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Purpose: Previous studies have reported the success of distributional learning for adult speakers across segmental and suprasegmental categories immediately after training. On the other hand, second language (L2) perception models posit that the ease with which learners perceive a nonnative speech contrast depends on the perceptual mapping between the contrast and learners' first language (L1) categories. This study examined whether a difference in perceptual mapping patterns for different L2-Mandarin tonal contrasts might result in a difference in distributional learning effectiveness for tonal speakers and whether an interval of sleep enhanced the knowledge through consolidation. Method: Following a pretest-training-posttest design, 66 L1-Cantonese participants with fewer than 9 years of Mandarin training were assigned to either the bimodal or unimodal distribution conditions. The participants of each group were asked to discriminate Mandarin level-falling (T1-T4) and level-rising (T1-T2) tone pairs on novel syllables in a within-subject design. All participants were trained in the evening, tested after training, and returned after 12 hr for overnight consolidation assessment. Results: A significant distributional learning effect was observed for Mandarin T1-T4, but only after sleep. No significant distributional learning effect was observed for Mandarin T1-T2, either after training or after sleep. Conclusions: The findings may imply that distributional learning is contingent on perceptual mapping patterns of the target contrasts and that sleep may play a role in the consolidation of knowledge in an implicit statistical learning paradigm.

Are there some differences so small that we cannot detect them? Are some quantities so similar (e.g., the number of spots on two speckled hens) that they simply look the same to us? Although modern psychophysical theories such as Signal Detection Theory would predict that, with enough trials, even minute differences would be perceptible at an above-chance rate, this prediction has rarely been empirically tested for any psychological dimension, and never for the domain of number perception. In an experiment with over 400 adults, we find that observers can distinguish which of two collections has more dots from a brief glance. Impressively, observers performed above chance on every numerical comparison tested, even when discriminating a comparison as difficult as 50 versus 51 dots. Thus, we present empirical evidence that numerical discrimination abilities, consistent with SDT, are remarkably fine-grained.

We evaluated the effects of a discrimination training procedure for establishing praise as a reinforcer for three children with autism spectrum disorder. After establishing two praise words as discriminative stimuli and two nonsense words as S-deltas, we evaluated whether the stimuli then functioned as reinforcers by presenting each stimulus as a consequence for a new response. The results demonstrated that previously neutral praise words functioned as reinforcers and nonsense words did not. As in previous studies on establishing reinforcers, the effects were transitory, and praise words did not continue to function as reinforcers after repeated exposure without discrimination training. Recommendations are provided for future research and maintaining reinforcement effects.

Sequence learning is fundamental to a wide range of cognitive functions. Explaining how sequences--and the relations between the elements they comprise--are learned is a fundamental challenge to cognitive science. However, although hundreds of articles addressing this question are published each year, the actual learning mechanisms involved in the learning of sequences are rarely investigated. We present three experiments that seek to examine these mechanisms during a typing task. Experiments 1 and 2 tested learning during typing single letters on each trial. Experiment 3 tested for "chunking" of these letters into "words." The results of these experiments were used to examine the mechanisms that could best account for them, with a focus on two particular proposals: statistical transitional probability learning and discriminative error-driven learning. Experiments 1 and 2 showed that error-driven learning was a better predictor of response latencies than either n-gram frequencies or transitional probabilities. No evidence for chunking was found in Experiment 3, probably due to interspersing visual cues with the motor response. In addition, learning occurred across a greater distance in Experiment 1 than Experiment 2, suggesting that the greater predictability that comes with increased structure leads to greater learnability. These results shed new light on the mechanism responsible for sequence learning. Despite the widely held assumption that transitional probability learning is essential to this process, the present results suggest instead that the sequences are learned through a process of discriminative learning, involving prediction and feedback from prediction error.

Previous research has suggested that infants are able to distinguish between possible and impossible events and make basic probabilistic inferences. However, much of this research has focused on children's intuitions about past events for which the outcome is already determined but unknown. Here, we investigated children's ability to use probabilistic information to guide their choices and actively shape future events. In two experiments, we examined whether children could successfully direct a marble through a series of tubes, selecting between routes where success was possible, impossible, or guaranteed (i.e., 50% vs. 0%, or 50% vs. 100%; Experiment 1), and routes where success was mutually possible but probabilistically distinct (e.g., 33% vs. 50%; Experiment 2). In total, we tested 136 two- to five-year-old children (76 males), recruited predominantly through a museum in Brisbane, Australia. In Experiment 1, we found that while younger children typically did not perform above chance, the vast majority of 4- and 5-year-olds consistently distinguished between possible and impossible or guaranteed outcomes. In Experiment 2, children of all ages had greater difficulty with distinguishing between two possible outcomes with different likelihoods than between possible and impossible/guaranteed outcomes, although some individual 4- and 5-year-olds demonstrated competence when making both distinctions.

In the field of stimulus generalization, an old yet unresolved discussion pertains to what extent stimulus misidentifications contribute to the pattern of conditioned responding. In this article, we perform cluster analysis on six datasets (four published datasets and two unpublished datasets, included N = 950) to examine the relationship between interindividual differences in (a) stimulus identification, (b) patterns of generalized responding, and (c) verbalized generalization rules. The datasets were obtained from online predictive learning tasks where participants learned associations between colored cues and the presence or absence of a hypothetical outcome. In these datasets, stimulus identification and expectancy ratings were assessed in separate phases to a range of colors varying between blue-green. Using cluster analyses on performance during stimulus identification, we identified different subgroups of participants (good vs. bad identifiers). In all six datasets, we found a close relationship between the pattern of stimulus identification and the shape of the expectancy gradient across the test dimension between the identified subgroups. Furthermore, participants classified as good identifiers were more likely to report a similarity generalization rule than a relational or linear rule, suggesting that individual differences in stimulus identification are related to individual differences in generalization rules. These findings suggest that greater consideration should be given to interindividual variability in stimulus identification, inductive rules, and their relationship in explaining patterns of generalized responses.

We examined whether theory of mind difficulties often considered to characterise autistic individuals impair their ability to detect the presence of dodgy or suspicious behaviour in interactions, thereby rendering them especially vulnerable to becoming involved in criminal activity or being victimised. Using a signal detection theory approach, we compared autistic (N = 72; Verbal Comprehension Index = 88-122, M = 106.6) and non-autistic (N = 70; Verbal Comprehension Index = 86-120, M = 104.4) adults' ability to detect dodgy or suspicious behaviour across a broad array of scenarios (N = 136). Although theory of mind performance was poorer for the autistic group, frequentist and Bayesian analyses indicated there were no group differences in either the standard measures of discrimination performance obtainable using a signal detection theory approach or in terms of a bias towards reporting dodgy behaviour. Furthermore, there was no indication of a relationship between dodginess detection and autistic traits. However, regardless of group membership, theory of mind difficulties were associated with poorer discrimination of dodgy behaviour, highlighting an individual difference variable that may increase the vulnerability of both autistic and non-autistic individuals to involvement in some form of criminal activity or to becoming a victim of crime.

Research has consistently demonstrated that learners are strikingly poor at metacognitively monitoring their learning and comprehension of texts. The aim of the present meta-analysis is to explore three important questions about metacomprehension: (a) To what extent can people accurately discriminate well-learned texts from less well learned ones? (b) What are the (meta)cognitive causes of poor metacomprehension accuracy? and (c) What interventions improve the accuracy of metacomprehension judgments? In total, the meta-analysis integrated 502 effects and data from 15,889 participants across 115 studies to assess these questions. The results showed a weighted mean correlation of 0.178 for nonintervention effects. Many interventions were shown to be effective, such as delayed summary writing and delayed keyword generation. In addition, combining different interventions tended to generate additive benefits. The findings support the transfer-appropriate monitoring account, the situation model framework, and the poor-comprehension theory as explanations for why metacomprehension accuracy is typically poor. Practical implications are discussed.

Prosody is the fundamental organizing principle of spoken language, carrying lexical, morphosyntactic, and pragmatic information. It, therefore, provides highly relevant input for language development. Are infants sensitive to this important aspect of spoken language early on? In this study, we asked whether infants are able to discriminate well-formed utterance-level prosodic contours from ill-formed, backward prosodic contours at birth. This deviant prosodic contour was obtained by time-reversing the original one, and super-imposing it on the otherwise intact segmental information. The resulting backward prosodic contour was thus unfamiliar to the infants and ill-formed in French. We used near-infrared spectroscopy (NIRS) in 1-3-day-old French newborns (n = 25) to measure their brain responses to well-formed contours as standards and their backward prosody counterparts as deviants in the frontal, temporal, and parietal areas bilaterally. A cluster-based permutation test revealed greater responses to the Deviant than to the Standard condition in right temporal areas. These results suggest that newborns are already capable of detecting utterance-level prosodic violations at birth, a key ability for breaking into the native language, and that this ability is supported by brain areas similar to those in adults.

Accumulating evidence suggests that there is a spontaneous preference for numerical, compared to non-numerical (e.g., cumulative surface area), information. However, given a paucity of research on the perception of non-numerical magnitudes, it is unclear whether this preference reflects a specific bias towards number, or a general bias towards the more perceptually discriminable dimension (i.e., number). Here, we found that when the number and area of visual dot displays were matched in mathematical ratio, number was more perceptually discriminable than area in both adults and children. Moreover, both adults and children preferentially categorized these ratio-matched stimuli based on number, consistent with previous work. However, when number and area were matched in perceptual discriminability, a different pattern of results emerged. In particular, children preferentially categorized stimuli based on area, suggesting that children's previously observed number bias may be due to a mismatch in the perceptual discriminability of number and area, not an intrinsic salience of number. Interestingly, adults continued to categorize the displays on the basis of number. Altogether, these findings suggest a dominant role for area during childhood, refuting the claim that number is inherently and uniquely salient. Yet they also reveal an increased salience of number that emerges over development. Potential explanations for this developmental shift are discussed.

Recent work has investigated the origin of infant colour categories, showing pre-linguistic infants categorise colour even in the absence of colour words. These infant categories are similar but not identical to adult categories, giving rise to an important question about how infant colour perception changes with the learning of colour words. Here we present two novel paradigms in which 12- and 19-month-old participants learning English as their first language were assessed on their perception of colour, while data on their colour word comprehension were also collected. Results indicate that participants' perception of colours close to the colour category boundaries dramatically change after colour word learning. The results highlight the shift made from infant colour categories to adult-like linguistically mediated colour categories that accompanies colour word learning.

This study purports to bridge the gap in research directed at people with Low Functioning Autism (LFA) by exploring if sensory discrimination ability can be used to assess cognitive functioning in children with LFA. The study was done in two phases: (i) a pilot phase (with 4 male participants; mean age = 3 years 6.5 months)--which tried to validate whether the paradigm of 'visual paired comparison' procedure (Fantz, Science, 146, 668-670, 1964) can be effectively used in measurement of perceptual judgment of LFA, diagnosed on the basis of 'Autism Diagnostic Checklist' by Banerjee ("Indian Journal of Clinical Psychology," 34, 83-93, 2007). (ii) A main phase (with 20 participants; male = 18, female = 2; mean age = 4 years 8 months)--which determined sensory discrimination ability in LFA in the auditory and visual modality and related the findings with the sensory threshold of the children by using 'The Sensory Profile' (Kumar and Banerjee, "Development of sensory integration therapeutic module for autism and its effect on some functional areas of autism." Unpublished Ph.D Thesis, 2011). The results reveal that the 'Visual Paired Comparison' paradigm can be used as a tool to discern sensory discrimination ability in children with Low Functioning Autism. Also, sensory discrimination can be used to differentiate the cognitive ability of children with Low Functioning Autism. The behavioural repertoire of sensory discrimination is associated with the sensory threshold of the participants.

Purpose: Reduced use of visible articulatory information on a speaker's face has been implicated as a possible contributor to language deficits in autism spectrum disorders (ASD). We employ an audiovisual (AV) phonemic restoration paradigm to measure behavioral performance (button press) and event-related potentials (ERPs) of visual speech perception in children with ASD and their neurotypical peers to assess potential neural substrates that contribute to group differences. Method: Two sets of speech stimuli, /ba/-"/a/" ("/a/" was created from the /ba/ token by a reducing the initial consonant) and /ba/-/pa/, were presented within an auditory oddball paradigm to children aged 6-13 years with ASD (n = 17) and typical development (TD; n = 33) within two conditions. The AV condition contained a fully visible speaking face; the pixelated (PX) condition included a face, but the mouth and jaw were PX, removing all articulatory information. When articulatory features were present for the /ba/-"/a/" contrast, it was expected that the influence of the visual articulators would facilitate a phonemic restoration effect in which "/a/" would be perceived as /ba/. ERPs were recorded during the experiment while children were required to press a button for the deviant sound for both sets of speech contrasts within both conditions. Results: Button press data revealed that TD children were more accurate in discriminating between /ba/-"/a/" and /ba/-/pa/ contrasts in the PX condition relative to the ASD group. ERPs in response to the /ba/-/pa/ contrast within both AV and PX conditions differed between children with ASD and TD children (earlier P300 responses for children with ASD). Conclusion: Children with ASD differ in the underlying neural mechanisms responsible for speech processing compared with TD peers within an AV context.

This article presents and analyses a didactic proposal based on manipulative material (Knobless Cylinders) used in a Montessori classroom of 3-6-year-old pre-schoolers. Choosing this material is justified in relation to the competencies/strategies/skills used during the development of mathematical patterning. Numerous studies emphasise the importance of patterns in mathematics and experimental sciences instruction from early childhood onward. However, there are several educational factors that have not yet been clarified, such as meaningful learning, the overuse of abstract visual patterns that are distant from the student's previous life experience, etc. This article discusses the sequence of proposed activities and certain critical issues.

Perception is not an independent, in-the-moment event. Instead, perceiving involves integrating prior expectations with current observations. How does this ability develop from infancy through adulthood? We examined how prior visual experience shapes visual perception in infants, children, and adults. Using an identical task across age groups, we exposed participants to pairs of colorful stimuli and implicitly measured their ability to discriminate relative saturation levels. Results showed that adult participants were biased by previously experienced exemplars, and exhibited weakened in-the-moment discrimination between different levels of saturation. In contrast, infants and children showed less influence of memory in their perception, and they actually outperformed adults in discriminating between current levels of saturation. Our findings suggest that as humans develop, their perception relies more on prior experience and less on current observation.

One of the most fundamental strategies in mathematics instruction is practice problems because teachers know that practicing a skill improves performance. At the same time, teachers also know that just because students can correctly answer practice problems does not mean they fully understand the concept or how to apply a formula--especially not in the long term. Because students understand a key concept in seventh grade does not guarantee they will understand or remember the same concept in eighth grade. So the question is this: How can math teachers ensure that students are learning math and improving their skills, both in the short term and the long term? As described in the book "Powerful Teaching: Unleash the Science of Learning," research by cognitive scientists demonstrates that interleaving, or the simple strategy of mixing up concepts to be learned, can increase (and even double) math learning. The authors describe how to implement this strategy quickly and effectively in the classroom.

In recognition memory, anything that is objectively new is necessarily not-old, and anything that is objectively old is necessarily not-new. Therefore, judging whether a test item is new is logically equivalent to judging whether it is old, and conversely. Nevertheless, a series of 10 experiments showed that old? and new? judgments did not produce equivalent recognition accuracy. In Experiments 1-4, wherein subjects made old? or new? judgments about test items, new? judgments yielded more accurate performance for old items than old? judgments did, and old? judgments yielded more accurate performance for new items than new? judgments did. This same violation of logical equivalence was observed in Experiments 5-10, wherein subjects made similar? judgments as well as old? and new? ones. In short, old? and new? judgments displayed consistent Judgment × Item crossovers, rather than equivalence. Response latencies were used to test the hypothesis that Judgment × Item crossovers were due to certain judgment-item combinations provoking more deliberate, thorough retrieval than other combinations. There was no support for that hypothesis, but the data were consistent with an earlier theory, which posits that latency depends on the extent to which judgments or items slant retrieval toward accessing verbatim traces.

In a novel version of the classic dot-pattern prototype-distortion paradigm of category learning, Homa et al. (2019) tested a condition in which individual training instances never repeated, and observed results that they claimed severely challenged exemplar models of classification and recognition. Among the results was a dissociation in which participants classified transfer items with high accuracy in the no-repeat condition, yet in old-new recognition tests showed no ability to discriminate between old and new items of the same level of distortion from the prototype. In addition, speed of classification learning was no faster in a condition in which a small set of training instances was repeated continuously compared with the no-repeat condition. Here we show through computer-simulation modeling that exemplar models naturally capture the classification-recognition dissociation in the no-repeat condition, as well as a wide variety of other qualitative effects reported by Homa et al. (2019). We also conduct new conceptual-replication experiments to investigate their reported null effect of repeated versus nonrepeated training instances on speed of classification learning. In contrast to Homa et al. (2019) we find that speed of learning is substantially faster in the repeat condition than in the no-repeat condition, precisely as exemplar models predict. The exemplar model also captures a wide variety of transfer effects observed following the completion of category learning, including the classification-recognition dissociation observed across the repeat and no-repeat conditions.

Much recent research and theorizing in the field of reasoning has been concerned with intuitive sensitivity to logical validity, such as the logic-brightness effect, in which logically valid arguments are judged to have a "brighter" typeface than invalid arguments. We propose and test a novel signal competition account of this phenomenon. Our account makes two assumptions: (a) as per the demands of the logic-brightness task, people attempt to find a perceptual signal to guide brightness judgments, but (b) when the perceptual signal is hard to discern, they instead attend to cues such as argument validity. Experiment 1 tested this account by manipulating the difficulty of the perceptual contrast. When contrast discrimination was relatively difficult, we replicated the logic-brightness effect. When the discrimination was easy, the effect was eliminated. Experiment 2 manipulated the ambiguity of the perceptual task, comparing discrimination performance when the perceptual contrast was labeled in terms of rating "brightness" or "darkness". When the less ambiguous darkness labeling was used, there was no evidence of a logic-brightness effect. In both experiments, individual sensitivity to the perceptual discrimination was negatively correlated with sensitivity to argument validity. Hierarchical latent mixture modeling revealed distinct individual strategies: responses based on perceptual cues, responses based on validity or guessing. Consistent with the signal competition account, the proportion of those responding to validity increased with perceptual discrimination difficulty or task ambiguity. The results challenge explanations of the logic-brightness effect based on parallel dual-process models of reasoning.

The quest for determining the degree of learning difficulty associated with different types of categories has been instrumental in our understanding of human categorization behavior and, more broadly, human generalization. For instance, we now know that the topological nature of the dimensions (e.g., whether these are integral or separable) that define the family of categories generated with three binary dimensions yield two different learning difficulty orderings. In our study, for the first time, we replicated one such classic ordering involving integral dimensions and explored the impact that the choice of dimensional values, along with the nature of the stimulus presentation, had on learning difficulty during the learning phase of our four experiments. Two standard orderings were observed in our investigation which were consistent with the hypothesis that multilevel discrimination plays a key role in concept learning. We accounted for our empirical results by making this role explicit at three levels, the feature, object, and category structure levels, using a dual discrimination invariance model (DDIM) derived from the core invariance law of generalized invariance structure theory (GIST). The model involves a "discrimination switch" via what is referred to in GIST as the "tau discrimination threshold" where two distinct extreme degrees of discrimination yield two fundamental learning difficulty orderings able to account for results from our experiments without free parameters. We then show how the DDIM is not only a more accurate and general predictor than the best alternatives but also provides a plausible and tenable cognitive mechanism for understanding these behaviors.

Dyslexia has frequently been related to atypical auditory temporal processing and speech perception. Results of studies emphasizing speech onset cues and reinforcing the temporal structure of the speech envelope, that is, envelope enhancement (EE), demonstrated reduced speech perception deficits in individuals with dyslexia. The use of this strategy as auditory intervention might thus reduce some of the deficits related to dyslexia. Importantly, reading-skill interventions are most effective when they are provided during kindergarten and first grade. Hence, we provided a tablet-based 12-week auditory and phonics-based intervention to pre-readers at cognitive risk for dyslexia and investigated the effect on auditory temporal processing with a rise time discrimination (RTD) task. Ninety-one pre-readers at cognitive risk for dyslexia (aged 5-6) were assigned to two groups receiving a phonics-based intervention and playing a story listening game either with (n = 31) or without (n = 31) EE or a third group playing control games and listening to non-enhanced stories (n = 29). RTD was measured directly before, directly after and 1 year after the intervention. While the groups listening to non-enhanced stories mainly improved after the intervention during first grade, the group listening to enhanced stories improved during the intervention in kindergarten and subsequently remained stable during first grade. Hence, an EE intervention improves auditory processing skills important for the development of phonological skills. This occurred before the onset of reading instruction, preceding the maturational improvement of these skills, hence potentially giving at risk children a head start when learning to read. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=e0BfT4dGXNA

This research aims to explore the ability of English majors to identify the four basic types of sentences. English language has four types of sentences, each kind of sentence for different kinds of messages. Sentences are combinations of words that express complete thoughts. Sentences are basic building blocks of writing and communication; therefore, breaking our ideas into sentences is essential for clear communication. In traditional grammar, the four basic types of sentence structures are the simple sentence, the compound sentence, the complex sentence, and the compound-complex sentence, whose identification by the non-native student teachers may be problematic. It's crucial that English majors recognize word order and sentence types in English to improve their academic writing skills, and hence the identification of four types of sentences by English majors is a must. In this research 35 English majors with low intermediate background were given a pretest of 20 questions in terms of a multiple-choice test to measure their initial success at the beginning. After 6 hours of intense sentence structure recognition studies, they were given the same pretest, after al elapse of 15 days, as the posttest to determine their final success on the discrimination of simple, compound, complex sentences, and compound-complex sentences from each other. After the collection of data from pre-test and post-tests, the data were analyzed by SPSS 21. It was discovered that while pre-test's was 23%, the mean score of the post-test came up to be 56%, the percentage of ascent being % 23.

During exploration, young children often show an intuitive sensitivity to uncertainty, despite their strong tendency towards overconfidence in their explicit judgments. Here, we examine the development of children's explicit and implicit recognition of uncertainty using the same stimuli. We presented 4- and 5-year-olds with objects that varied in their amount of perceptual occlusion, and assessed their ability to distinguish among them using two types of measures. Experiment 1 used a traditional 3-point confidence scale to examine children's explicit uncertainty judgments. We compared these confidence judgments before and after they observed disconfirming evidence, to assess the impact of this experience on their acknowledgement of uncertainty in later trials. Experiment 2 examined children's exploration preference as a measure of implicit sensitivity to uncertainty. Our results indicate that children intuitively recognize gaps in their knowledge, and that this implicit recognition may be leveraged to support their explicit judgments. Specifically, we found that children's baseline confidence judgments improved significantly following the presentation of disconfirming evidence. Furthermore, when asked to make exploration decisions about the same set of objects, children showed a spontaneous sensitivity to uncertainty, prior to any evidence. Taken together, these results suggest that children's exploration behavior may be used as an early developing measure of uncertainty control and raise the intriguing possibility that the experience of unexpected outcomes may play a role in the development of metacognition.

It is common to see mirror errors in letters in early stages of reading due to the mirror-generalization process that allows a visual stimulus to be identified independently of its orientation. To avoid such errors, this process must be inhibited. A special case would be children with dyslexia since their difficulties with the alphabetic code may also delay the acquisition of correct letter orientation. We investigated the relationship between reversible errors in reading and dyslexia. Twenty-seven Spanish-speaking children with dyslexia (7-12 years old) and 27 chronological-age-matched controls performed a 'same-different' letter decision task on reversible and non-reversible letters. Results showed that all participants required more time and committed more errors in discriminating reversible letters. In addition, worse execution was observed in the dyslexic group, which seems to indicate that this group is delayed in the acquisition of correct letter orientation. Therefore, our results indicated that overcoming reading errors in mirrors depends to some extent on the reading competence of the children and the ability to inhibit the process of generalization of mirrors.

How do children learn to communicate, and what do they learn? Traditionally, most theories have taken an associative, compositional approach to these questions, supposing children acquire an inventory of form-meaning associations, and procedures for composing / decomposing them; into / from messages in production and comprehension. This paper presents an alternative account of human communication and its acquisition based on the systematic, discriminative approach embodied in psychological and computational models of learning, and formally described by communication theory. It describes how discriminative learning theory offers an alternative perspective on the way that systems of semantic cues are conditioned onto communicative codes, while information theory provides a very different view of the nature of the codes themselves. It shows how the distributional properties of languages satisfy the communicative requirements described in information theory, enabling language learners to align their expectations despite the vastly different levels of experience among language users, and to master communication systems far more abstract than linguistic intuitions traditionally assume. Topics reviewed include morphological development, the acquisition of verb argument structures, and the functions of linguistic systems that have proven to be stumbling blocks for compositional theories: grammatical gender and personal names.

Individuals diagnosed with autism spectrum disorder (ASD) who engage in stereotypy may also emit a prior, temporally contiguous, high-risk response to access stereotypic behaviors. For example, the participant in this study who was diagnosed with ASD engaged in a chained response that included elopement, often in unsafe locations, to access light switch flipping. Previous research indicates that functional communication training (FCT) with delay fading is a viable approach to reduce chained problem behavior. In this study, we extended previous research by (a) evaluating the generalized effect of FCT and schedule thinning using multiple schedule technology for an automatically maintained chained response, and (b) evaluating whether intervention effects maintained in the participant's optimal context. Results for the participant suggested that FCT with schedule thinning mitigated high-risk chained responding across settings and discrimination training using a multiple schedule assessment effectively signaled available and unavailable times for the participant to emit the chained response which matched the participant's natural schedule parameters.

In the present study, two typically developing 4-year-old children, Pete and Joe, were trained six conditional discriminations and tested for the formation of three 3-member equivalence classes. Pete and Joe did not establish the AC relation within 600 trials and were given two conditions of preliminary training, including naming of stimuli with two different stimulus sets. Pete started with preliminary training with common naming of stimuli, followed by conditional-discrimination training and testing for emergent relations, and continued with preliminary training on individual naming of stimuli, followed by the same training and testing as described previously. Joe experienced the same conditions but in reversed order. Pete responded in accordance with equivalence in the second round in the condition with common naming. In the first round of testing in the condition with individual naming, he responded in accordance with equivalence. In the condition with individual naming, Joe did not respond in accordance with stimulus equivalence but established all of the directly trained relations during training. In the condition with common naming, he responded in accordance with equivalence in the first round of testing. The results from the experiment support earlier findings that both common and individual naming could facilitate the emergence of equivalence classes.

Most eyewitness identification research simulates single perpetrator crimes, but real-world crimes often transpire at the hands of multiple perpetrators. It is unclear how multiple perpetrators might impact the ability of eyewitnesses to discriminate between the guilty and innocent. To address this issue, we conducted two experiments in which large nationwide samples of participants read a vignette about a crime being committed, and then viewed one to two target faces. If there were two targets, they were either similar or dissimilar, and presented either simultaneously or sequentially. Participants later viewed a target-present or -absent lineup for each target. As predicted, presenting one target enhanced discriminability compared to two targets presented simultaneously (Experiments 1 and 2), and two targets presented sequentially (Experiment 2). Results were mixed regarding the effect of similarity, with discriminability better for dissimilar compared to similar target pairs in just one experiment. Lastly, high confidence indicated high accuracy across all conditions.

Often, the evidence we observe is consistent with more than one explanation. How do learners discriminate among candidate causes? The current studies examine whether counterfactuals help 5-year olds (N = 120) select between competing hypotheses and compares the effectiveness of these prompts to a related scaffold. In Experiment 1, counterfactuals support evidence evaluation, leading children to privilege and extend the cause that accounted for more data. In Experiment 2, the hypothesis that accounted for the most evidence was pitted against children's prior beliefs. Children who considered alternative outcomes privileged the hypothesis that accounted for more observations, whereas those who explained relied on prior beliefs. Findings demonstrate that counterfactuals recruit attention to disambiguating evidence and outperform explanation when data contrast with existing beliefs.

A portion of children diagnosed with autism spectrum disorder (ASD) have difficulty acquiring conditional discrimination. However, previous researchers suggested that the discrimination of nonverbal auditory stimuli may be acquired more efficiently (Eikeseth & Hayward, 2009; Uwer, et al., 2002). For example, a child may learn to touch a picture of a piano after hearing the musical instrument more quickly than when the auditory stimulus is the spoken word "piano." The purpose of the present study was to extend previous research by assessing the acquisition of conditional discriminations with sample stimuli presented as either automated spoken words or high- and low-disparity nonverbal auditory stimuli (i.e., environmental sounds). Conditional discriminations with high-disparity environmental sounds as sample stimuli were acquired rather than or more efficiently than those trained with low-disparity environmental sounds and words as sample stimuli.

Young children are sensitive to both numerical and spatial magnitude cues early in development, but many questions remain about how children's attention to magnitudes relates to their early math achievement. In two studies, we tested three hypotheses related to the flexible attention to magnitudes (FAM) account, which suggests that young children's flexible attention to both numerical and spatial magnitudes is an important predictor of early math success. In Study 1, we recruited 318 preschool-age children (51.5% female; M[subscript age] = 54.7 months, SD[subscript age] = 4.24 months) and assessed them at two time points on a battery of math, executive function, and language measures, including a novel assessment of FAM ability developed for this study. Consistent with our hypotheses, we found that young children had specific difficulty flexibly shifting between numerical and spatial magnitudes, that their FAM ability was related to both their executive function and math skills controlling for covariates, and finally that their FAM ability at the first time point was predictive of their math achievement growth over time controlling for executive function skills and covariates. In Study 2, we recruited 157 preschool-age children (47.4% female; M[subscript age] = 53.36 months, SD[subscript age] = 7.17 months). We replicated the findings of Study 1 and extended them to account for children's non-symbolic numerical magnitude discrimination skills. Implications of the results of these studies for early math activities development are discussed.

Linguistic category learning has been shown to be highly sensitive to linear order, and depending on the task, differentially sensitive to the information provided by preceding category markers ("premarkers," e.g., gendered articles) or succeeding category markers ("postmarkers," e.g., gendered suffixes). Given that numerous systems for marking grammatical categories exist in natural languages, it follows that a better understanding of these findings can shed light on the factors underlying this diversity. In two discriminative learning simulations and an artificial language learning experiment, we identify two factors that modulate linear order effects in linguistic category learning: category structure and the level of abstraction in a category hierarchy. Regarding category structure, we find that postmarking brings an advantage for learning category diagnostic stimulus dimensions, an effect not present when categories are non-confusable. Regarding levels of abstraction, we find that premarking of super-ordinate categories (e.g., noun class) facilitates learning of subordinate categories (e.g., nouns). We present detailed simulations using a plausible candidate mechanism for the observed effects, along with a comprehensive analysis of linear order effects within an expectation-based account of learning. Our findings indicate that linguistic category learning is differentially guided by pre- and postmarking, and that the influence of each is modulated by the specific characteristics of a given category system.

Failure to learn and generalize abstract relational rules has critical implications for education. In this study, we aimed to determine which training conditions facilitate relational transfer in a relatively simple (patterning) discrimination versus a relatively complex (biconditional) discrimination. The amount of training participants received had little influence on rates of relational transfer. Instead, trial-sequencing of the training contingencies influenced relational transfer in different ways depending on the complexity of the discrimination. Clustering instances of relational rules together during training improved transfer of both simpler patterning and more difficult biconditional rules, regardless of individual differences in cognitive reflection. However, blocking all trials of the same type together improved rule transfer only for biconditional discriminations. Individual differences in cognitive reflection were also more predictive of relational rule use under suboptimal training conditions. The results highlight the need for comprehensive accounts of relational learning to consider how learning conditions and individual differences affect the likelihood of engaging in learning relational structures.

Building conceptual knowledge that generalizes to novel situations is a key function of human memory. Category-learning paradigms have long been used to understand the mechanisms of knowledge generalization. In the present study, we tested the conditions that promote formation of new concepts. Participants underwent 1 of 6 training conditions that differed in the number of examples per category (set size) and their relative similarity to the category average (set coherence). Performance metrics included rates of category learning, ability to generalize categories to new items of varying similarity to prototypes, and recognition memory for individual examples. In categorization, high set coherence led to faster learning and better generalization, while set size had little effect. Recognition did not differ reliably among conditions. We also tested the nature of memory representations used for categorization and recognition decisions using quantitative prototype and exemplar models fit to behavioral responses. Prototype models posit abstract category representations based on the category's central tendency, whereas exemplar models posit that categories are represented by individual category members. Prototype strategy use during categorization increased with increasing set coherence, suggesting that coherent training sets facilitate extraction of commonalities within a category. We conclude that learning from a coherent set of examples is an efficient means of forming abstract knowledge that generalizes broadly.

Learning to categorize perceptually similar stimuli can result in people becoming more sensitive to differences along perceptual dimensions that are relevant to category membership and/or less sensitive to equivalent differences along irrelevant perceptual dimensions. These effects of acquired distinctiveness and acquired equivalence may be caused by changes in the representations of stimuli which come about through adjustment to the relative attentional weighting of perceptual features or dimensions. Alternatively, the development of associations between individual stimuli and category labels could result in those labels being incorporated into the stimulus representation, hence increasing or decreasing generalization between the stimuli. For many categorization tasks, the expected effects of attentional weighting and associative mediation on stimulus similarity are the same. We report 3 experiments using complex category structures, which allowed us to assess the independent influence of each mechanism on stimulus similarity. The results suggest that, in these categorization tasks, attentional weighting affects perceptual similarity but associative mediation does not.

Generalization of learning can arise from 2 distinct sources: failure to discriminate a novel test stimulus from the trained stimulus and active extrapolation from the trained stimulus to the test stimulus despite them being discriminable. We investigated these 2 processes in a predictive learning task by testing stimulus discriminability (identification of the trained stimulus) as well as generalization of learning (outcome expectancy). Generalization gradients were broader for expectancy than for identification, in both single cue and differential (discrimination) designs, implying a substantial extrapolation component for the most dissimilar stimuli. The shapes of the expectancy gradients were strongly determined by the training design (single cue vs. differential) and by the rules inferred by participants (similarity vs. linear). By contrast, the identification gradients were unaffected by the training design or inferred rules and were equivalent for predictive and nonpredictive stimuli. These results indicate that perceptual discriminability plays a substantial role in generalization, but it is largely unaffected by associative learning. Instead, learning appears to impact on generalization via an independent extrapolation component which involves cognitive processes such as inductive reasoning.

In their seminal study of chess expertise, Simon and Chase (Chase & Simon, 1973; Simon & Chase, 1973) proposed that perceptual learning was a necessary component of skill acquisition. In their view, acquisition of skill results from the strategic use of learning at multiple levels to adaptively overcome inherent limitations. The knowledge acquired by way of perceptual learning that supported increasingly sophisticated perceptual discrimination processes, according to Simon and Chase, was referred to as a chunk. The chunk was conceptualized as a meaningful complex set of features that abstracted the notion of a perceptual object. Simon and Chase further suggested that meaningful combinations of chunks could be combined to form configurations (Simon & Chase, 1973, p. 399). The present study addresses this idea by framing the notion of a chunk in terms of two formal metatheories, one that addresses representation (Ashby & Townsend, 1986) and one that addresses processing (Townsend & Nozawa, 1995), and tests the prediction that perceptual learning produces organized perceptual objects (chunks). Two experiments combine behavioral and electroencephelographic (EEG) measures to show that perceptual learning produces (a) a shift from perceptual independence and separability to violations of separability, and (b) shifts from limited-capacity serial processing to supercapacity parallel processing. The evidence from both experiments is strong and consistent: perceptual learning does indeed induce chunking--the production of perceptual objects, and the foundation of perceptual expertise.

To learn a language infants must learn to link arbitrary sounds to their meaning. While words are the clearest example of this link, they are not the only component of language; morphological regularities (e.g., the plural -s suffix in English) carry meaning as well. Comprehensive theories of language acquisition must account for how infants build links between these other parts of language and their meaning. Here, we investigated the acquisition of morphology in infants learning Italian, a language with a rich inflectional morphology that marks both gender and number on both the article and final vowel of nouns. We demonstrate that infants can build these links between concepts and morphological regularities much earlier than previously thought. Italian-learning 12-18- and 24-month-olds were shown pairs of images of faces that differed either in number (1 female vs. 2 females; 1 male vs. 2 males) or gender (1 female vs. 1 male; 2 females vs. 2 males). On each trial infants were directed to look at one of the images with the morphological regularities as the only distinguishing cue. Overall, across all ages, the infants looked to the labeled image, indicating that they had at least some understanding of the morphology. While infants succeeded on both gender comparisons, they only showed evidence of understanding the feminine number distinction. These results indicate that in the early stages of language acquisition, infants are able to identify recurring morphemes and to map those morphological regularities to the concepts that they mark in the language.

The ability to discriminate social signals from faces is a fundamental component of human social interactions whose developmental origins are still debated. In this study, 5-year-old (N = 29) and 7-year-old children (N = 31) and adults (N = 34) made perceptual similarity and trustworthiness judgments on a set of female faces varying in level of expressed trustworthiness. All groups represented perceived similarity of the faces as a function of trustworthiness intensity, but such representation becomes more fine-grained with development. Moreover, 5-year-olds' accuracy in choosing the more trustworthy face in a pair varied as a function of children's score at the Test of Emotion Comprehension, suggesting that the ability to perform face-to-trait inferences is related to the development of emotional understanding.

Eyewitness researchers recommend that "not present" and "don't know" response options should be presented with police lineups. Although it is important that witnesses--most of whom are unlikely to be familiar with the identification task--are fully cognizant of all response options available to them, an understanding of how explicit non-identification options affect performance is lacking. Across four experiments, including 3,633 participants and 8 different stimulus sets, we tested the effects of including non-identification options in computer-administered lineups. When explicit non-identification options were presented, target-present and -absent choosing decreased. This decrease in choosing was characterized by a shift from filler identifications to lineup rejections. ROC analyses revealed that there was no overall difference in discriminability between guilty and innocent suspects depending on response option condition. On balance, the findings suggest that, in addition to informing witnesses about acceptable responses, displaying non-identification response options does not undermine identification performance.

According to the Diagnostic Feature-Detection (DFD) hypothesis, the presence of fillers that match the eyewitness's description of the perpetrator will boost discriminability beyond a showup, and very few fillers may suffice to produce the advantage. We tested this hypothesis by comparing showups with simultaneous lineups of size 3, 6, 9, and 12. Participants (N = 10,433) were randomly assigned to one of these conditions, as well as target-present (TP) versus target-absent (TA) lineup. As predicted by the DFD hypothesis, lineups were superior to showups, and there was no advantage with increased lineup size beyond a 3-member lineup. The confidence-accuracy (CA) relationship held a similar pattern. The only effect of increased lineup size was a lower likelihood of choosing a suspect (guilty or innocent). We conclude that police should focus more on the quality rather than quantity of fillers.

Here we report, for the first time, a relationship between sensitivity to amplitude envelope rise time in infants and their later vocabulary development. Recent research in auditory neuroscience has revealed that amplitude envelope rise time plays a mechanistic role in speech encoding. Accordingly, individual differences in infant discrimination of amplitude envelope rise times could be expected to relate to individual differences in language acquisition. A group of 50 infants taking part in a longitudinal study contributed rise time discrimination thresholds when aged 7 and 10 months, and their vocabulary development was measured at 3 years. Experimental measures of phonological sensitivity were also administered at 3 years. Linear mixed effect models taking rise time sensitivity as the dependent variable, and controlling for non-verbal IQ, showed significant predictive effects for vocabulary at 3 years, but not for the phonological sensitivity measures. The significant longitudinal relationship between amplitude envelope rise time discrimination and vocabulary development suggests that early rise time discrimination abilities have an impact on speech processing by infants.

Three source-memory experiments were conducted with Spanish-English bilinguals and monolingual English speakers matched on age, education, nonverbal cognitive ability and socioeconomic status. Bilingual language proficiency and dominance were assessed using standardized objective measures. In Experiment 1, source was manipulated visuo-spatially, in Experiment 2, source was manipulated temporally, and in Experiment 3, source was manipulated by presenting stimuli in different modalities. Bilingual source discrimination was more accurate for low-frequency words than for high-frequency words, but it did not differ for the more fluent and less fluent languages (L1 and L2, respectively). These results contrast with the L2 advantage observed in item recognition (Francis & Gutiérrez, 2012; Francis & Strobach, 2013), adding to evidence that the bases of performance for item and source memory differ. The dissociation of word frequency and language effects indicates that word-context associations are made at the conceptual level rather than the word-form level. Bilinguals exhibited more accurate source discrimination than monolinguals, both under intentional and incidental encoding conditions, indicating that this effect cannot be explained entirely by differences in encoding strategies. We reason that relative to monolinguals, bilinguals more efficiently encode associations between word concepts and contexts or other types of information that do not convey meaning preexperimentally. [Correction Notice: An Erratum for this article was reported in Vol 45(10) of "Journal of Experimental Psychology: Learning, Memory, and Cognition" (see record 2019-53018-001). In the article, a formula error in the scoring spreadsheet for bilingual participants in Experiment 3 systematically inflated their accuracy scores. Therefore, statistical information for analyses involving the bilingual sample, and bilingual portions of Table 7 and Figure 3 have been corrected. All versions of this article have been corrected.]

Many individuals with autism spectrum disorders (ASD) display stimulus overselectivity, wherein a subset of relevant components in a compound stimulus controls responding, which impairs discrimination learning. The original experimental research on stimulus overselectivity in ASD was conducted several decades ago; however, interventions for children with ASD now typically include programming to target conditional discriminations in ways that might minimize the prevalence of stimulus overselectivity. The present study assessed 42 children who had been diagnosed or educationally identified with ASD using a discrimination learning assessment. Of these 42 children, 19% displayed overselective responding, which is a lower percentage than that seen in early research. Possible explanations for this decreased percentage, implications for intervention, and future directions for research are discussed. [This paper was published in the "Journal of Applied Behavior Analysis" v48 n1 p71-84 Spr 2015 (EJ1053362).]

Most verbal behavior curricula for children with autism spectrum disorder (ASD) focus on teaching multiple mands during the early stages of training (e.g., picture exchange communication system; Bondy & Frost, 1994). However, few, if any, of those curricula train children with ASD to differentially mand only for reinforcers that are reasonable for a caregiver to deliver in a given context (e.g., mands to cuddle at bedtime) and to refrain from manding for reinforcers that would be inappropriate to deliver in that context (e.g., mands to play outside at bedtime). In this study, we first taught a boy with ASD two initial mands. Immediately thereafter we brought those mands under the conditional discriminative control of a four-component multiple schedule with (a) S[superscript 1] correlated with one reinforcer available (i.e., edibles), (b) S[superscript 2] correlated with both reinforcers available (i.e., edibles or drink), (c) S[superscript 3] correlated with another reinforcer available (i.e., drink), and (d) S[superscript delta] correlated with no reinforcer available. Following treatment, the child displayed conditionally discriminated manding in accordance with each of the four components of the schedule. We discuss these findings relative to the potential benefits of bringing mands under both evocative and discriminative control.

Interleaving examples of to-be-learned categories, rather than blocking examples by category, frequently enhances category induction. The presently dominant theory is that interleaving promotes discriminative-contrast, and suggests that category similarity structure modulates this interleaving benefit: that blocking should benefit learning when within-category similarity is low and that interleaving should benefit learning when between-category similarity is low. We test whether predictions of this hypothesis hold when generalized to real, complex categories artists' painting styles. Specifically, we test two predictions: (a) that within- and between-category structure should modulate the interleaving benefit (Exp 1a and 1b) and (b) that deliberately juxtaposing similar examples by different artists to highlight their key differences should improve learning (Exp 2a and 2b). We did not, however, find evidence that the discriminative-contrast hypothesis explains the interleaving benefit for complex, perceptual categories.

Introduction: This article describes the development and initial assessment of a set of tactile crayons that can produce different textured lines and areas on standard paper. Method: An assessment of the need for tactile crayons was performed through the use of surveys and focus groups from which a set of six tactile crayons was developed. Development was focused on being able to differentiate the crayons along the texture dimensions of sticky or slippery, rough or smooth, and hard or soft in informal dimensional analysis. Preliminary discrimination testing was performed to determine the viability of the six selected crayons. The main assessment determined whether individuals were able to identify each of the crayons by number from feeling scribbles on paper. Results: User needs assessment showed that many practitioners felt the development of tactile crayons would aid in teaching and fill a needs gap. The participants were able to discriminate the six crayons with a mean accuracy (standard error) of 77% (4%), and of those six, they could identify the four most easily discriminable with 86% (3%) accuracy. Discussion: Many families and teachers showed interest in the potential of tactile crayons as a learning tool. Four of the six tactile crayons were both highly discriminable and identifiable by adults who are visually impaired. This finding shows promise for discriminability and identifiability of these crayons by children who are visually impaired and their potential as a learning tool in both formal and informal learning environments. Implications for practitioners: The use of the developed tactile crayons has the potential to aid childhood development and student learning. In addition, the use of the crayons by teachers could help reduce the time needed to produce tactile diagrams.

The current study examined the effects of a brief mindfulness induction on overselectivity. Participants were randomly assigned to a mindfulness, unfocused attention (relaxation), or no-intervention group. Participants experienced their designated intervention for 10 min, and they underwent simultaneous discrimination training (AB+ CD-) followed by an extinction test (AvC, AvD, BvC, and BvD). Levels of mindfulness were measured by the Toronto Mindfulness Scale, and participants were asked about their previous experience with mediation and mindfulness practice. Mindfulness reduced overselectivity, and previous levels of mindfulness experience identified by a single question moderated this effect, with mindful-experienced participants showing less overselectivity. Both findings have some practical utility in the ongoing investigation of the possible use of mindfulness in medical settings.