The effects of interleaving versus blocking on foreign language pronunciation learning

Many studies have shown that students learn better when they are given repeated exposures to different concepts in a way that is shuffled or interleaved, rather than blocked (e.g., Rohrer Educational Psychology Review, 24, 355–367, 2012). The present study explored the effects of interleaving versus blocking on learning French pronunciations. Native English speakers learned several French words that conformed to specific pronunciation rules (e.g., the long “o” sound formed by the letter combination “eau,” as in bateau), and these rules were presented either in blocked fashion (bateau, carreau, fardeau . . . mouton, genou, verrou . . . tandis, verglas, admis) or in interleaved fashion (bateau, mouton, tandis, carreau, genou, verglas . . .). Blocking versus interleaving was manipulated within subjects (Experiments 1–3) or between subjects (Experiment 4), and participants’ pronunciation proficiency was later tested through multiple-choice tests (Experiments 1, 2, and 4) or a recall test (Experiment 3). In all experiments, blocking benefited the learning of pronunciations more than did interleaving, and this was true whether participants learned only 4 words per rule (Experiments 1–3) or 15 words per rule (Experiment 4). Theoretical implications of these findings are discussed.     

Cross-modal information integration in category learning

An influential theoretical perspective describes an implicit category-learning system that associates regions of perceptual space with response outputs by integrating information preattentionally and predecisionally across multiple stimulus dimensions. In this study, we tested whether this kind of implicit, information-integration category learning is possible across stimulus dimensions lying in different sensory modalities. Humans learned categories composed of conjoint visual–auditory category exemplars comprising a visual component (rectangles varying in the density of contained lit pixels) and an auditory component (in Exp. 1, auditory sequences varying in duration; in Exp. 2, pure tones varying in pitch). The categories had either a one-dimensional, rule-based solution or a two-dimensional, information-integration solution. Humans could solve the information-integration category tasks by integrating information across two stimulus modalities. The results demonstrated an important cross-modal form of sensory integration in the service of category learning, and they advance the field’s knowledge about the sensory organization of systems for categorization.     

Between-list lag effects in recall depend on retention interval

Although the benefits of spaced retrieval for long-term retention are well established, the majority of this work has involved spacing over relatively short intervals (on the order of seconds or minutes). In the present experiments, we evaluated the effectiveness of spaced retrieval across relatively short intervals (within a single session), as compared to longer intervals (between sessions spaced a day apart), for long-term retention (i.e., one day or one week). Across a series of seven experiments, participants (N = 536) learned paired associates to a criterion of 70 % accuracy and then received one test–feedback trial for each item. The test–feedback trial occurred within 10 min of reaching criterion (short lag) or one day later (long lag). Then, a final test occurred one day (Exps. 1–3) or one week (Exps. 4 and 5) after the test–feedback trial. Across the different materials and methods in Experiments 1–3, we found little benefit for the long-lag relative to the short-lag schedule in final recall performance—that is, no lag effect—but large effects on the retention of information from the test–feedback to the final test phase. The results from the experiments with the one-week retention interval (Exps. 4 and 5) indicated a benefit of the long-lag schedule on final recall performance (a lag effect), as well as on retention. This research shows that even when the benefits of lag are eliminated at a (relatively long) one-day retention interval, the lag effect reemerges after a one-week retention interval. The results are interpreted within an extension of the bifurcation model to the spacing effect.     

Retrieval speeds context fluctuation: Why semantic generation enhances later learning but hinders prior learning

In recent work, retrieval has been shown to enhance memory for events following that retrieval. In this set of experiments, we examined the effects of interleaved semantic retrieval on both previous and future learning within a multilist learning paradigm. Interleaved retrieval led to enhanced memory for lists learned following retrieval. In contrast, memory was impaired for lists learned prior to retrieval (Experiment 1). These results are consistent with recent work in multilist learning, directed forgetting, and list-before-last retrieval, all of which indicate a crucial role for retrieval in enhancing mental list segregation. This pattern of results follows clearly from a theoretical perspective in which retrieval drives internal contextual change and in which contextual overlap between study and test promotes better memory. Consistent with that perspective, a 15-min delay before the final test eliminated both effects (Experiment 2). Experiment 2 replicated the results of Experiment 1 with materials and assessments more appropriate for educational settings: Interleaved semantic retrieval led learners to be more able to answer questions correctly about texts studied after a retrieval event but less able to do so for texts studied earlier.     

Prior experience with negative spectral correlations promotes information integration during auditory category learning

Complex sounds vary along a number of acoustic dimensions. These dimensions may exhibit correlations that are familiar to listeners due to their frequent occurrence in natural sounds—namely, speech. However, the precise mechanisms that enable the integration of these dimensions are not well understood. In this study, we examined the categorization of novel auditory stimuli that differed in the correlations of their acoustic dimensions, using decision bound theory. Decision bound theory assumes that stimuli are categorized on the basis of either a single dimension (rule based) or the combination of more than one dimension (information integration) and provides tools for assessing successful integration across multiple acoustic dimensions. In two experiments, we manipulated the stimulus distributions such that in Experiment 1, optimal categorization could be accomplished by either a rule-based or an information integration strategy, while in Experiment 2, optimal categorization was possible only by using an information integration strategy. In both experiments, the pattern of results demonstrated that unidimensional strategies were strongly preferred. Listeners focused on the acoustic dimension most closely related to pitch, suggesting that pitch-based categorization was given preference over timbre-based categorization. Importantly, in Experiment 2, listeners also relied on a two-dimensional information integration strategy, if there was immediate feedback. Furthermore, this strategy was used more often for distributions defined by a negative spectral correlation between stimulus dimensions, as compared with distributions with a positive correlation. These results suggest that prior experience with such correlations might shape short-term auditory category learning.     

The exemplar interleaving effect in inductive learning: Moderation by the difficulty of category discriminations

Recent research demonstrates a spacing effect in inductive learning. Spacing different individual exemplars apart in time, rather than massing them together, aids in the learning of categories. Experiment 1 examined whether it is interleaving or temporal spacing that is critical to the spacing effect in the situation wherethe memory load is high, and the results favored interleaving. Experiment 2 examined the effect of the difficulty of the category discrimination on presentation style (massed vs. spaced) in inductive learning, and the results demonstrated that spacing (i.e., interleaving of exemplars from different categories) is advantageous for low-discriminabilty categories, whereas massing is more effective for high-discriminability categories. In contrast to these performance measures, massing was judged by participants to be more effective than spacing in both discriminability conditions, even when performance for low-discriminability categories showed the opposite.     

Interference of spoken word recognition through phonological priming from visual objects and printed words

Three cross-modal priming experiments examined the influence of preexposure to pictures and printed words on the speed of spoken word recognition. Targets for auditory lexical decision were spoken Dutch words and nonwords, presented in isolation (Experiments 1 and 2) or after a short phrase (Experiment 3). Auditory stimuli were preceded by primes, which were pictures (Experiments 1 and 3) or those pictures’ printed names (Experiment 2). Prime–target pairs were phonologically onset related (e.g., pijl–pijn, arrow–pain), were from the same semantic category (e.g., pijl–zwaard, arrow–sword), or were unrelated on both dimensions. Phonological interference and semantic facilitation were observed in all experiments. Priming magnitude was similar for pictures and printed words and did not vary with picture viewing time or number of pictures in the display (either one or four). These effects arose even though participants were not explicitly instructed to name the pictures and where strategic naming would interfere with lexical decision making. This suggests that, by default, processing of related pictures and printed words influences how quickly we recognize spoken words.     

The effects of list composition and perceptual fluency on judgments of learning (JOLs)

The perceptual fluency hypothesis proposes that items that are easier to perceive at study will be given higher memorability ratings, as compared with less fluent items. However, prior research has examined this metamemorial cue primarily using mixed-list designs. Furthermore, certain memory effects are moderated by the design (mixed list vs. pure list) used to present stimuli. The present study utilized mixed as well as pure lists to assess whether judgments of learning based on perceptual fluency are relative or absolute and whether people are sensitive to differences in recall produced by variation in list composition. Using font size and generation manipulations, Experiments 1 and 2 showed that the effect of perceptual fluency on metamemory is relative in nature, occurring only in mixed lists. Experiments 2 and 3 revealed that metamemory is insensitive to the effect of list composition on recall. These findings are consistent with the assumptions of Koriat’s (Journal of Experimental Psychology: General 126: 349-370, 1997) cue-utilization framework, that JOLs reflect a comparative process and are insensitive to cues pertaining to conditions of learning.     

Putting category learning in order: Category structure and temporal arrangement affect the benefit of interleaved over blocked study

Recent research in inductive category learning has demonstrated that interleaved study of category exemplars results in better performance than does studying each category in separate blocks. However, the questions of how the category structure influences this advantage and how simultaneous presentation interacts with the advantage are open issues. In this article, we present three experiments. The first experiment indicates that the advantage of interleaved over blocked study is modulated by the structure of the categories being studied. More specifically, interleaved study results in better generalization for categories with high within- and between-category similarity, whereas blocked presentation results in better generalization for categories with low within- and between-category similarity. In Experiment 2, we present evidence that when presented simultaneously, between-category comparisons (interleaved presentation) result in a performance advantage for high-similarity categories, but no differences were found for low-similarity categories. In Experiment 3, we directly compared simultaneous and successive presentation of low-similarity categories. We again found an overall benefit for blocked study with these categories. Overall, these results are consistent with the proposal that interleaving emphasizes differences between categories, whereas blocking emphasizes the discovery of commonalities among objects within the same category.     

Investigating the speed–accuracy trade-off: Better use deadlines or response signals?

Deadlines (DLs) and response signals (RSs) are two well-established techniques for investigating speed–accuracy trade-offs (SATs). Methodological differences imply, however, that corresponding data do not necessarily reflect equivalent processes. Specifically, the DL procedure grants knowledge about trial-specific time demands and requires responses before a prespecified period has elapsed. In contrast, RS intervals often vary unpredictably between trials, and responses must be given after an explicit signal. Here, we investigated the effects of these differences in a flanker task. While all conditions yielded robust SAT functions, a right-shift of the curves pointed to reduced performance in RS conditions (Experiment 1, blocked; Experiments 2 and 3, randomized), as compared with DL conditions (Experiments 1–3, blocked), indicating that the detection of the RS imposes additional task demands. Moreover, the flanker effect vanished at long intervals in RS settings, suggesting that stimulus-related effects are absorbed in a slack when decisions are completed prior to the signal. In turn, effects of a flat (Experiment 2) versus a performance-contingent payment (Experiment 3) indicated that susceptibility to response strategies is higher in the DL than in the RS method. Finally, the RS procedure led to a broad range of slow responses and high accuracies, whereas DL conditions resulted in smaller variations in the upper data range (Experiments 1 and 2); with performance-contingent payment (Experiment 3), though, data ranges became similar. Together, the results uncover characteristic procedure-related effects and should help in selection of the appropriate technique.     

Strength cues and blocking at test promote reliable within-list criterion shifts in recognition memory

In seven experiments, we explored the potential for strength-based, within-list criterion shifts in recognition memory. People studied a mix of target words, some presented four times (strong) and others studied once (weak). In Experiments 1, 2, 4A, and 4B, the test was organized into alternating blocks of 10, 20, or 40 trials. Each block contained lures intermixed with strong targets only or weak targets only. In strength-cued conditions, test probes appeared in a unique font color for strong and weak blocks. In the uncued conditions of Experiments 1 and 2, similar strength blocks were tested, but strength was not cued with font color. False alarms to lures were lower in blocks containing strong target words, as compared with lures in blocks containing weak targets, but only when strength was cued with font color. Providing test feedback in Experiment 2 did not alter these results. In Experiments 3A–3C, test items were presented in a random order (i.e., not blocked by strength). Of these three experiments, only one demonstrated a significant shift even though strength cues were provided. Overall, the criterion shift was larger and more reliable as block size increased, and the shift occurred only when strength was cued with font color. These results clarify the factors that affect participants’ willingness to change their response criterion within a test list.     

Category inference as a function of correlational structure, category discriminability, and number of available cues

Two experiments investigated category inference when categories were composed of correlated or uncorrelated dimensions and the categories overlapped minimally or moderately. When the categories minimally overlapped, the dimensions were strongly correlated with the category label. Following a classification learning phase, subsequent transfer required the selection of either a category label or a feature when one, two, or three features were missing. Experiments 1 and 2 differed primarily in the number of learning blocks prior to transfer. In each experiment, the inference of the category label or category feature was influenced by both dimensional and category correlations, as well as their interaction. The number of cues available at test impacted performance more when the dimensional correlations were zero and category overlap was high. However, a minimal number of cues were sufficient to produce high levels of inference when the dimensions were highly correlated; additional cues had a positive but reduced impact, even when overlap was high. Subjects were generally more accurate in inferring the category label than a category feature regardless of dimensional correlation, category overlap, or number of cues available at test. Whether the category label functioned as a special feature or not was critically dependent upon these embedded correlations, with feature inference driven more strongly by dimensional correlations.     

Boundaries of semantic distraction: Dominance and lexicality act at retrieval

Three experiments investigated memory for semantic information with the goal of determining boundary conditions for the manifestation of semantic auditory distraction. Irrelevant speech disrupted the free recall of semantic category- exemplars to an equal degree regardless of whether the speech coincided with presentation or test phases of the task (Experiment 1), and this occurred regardless of whether it comprised random words or coherent sentences (Experiment 2). The effects of background speech were greater when the irrelevant speech was semantically related to the to-be-remembered material, but only when the irrelevant words were high in output dominance (Experiment 3). The implications of these findings in relation to the processing of task material and the processing of background speech are discussed.     

Generalization to unfamiliar talkers in artificial language learning

While there is evidence that talker-specific details are encoded in the phonetics of the lexicon (Kraljic, Samuel, & Brennan, Psychological Science 19(4):332–228, 2008; Logan, Lively, & Pisoni, Journal of the Acoustical Society of America, 89(2):874-886, 1991) and in sentence processing (Nygaard & Pisoni, Perception & Psychophysics, 60(3):355–376, 1998), it is unclear whether categorical linguistic patterns are also represented in terms of talker-specific details. The present study provides evidence that adult learners form talker-independent representations for productive linguistic patterns. Participants were able to generalize a novel linguistic pattern to unfamiliar talkers. Learners were exposed to spoken words that conformed to a pattern in which vowels of a word agreed in place of articulation, referred to as vowel harmony. All items were presented in the voice of one single talker. Participants were tested on items that included both the familiar talker and an unfamiliar talker. Participants generalized the pattern to novel talkers when the talkers spoke with a familiar accent (Experiment 1), as well as with an unfamiliar accent (Experiment 2). Learners showed a small advantage for talker familiarity when the words were familiar, but not when the words were novel. These results are consistent with a theory of language processing in which the lexicon stores fine-grained, talker-specific phonetic details, but productive linguistic processes are subject to abstract, talker-independent representations.     

Prior knowledge is more predictive of error correction than subjective confidence

Previous research has demonstrated that, when given feedback, participants are more likely to correct confidently-held errors, as compared with errors held with lower levels of confidence, a finding termed the hypercorrection effect. Accounts of hypercorrection suggest that confidence modifies attention to feedback; alternatively, hypercorrection may reflect prior domain knowledge, with confidence ratings simply correlated with this prior knowledge. In the present experiments, we attempted to adjudicate among these explanations of the hypercorrection effect. In Experiments 1a and 1b, participants answered general knowledge questions, rated their confidence, and received feedback either immediately after rating their confidence or after a delay of several minutes. Although memory for confidence judgments should have been poorer at a delay, the hypercorrection effect was equivalent for both feedback timings. Experiment 2 showed that hypercorrection remained unchanged even when the delay to feedback was increased. In addition, measures of recall for prior confidence judgments showed that memory for confidence was indeed poorer after a delay. Experiment 3 directly compared estimates of domain knowledge with confidence ratings, showing that such prior knowledge was related to error correction, whereas the unique role of confidence was small. Overall, our results suggest that prior knowledge likely plays a primary role in error correction, while confidence may play a small role or merely serve as a proxy for prior knowledge.     

Top-down constraint on recognition memory

Can recognition memory be constrained “at the front end,” such that people are more likely to retrieve information about studying a recognition-test probe from a specified target source than they are to retrieve such information about a probe from a nontarget source? We adapted a procedure developed by Jacoby, Shimizu, Daniels, and Rhodes (Psychonomic Bulletin & Review 12:852–857, 2005) to address this question. Experiment 1 yielded evidence of source-constrained retrieval, but that pattern was not significant in Experiments 2, 3, and 4 (nor in several unpublished pilot experiments). In Experiment 5, in which items from the two studied sources were perceptibly different, a pattern consistent with front-end constraint of recognition emerged, but this constraint was likely exercised via visual attention rather than memory. Experiment 6 replicated both the absence of a significant constrained-retrieval pattern when the sources did not differ perceptibly (as in Exps. 2, 3 and 4) and the presence of that pattern when they did differ perceptibly (as in Exp. 5). Our results suggest that people can easily constrain recognition when items from the to-be-recognized source differ perceptibly from items from other sources (presumably via visual attention), but that it is difficult to constrain retrieval solely on the basis of source memory.     

The role of Gestalt grouping principles in visual statistical learning

A major issue in visual scene recognition involves the extraction of recurring chunks from a sequence of complex scenes. Previous studies have suggested that this kind of learning is accomplished according to Bayesian principles that constrain the types of extracted chunks. Here we show that perceptual grouping cues are also incorporated in this Bayesian model, providing additional evidence for the possible span of chunks. Experiment 1 replicates previous results showing that observers can learn three-element chunks without learning smaller, two-element chunks embedded within them. Experiment 2 shows that the very same embedded chunks are learned if they are grouped by perceptual cues, suggesting that perceptual grouping cues play an important role in chunk extraction from complex scenes.