Learning conceptual rules: III. Processes contributing to rule difficulty

Eight unique bidimensional conceptual rule forms were compared in a rule learning paradigm. It was predicted that rule difficulty order and error distributions across stimulus class defined by a truth table would be a function of Ss' preexperimental experience predominantly with conjunctive concepts. The hypothesis stated specifically that loci of difficulty with rules derive from: (a) assignment of TT stimuli (those with both relevant attributes) to the negative category; (b) assignment of FF stimuli (those with neither relevant attributes) to the positive category; (c) assignment of TT and FF stimuli to the same category. The main effects of rule and truth table class and the interaction of rule and truth table class were statistically significant. The results confirm all predictions about rule order and error distributions.     

Discriminating among diagnostic categories using the Dissociative Disorders Interview Schedule

The Dissociative Disorders Interview Schedule was administered to 1,308 subjects in eight diagnostic categories, including 296 with dissociative identity disorder. The study tested three hypotheses: (1) the Mahalanobis distance between dissociative identity disorder and each of seven other diagnostic categories would be large, (2) the closest diagnostic category to dissociative identity disorder would be dissociative disorder not otherwise specified, and (3) nondissociative diagnostic categories would be closer to each other than any one to dissociative identity disorder. All three hypotheses were confirmed by these data. The findings support the conclusion that dissociative identity disorder is a discrete category or taxon.     

Cognitive changes in conjunctive rule-based category learning: An ERP approach

When learning rule-based categories, sufficient cognitive resources are needed to test hypotheses, maintain the currently active rule in working memory, update rules after feedback, and to select a new rule if necessary. Prior research has demonstrated that conjunctive rules are more complex than unidimensional rules and place greater demands on executive functions like working memory. In our study, event-related potentials (ERPs) were recorded while participants performed a conjunctive rule-based category learning task with trial-by-trial feedback. In line with prior research, correct categorization responses resulted in a larger stimulus-locked late positive complex compared to incorrect responses, possibly indexing the updating of rule information in memory. Incorrect trials elicited a pronounced feedback-locked P300 elicited which suggested a disconnect between perception, and the rule-based strategy. We also examined the differential processing of stimuli that were able to be correctly classified by the suboptimal single-dimensional rule (“easy” stimuli) versus those that could only be correctly classified by the optimal, conjunctive rule (“difficult” stimuli). Among strong learners, a larger, late positive slow wave emerged for difficult compared with easy stimuli, suggesting differential processing of category items even though strong learners performed well on the conjunctive category set. Overall, the findings suggest that ERP combined with computational modelling can be used to better understand the cognitive processes involved in rule-based category learning.     

Processing controlled PROs in Spanish

Two experiments were carried out to investigate the processing of the empty category PRO and the time-course of this in Spanish. Eye movements were recorded while participants read sentences in which a matrix clause was followed by a subordinate infinitival clause, so that the subject or the object of the main clause could act as controller of PRO, and therefore as implicit grammatical subject of the infinitive. In Experiment 1, verb control information was manipulated: The matrix clause contained either subject-control verbs like prometer ('promise') or object-control verbs like forzar ('force'). In Experiment 2, the preposition that headed adverbial subordinate clauses was manipulated: Two different kinds of infinitival adverbial clauses were used, expressing purpose (preposition para) and reason (preposition por) and in which control information is primarily induced by the prepositions (para tends to trigger subject-control; por object-control). Experiment 1 showed that readers make immediate use of verb control information to recover the antecedent of the empty category PRO in Spanish obligatory control constructions. The data obtained in Experiment 2 suggest that during the processing of the empty category PRO in purpose vs. reason adverbial subordinate infinitival clauses the control information induced by the prepositions por vs. para is not initially used as a constraint to guide the selection of the nominal antecedent of PRO. In addition, both experiments showed that PRO antecedent selection is a very fast process and that, together with verb control information, recency played an important role. The results are discussed in terms of current psycholinguistic hypotheses about empty categories and in relation to formal linguistic hypotheses about PRO control. We argue that obligatory control ties (which are co-referential ties) are processed fast because they are launched from the same lexical platform that launches all fast syntactic connections (complements, as opposed to modifiers). In short, that such lexically-specified co-referential ties are regulated by linguistic form.     

Producing biased diagnoses with unambiguous stimuli: The importance of feature instantiations

In this article, the authors demonstrate a laboratory analogue of medical diagnostic biasing (V. R. LeBlanc, G. R. Norman, & L. R. Brooks, 2001) in 2 experiments and explore the basis of this effect. Before categorizing novel exemplars, participants first evaluated the likelihood that the item was a member of the category suggested on that trial: either the correct category or a plausible alternative category. This was sufficient to produce a substantial bias toward the suggested category despite the use of unambiguous stimuli, explicit rules, and unhurried conditions--each of which would be likely to limit diagnostic bias. The authors argue that the production of this effect requires distinguishing between particular feature instantiations and more abstract representations of those features as well as allowing people to adopt a particular decision strategy mediating the use of instantiated features: a feature-recognition heuristic.     

The inference of covert hypotheses by verbal reports in concept-learning research

A paradigm designed to examine the degree to which verbal reports represent the subject's learning was evaluated using a concept-acquisition task. Specifically, the degree to which hypotheses verbalized during the concept-acquisition procedure represent the covert hypotheses controlling category responding was examined. Subjects were required to make category responses, verbal reports, and sorts and re-sorts (blank-trial probes) of the stimuli at intervals in a reception paradigm. By comparing the sorts made during the acquisition procedure, the re-sorts after a 1-week delay, and the sorts made by subjects who had not participated in the acquisition procedure, it was determined that the verbal reports do not accurately represent the underlying hypothesis-testing process under all conditions. Verbal reports elicited at the beginning of the acquisition procedure and at criterion accurately represented the underlying hypotheses; those elicited at intervening points did not. The ambiguity of the verbal reports was a similar function of acquisition trials.     

Triadic decision making in lexical memory

Word and category recognition was investigated in the context of other stimuli, where the semantic distance relationships among the stimuli were derived from multidimensional scaling. On each trial, three horizontal strings of letters were presented. In the word condition, a positive response was required when the three strings formed three words; in the category condition, a positive response was required when the three strings formed words belonging to the same category. The results indicated that: (a) category decisions take about 150-200 msec longer than do word decisions, (b) word decisions are facilitated by a common categorical membership but semantic distances within the category are relatively unimportant, and (c)within-category semantic distances systematically altered response time for the category condition. It was hypothesized that semantic distance relationships may be sensitized for categorical decisions, but that only large semantic distances function effectively for word decisions.     

Incremental Bayesian Category Learning From Natural Language

Models of category learning have been extensively studied in cognitive science and primarily tested on perceptual abstractions or artificial stimuli. In this paper, we focus on categories acquired from natural language stimuli, that is, words (e.g., chair is a member of the furniture category). We present a Bayesian model that, unlike previous work, learns both categories and their features in a single process. We model category induction as two interrelated subproblems: (a) the acquisition of features that discriminate among categories, and (b) the grouping of concepts into categories based on those features. Our model learns categories incrementally using particle filters, a sequential Monte Carlo method commonly used for approximate probabilistic inference that sequentially integrates newly observed data and can be viewed as a plausible mechanism for human learning. Experimental results show that our incremental learner obtains meaningful categories which yield a closer fit to behavioral data compared to related models while at the same time acquiring features which characterize the learned categories. (An earlier version of this work was published in Frermann and Lapata 2014 .)     

The effects of feature necessity and extrinsicity on gradedness of category membership and class inclusion relations*

Two theories of differences among natural language categories in graded membership and strength of class inclusion are contrasted. The two sets of hypotheses tested were: (1) that categories represented by features which many people believe to be necessary would have less graded memberships, and stronger class inclusion, than those represented by features which few people believe to be necessary, and (2) that categories which people believe are represented primarily by intrinsic features (i.e. features that are true of an entity in isolation; see Barr & Caplan, 1987) would have less graded structures, and stronger class inclusion, than those which people believe are represented primarily by extrinsic features (i.e. features representing relations between an entity and other entities). The findings suggest that feature necessity and feature extrinsicity have independent effects on gradedness of category membership and on class inclusion.     

Naming and categorization in young children: IV: listener behavior training and transfer of function

Following pretraining with everyday objects, 14 children aged from 1 to 4 years were trained, for each of three pairs of different arbitrary wooden shapes (Set 1), to select one stimulus in response to the spoken word /zog/, and the other to /vek/. When given a test for the corresponding tacts ("zog" and "vek"), 10 children passed, showing that they had learned common names for the stimuli, and 4 failed. All children were trained to clap to one stimulus of Pair 1 and wave to the other. All those who named showed either transfer of the novel functions to the remaining two pairs of stimuli in Test 1, or novel function comprehension for all three pairs in Test 2, or both. Three of these children next participated in, and passed, category match-to-sample tests. In contrast, all 4 children who had learned only listener behavior failed both the category transfer and category match-to-sample tests. When 3 of them were next trained to name the stimuli, they passed the category transfer and (for the 2 subjects tested) category match-to-sample tests. Three children were next trained on the common listener relations with another set of arbitrary stimuli (Set 2); all succeeded on the tact and category tests with the Set 2 stimuli. Taken together with the findings from the other studies in the series, the present experiment shows that (a) common listener training also establishes the corresponding names in some but not all children, and (b) only children who learn common names categorize; all those who learn only listener behavior fail. This is good evidence in support of the naming account of categorization.     

A Latent Semantic Analysis of Gender Stereotype-Consistency and Narrowness in American English

Using latent semantic analysis, we examined gender stereotypes in American English by submitting over 100 masculine, neutral, and feminine role-words and trait-words to pair-wise semantic similarity comparisons with masculine (man, he, him) and feminine (woman, she, her) referents separately. We expected to find: (a) Stereotyping—roles and traits would be more semantically similar to the ostensible ‘matching’ than ‘mismatching’ gender category referent; (b) Categorical narrowness—both categories would be less semantically similar to counterstereotypical than to neutral or stereotypical characteristics; but this would be especially so for the male category, indicating its relatively greater narrowness. Results supported these hypotheses, but only among role-words. American English reflects and reinforces gender stereotypes regarding gender roles at a level beyond that recognized previously.     

Children's conceptions of characteristic features of category members

The authors investigated children's conceptions of the characteristic features of category members and found that their conceptions underwent qualitative developmental changes. They hypothesized that (a) children initially tend to perceive category members in terms of individual characteristics (i.e., internal dispositions and behavioral patterns) and (b) only later do they conceive of category members in terms of their shared beliefs and values. They explored these hypotheses in 2 studies: In Study 1, they investigated how Protestant and Catholic children in Northern Ireland understood the religious intergroup context in their own country; in Study 2, children in Italy were presented with a fictional scenario of intergroup conflict and asked to explain the causes of the conflict. The results of both studies confirmed the 2 hypotheses.     

A monte carlo evaluation of interactive multidimensional scaling

Interactive Scaling with Individual Subjects (ISIS) developed by Young & Cliff [1972], is a method involving interaction between subject and computer in real time to determine which judgments made by the subject are critical to the definition of a dimensional structure. The procedure is based on the mathematical fact that it is possible to define a space ofR dimensions in terms of only the interpoint distances between all stimuli being scaled and a subset of (R+1) of these stimuli. For errorless judgments, any subset of (R + 1) stimuli is appropriate. However, fallible data require that the subset consist of stimuli that are maximally dissimilar, and the ISIS procedure is designed to obtain such an optimum subset (a basis).This research evaluates a modified version of ISIS with respect to (a) a metric MDS analysis based on all possible pairs of the stimuli, and (b) a metric MDS analysis based on a subset of one-third of the possible pairs, or about the same number as that required by ISIS. Results show that the ISIS method achieves better fit than (b) at low error levels, and may also achieve better fit than (b) at higher error levels if the size of the basis is increased. The more stimuli in the basis the more indices of fit approach those of (a).A new method of introducing error in MDS studies is used in the evaluation.This research is based in part on the doctoral dissertation of the first author, and was supported by research grant MH-16474 from the National Institute of Mental Health, Public Health Service.     

Evolution and ontogeny of stress response to social challenges in the human child

The stress response systems of the human child are highly sensitive to social challenges. Because stress hormones can have negative developmental and health consequences, this presents an evolutionary paradox: Why would natural selection have favored mechanisms that elevate stress hormone levels in response to psychosocial stimuli? Two complementary hypotheses are considered: (a) maladaptation to the novelty of chronic stress in social environments, and (b) adaptive neural reorganization that facilitates the ontogeny of social competencies. Data on salivary cortisol, morbidity, and social environment from an 18 year study of child health in a rural community on the island of Dominica are examined from the perspective of these alternative hypotheses. Results indicate that difficult family environments and traumatic events are associated with elevated cortisol levels and higher morbidity. The long-term effects of traumatic early experiences on cortisol profiles are complex and indicate domain-specific effects, with normal recovery from physical stressors, but heightened response to negative-affect social challenges.     

Teaching children with autism spectrum disorder to tact olfactory stimuli

Research on tact acquisition by children with autism spectrum disorder (ASD) has often focused on teaching participants to tact visual stimuli. It is important to evaluate procedures for teaching tacts of nonvisual stimuli (e.g., olfactory, tactile). The purpose of the current study was to extend the literature on secondary target instruction and tact training by evaluating the effects of a discrete‐trial instruction procedure involving (a) echoic prompts, a constant prompt delay, and error correction for primary targets; (b) inclusion of secondary target stimuli in the consequent portion of learning trials; and (c) multiple exemplar training on the acquisition of item tacts of olfactory stimuli, emergence of category tacts of olfactory stimuli, generalization of category tacts, and emergence of category matching, with three children diagnosed with ASD. Results showed that all participants learned the item and category tacts following teaching, participants demonstrated generalization across category tacts, and category matching emerged for all participants.     

Children's Conceptions of Characteristic Features of Category Members

Abstract

The authors investigated children's conceptions of the characteristic features of category members and found that their conceptions underwent qualitative developmental changes. They hypothesized that (a) children initially tend to perceive category members in terms of individual characteristics (i.e., internal dispositions and behavioral patterns) and (b) only later do they conceive of category members in terms of their shared beliefs and values. They explored these hypotheses in 2 studies: In Study 1, they investigated how Protestant and Catholic children in Northern Ireland understood the religious intergroup context in their own country; in Study 2, children in Italy were presented with a fictional scenario of intergroup conflict and asked to explain the causes of the conflict. The results of both studies confirmed the 2 hypotheses.     

刺激材料的整体性知觉对类别建构的影响

采用标准－匹配的实验程序,操纵刺激材料的空间整合性和知觉的整体性水平,探讨逐个呈现刺激材料时影响被试类别建构策略的根本原因。报告了3个实验,结果证明：逐个呈现并不一定会导致被试倾向于家族相似性归类;刺激材料的空间整合性不一定会影响被试的类别建构策略,空间整合和空间分离都可能出现家族相似性和单维归类倾向;刺激材料的整体性知觉水平对类别建构影响明显：知觉为分离则倾向于家族相似性分类;知觉为整体则倾向于单维分类。被试在实验可能采用分析性策略,然而材料的整体性知觉影响了分析的侧重点,从而对类别建构产生了非常重要的影响     

The effect of the induction of involvement on psychophysical judgments

The present investigation was based on the concept of invariance, which holds that identical principles govern the judgment of stimuli arrayed on both physically and socially defined scales. Two experiments were conducted in which involvement was manipulated through the use of instructions presented in conjunction with category judgments obtained in a training session. This was followed by an anchor session. Experiment 1 employed a series of weights as stimuli, while Experiment 2 used random pattern dot slides. The experiments were similar, except for the inclusion of two additional features in the weight study. These were: (1) positive feedback, introduced as an independent variable between the judgment sessions and tested for its effect as an enhancer of involvement; and (2) two stimuli in the anchor session not part of the original stimulus series. These weights provided a test for the generality of involvement set. Among various hypotheses tested in both studies was the expectancy that the introduction of involvement associated with the formation of a judgment scale would lessen the impact of an anchor on judgment. This expectancy was based on the observed effects of involvement in social judgment contexts. Results of both experiments supported the judgment maintenance hypothesis.     

Using category structures to test iterated learning as a method for identifying inductive biases

Many of the problems studied in cognitive science are inductive problems, requiring people to evaluate hypotheses in the light of data. The key to solving these problems successfully is having the right inductive biases—assumptions about the world that make it possible to choose between hypotheses that are equally consistent with the observed data. This article explores a novel experimental method for identifying the biases that guide human inductive inferences. The idea behind this method is simple: This article uses the responses produced by a participant on one trial to generate the stimuli that either they or another participant will see on the next. A formal analysis of this "iterated learning" procedure, based on the assumption that the learners are Bayesian agents, predicts that it should reveal the inductive biases of these learners, as expressed in a prior probability distribution over hypotheses. This article presents a series of experiments using stimuli based on a well-studied set of category structures, demonstrating that iterated learning can be used to reveal the inductive biases of human learners.     

The commodified self in consumer culture: a cross-cultural perspective

The author examined the premise that the pervasive consumer ideology in today's society has implications for the conceptions of self and others. She used structured interviews to assess conceptions of self and other and G. P. Moschis's (1978) questionnaire to measure consumer orientation among 76 U.S. and 62 Finnish college students. The principal hypotheses were (a) that the U.S. students would be more commodified than the Finnish students and (b) that the participants who were high in consumer orientation would be more likely than those lower in consumer orientation to see themselves and others in material terms and also to consider personal characteristics to have market values. The results supported both hypotheses.