been altogether removed. Overall, these data demonstrate that incremental reinforcement-learning mechanisms influence the degree of caution subjects exercise when evaluating explicit memories.     

Haptic concepts in the blind

We investigated and compared the acquisition of haptic concepts by the blind with the acquisition of haptic concepts by sighted controls. Each subject—blind, sighted but blindfolded, sighted and touching, and sighted only-initially classified eight objects into two categories using a study/test format, followed by a recognition/classification test involving old, new, and prototype forms. Each object varied along the dimensions of shape, size, and texture, with each dimension having five values. The categories were linearly separable in three dimensions, but no single dimension permitted 100% accurate classification. The results revealed that blind subjects learned the categories quickly and comparably with sighted controls. On the classification test, all groups performed equivalently, with the category prototype classified more accurately than the old or new stimuli. The blind subjects differed from the other subjects on the recognition test in two ways: They were least likely to false alarm to novel patterns that belonged to the category but most likely to false alarm to the category prototype, which they falsely called “old” 100% of the time. We discuss these results in terms of current views of categorization.     

Category representation for classification and feature inference

This research's purpose was to contrast the representations resulting from learning of the same categories by either classifying instances or inferring instance features. Prior inference learning research, particularly T. Yamauchi and A. B. Markman (1998), has suggested that feature inference learning fosters prototype representation, whereas classification learning encourages exemplar representation. Experiment 1 supported this hypothesis. Averaged and individual participant data from transfer after inference training were better fit by a prototype than by an exemplar model. However, Experiment 2, with contrasting inference learning conditions, indicated that the prototype model was mimicking a set of label-based bidirectional rules, as determined by the inference learning task demands in Experiment 1. Only the set of rules model accounted for all the inference learning conditions in these experiments.     

Typicality in logically defined categories: Exemplar-similarity versus rule instantiation

A rule-instantiation model and a similarity-to-exemplars model were contrasted in terms of their predictions of typicality judgments and speeded classifications for members of logically defined categories. In Experiment 1, subjects learned a unidimensional rule based on the size of objects. It was assumed that items that maximally instantiated the rule were those farthest from the category boundary that separated small and large stimuli. In Experiment 2, subjects learned a disjunctive rule of the form "x or y or both". It was assumed that items that maximally instantiated the rule were those with both positive values (x and y). In both experiments, the frequency with which different exemplars were presented during classification learning was manipulated across conditions. These frequency manipulations exerted a major impact on subjects' postacquisition goodness-of-example judgments, and they also influenced reaction times in a speeded classification task. The results could not be predicted solely on the basis of the degree to which the rules were instantiated. The goodness judgments were predicted fairly well by a mixed exemplar model involving both relative-similarity and absolute-similarity components. It was concluded that even for logically defined concepts, stored exemplars may form a major component of the category representation.     

Memory and the experience of duration in retrospect

Two experiments investigated the relationship between long-term memory for events occurring during an interval and the experience of duration of the interval in retrospect. In both, Ss attended to a sequence consisting of a standard, an experimental, and a second standard interval. Then unexpected comparative duration and memory judgments were requested. In Experiment I, either 30 or 60 unrelated words occurred during the 180-see experimental interval. When more words had occurred, judgments of duration of the experimental interval, judgments of number of words presented, and number of words recognized all increased, but free recall of words was unaffected. In Experiment II, 80 categorized words occurred during the 160-see experimental interval, with category instances in either blocked or random order. When words were blocked by category, judgments of duration of the experimental interval, free recall, and recognition all increased, but judgments of number of words were unaffected. Results were discussed in terms of Ornstein’s (1969) “storage size” hypothesis.     

加工水平对普通话与粤语记忆语言依赖效应的影响

通过两个实验,考察了加工水平对普通话和粤语记忆语言依赖效应的影响。实验1考察了在有意学习中的记忆语言依赖效应。结果表明,测验的语言环境对再认有重要影响。被试在粤语测验环境下对学习过的韩国语词再认反应时短,误报率却低,辨别力强,“记得”反应占优势。实验2考察了无意学习中的记忆语言依赖效应。结果表明,被试在粤语测验环境下,对评定过的韩国语词再认反应时短,误报率却高,辨别力差,但“记得”反应占优势;但在普通话测验环境下,对评定过的韩国语词再认反应时长,误报率却低,辨别力强,“知道”和“猜测”反应增加。整个研究表明,记忆的语言依赖效应在有意学习和无意学习中都存在,但有不同的趋势,表明加工水平是影响普通话和粤语记忆语言依赖效应的重要变量     

Typicality and familiarity of faces

We examined context-free familiarity information as a source of the effects of face typicality upon face recognition. Experiment 1 tested memory for typical and unusual faces by (1) subjects who received an input list followed immediately by a recognition test (standard condition), (2) subjects who viewed all test faces (targets and lures) prior to the input list (prefamiliarization condition), and (3) subjects who viewed all test faces after the input list but prior to recognition (postfamiliarization condition). Although false-alarm errors in the standard condition were lower for unusual than for typical faces, this effect was reduced by postfamiliarization and was eliminated entirely by prefamiliarization. The prefamiliarization and typicality effects were replicated in Experiment 2, which showed that patterns of old judgments were compatible with the hypothesis that, although familiarity of new faces is greater if these faces are typical, the increment in familiarity that results from presentation is greater if these faces are unusual.     

Effects of processing fluency on comparative performance judgments

Research has shown that performance predictions are biased by the impact of processing fluency. However, existing data are inconclusive with regard to comparative judgments of performance. In five experiments, participants in an easy condition gave more favorable comparative judgments than participants in a difficult condition. Participants judged their performance more favorably if they named colors of non-color words rather than non-matching color words (Experiment 1), if they had to generate six words of a category rather than 12 words (Experiment 2), if they had to run in place for 15 s rather than 2 min (Experiment 3), but the latter result holds only true if participants were not active in sports (Experiment 4). When 67% of the items in a recognition test were old words, participants thought that their recognition performance was better than when 33% of the items were old words, although recognition performance did not differ between groups (Experiment 5). We discuss this result in the light of recent theories about effects of processing fluency on judgments.     

Bogus concerns about the false prototype enhancement effect

Two experiments addressed the mechanism responsible for the false prototype effect, the phenomenon in which a prototype gradient can be obtained in the absence of learning. Previous demonstrations of this effect have occurred solely in a single-category paradigm in which transfer patterns are assigned or not to the learning category. We tested the hypothesis that any extraneous variable potentially responsible for this effect, such as compactness varying with pattern distortion (Zaki & Nosofsky, 2004), may be functional in the single-category paradigm but not when multiple categories are available at the time of transfer. In the present study, subjects received a bogus or a real category learning phase, followed by a transfer test that required assignment into 1 or 3 prototype categories. The results showed that a minimal prototype gradient was obtained in the bogus conditions, with performance approaching chance levels when classification into 3 categories was required. In contrast, a substantial prototype gradient effect was found following learning. We conclude that the prototype gradient typically obtained following multiple-category learning is primarily driven by real learning and that the false prototype effect is itself an artifact of the single-category paradigm.     

The retrieval practice effect in associative recognition

Recalling an item interferes with recall of related memories. Evidence is presented that retrieval interference occurs in associative recognition as well as recall. In Experiment 1, subjects studied pairs of category exemplars. Retrieval practice followed, during which some pairs appeared in a cued recall test. A final test of associative recognition (with remember-know judgments) found lower accuracy and hit rate for nonpracticed pairs belonging to retrieval-practiced categories. In Experiment 2, subjects studied noun pairs from overlapping sets, with study duration manipulated between subjects. Retrieval practice was manipulated by presenting some members of a set in a previous block during the recognition test. With long study duration, retrieval interference was evident in both recognition and remember judgments. With short study duration, it appeared only in remember judgments. These results support a dual-process account in which retrieval interference is specific to recollection and becomes evident in recognition performance only when recollection is sufficiently dominant.     

Learning nonlinearly separable categories by inference and classification

Previous research suggests that learning categories by classifying new instances highlights information that is useful for discriminating between categories. In contrast, learning categories by making predictive inferences focuses learners on an abstract summary of each category (e.g., the prototype). To test this characterization of classification and inference learning further, the authors evaluated the two learning procedures with nonlinearly separable categories. In contrast to previous research involving cohesive, linearly separable categories, the authors found that it is more difficult to learn nonlinearly separable categories by making inferences about features than it is to learn them by classifying instances. This finding reflects that the prototype of a nonlinearly separable category does not provide a good summary of the category members. The results from this study suggest that having a cohesive category structure is more important for inference than it is for classification.     

Memorability judgments for high- and low-frequency words

Five experiments were conducted in order to examine subjects’ judgments of the memorability of high- (HF) and low-frequency (LF) words in the context of a recognition memory task. In Experiment 1, the subjects were provided study/test experience with a list of HF and LF words prior to making memorability judgments for a new list of HF and LF items. The findings were consistent with previous evidence (Greene & Thapar, 1994; Wixted, 1992) suggesting that subjects are not explicitly aware of the greater recognition memorability of LF words. Experiments 2–5 embedded the memorability judgment task within the recognition test itself. In these experiments, the subjects consistently gave higher memorability ratings to LF items. The contrast between the pattern of results found when the subjects made their judgments at the time of list presentation (Experiment 1) and that when they made their judgments during the recognition test (Experiments 2–5) is consistent with recent evidence that even seemingly highly related metamnemonic judgments (e.g., ease of learning judgments vs. judgments of learning for the same items) may be based on very different factors if they occur at different points in the study/test cycle. The present findings are also consistent with the possibility that very rapid retrieval of memorability information for HF and LF words may affect recognition decisions and may contribute to the recognition memory word frequency effect.     

A fuzzy trace analysis of categorical inferences and instantial associations as a function of retention interval

Two experiments on children's inferences and associative memory provided a test of predictions from fuzzy-trace theory. Specifically, it was expected that gist-based false recognitions would increase with age and that false recognitions would be uncorrelated with verbatim memory. In Experiment 1, children in Grades 1 through 5 heard lists of category labels, clustered instances from categories, and individual instances. On an immediate test, children indicated whether or not they had previously heard a series of individually presented test words. This list consisted of old words, new words, or words that were categorically or semantically related to the studied word clusters. Children made more false recognition errors for instances than for categories. Verbatim memory and inferences were unrelated. In Experiment 2, the effect of a test delay on categorical inferences and associated instances was examined with children in Grades 1 to 6. With delay, false recognition of associated instances declined for children at all grade levels. In contrast, categorical inferences increased with delay for older children. Verbatim memory and inferences were uncorrelated under immediate and 1-day delay conditions, but there were some low but significant correlations across grades under the 7-day delay. The results of the two experiments are interpreted as supporting fuzzy-trace theory.     

The sensitivity of judgment-of-learning resolution to past test performance,new learning,and forgetting

When people judge their learning of items across study–test trials, their accuracy in discriminating between learned and unlearned items improves on the second trial. We examined the source of this improvement by estimating the contribution of three factors—memory for past test performance (MPT), new learning, and forgetting—to accuracy on trial 2. In Experiment 1, during an initial trial, participants studied paired associates, made a judgment of learning (JOL) for each one, and were tested. During the second trial, we manipulated two variables: when the JOL was made (either immediately before or after studying an item) and whether participants were told the outcome of the initial recall attempt on trial 1. In Experiment 2, the same procedure was used with a 1-week retention interval between study and test on trial 2. In both experiments, JOL resolution was higher on trial 2 than on trial 1. Fine-grained analyses of JOL magnitude and decomposition of resolution supported several conclusions. First, MPT contributed the most to boosts in JOL magnitude and improvements in resolution across trials. Second, JOLs and subsequent resolution were sensitive to new learning and forgetting, but only when participants’ judgments were made after study. Thus, JOLs appear to integrate information from multiple factors, and these factors jointly contribute to JOL resolution.     

That's More Like It: Multiple Exemplars Facilitate Word Learning

Previous research indicates learning words facilitates categorisation. The current study explores how categorisation affects word learning. In the current study, we investigated whether learning about a category facilitates retention of newly learned words by presenting 2‐year‐old children with multiple referent selection trials to the same object category. In Experiment 1, children either encountered the same exemplar repeatedly or encountered multiple exemplars across trials. All children did very well on the initial task; however, only children who encountered multiple exemplars retained these mappings after a short delay. Experiment 2 replicated and extended this finding by exploring the effect of within‐category variability on children's word retention. Children encountered either narrow or broad exemplars across trials. Again, all children did very well on the initial task; however, only children who encountered narrow exemplars retained mappings after a short delay. Overall, these data offer strong evidence that providing children with the opportunity to compare across exemplars during fast mapping facilitates retention. Copyright © 2013 John Wiley & Sons, Ltd.     

Contribution of perceptual fluency to recognition judgments.

Following a shallow (count vowels) or deep (read) study task, old and new words were tested for both fluency of perception and recognition memory. Subjects first identified a test word as it came gradually into view and then judged it as old or new. Old words were identified faster than new words, indicating implicit, perceptual memory for old words. Independently of this effect, words judged old were identified faster than words judged new, especially after shallow study. Eight experiments examined the possible causal relationship between perceptual fluency and recognition judgements. Experiments 1 to 4 showed that fast identifications per se do not promote old judgments. Accelerating the identification of test items by semantically priming them or making them come more quickly into view did not affect recognition judgments. Experiment 5 showed that the usual association of fast identifications with old judgments is not an artifact of item selection because the association disappeared when the identifications and judgements were segregated into different phases of the test task. Experiments 6 and 7 showed tha the likelihood of old judgments increases directly with the pretested perceptibility of test words, but only after shallow study. Experiment 8 showed that the dependency of recognition judgments on perceptual fluency continues to hold when the requirement to identify the words before judging them is eliminated. We conclude that fluency of perception contributes to recognition judgments, but only when the fluency is produced naturally (e.g., through perceptual memory) and explicit memory is minimal.