The formation of a generalized categorization repertoire: effect of training with multiple domains,samples, and comparisons

The present experiment explored the effects of three variables on the spontaneous categorization of stimuli in perceptually distinct and novel domains. Each of six stimulus domains was created by morphing two images that were the domain endpoints. The endpoints of the domains were male and female faces, two abstract drawings, a car and a truck, two banded-elevation satellite land images, a tree and a cat, and two false-color satellite images. The stimulus variants at each end of a domain defined two potential perceptual classes. Training was conducted in a matching-to-sample format and used stimuli from one or two domains, one or three variants per class as samples, and one or three variants per class as comparisons. The spontaneous categorization of stimuli in the untrained stimulus domains showed the emergence of a generalized categorization repertoire. The proportion of spontaneously categorized stimuli in the new domains was positively related to the number of domains and samples used in training, and was inversely related to the number of comparisons used in training. Differential reaction times demonstrated the discriminability of the stimuli in the emergent classes. This study is among the first to provide an empirical basis for a behavior-analytic model of the development of generalized categorization repertoires in natural settings.     

Sex differences in judgement of facial affect: a multivariate analysis of recognition errors

The present paper investigated recognition errors in affective judgement of facial emotional expressions. Twenty-eight females and sixteen males participated in the study. The results showed that in both males and females emotional displays could be correctly classified, but females had a higher rate of correct classification; males were more likely to have difficulty distinguishing one emotion from another. Females rated emotions identically regardless of whether the emotion was displayed by a male or female face. Furthermore, the two-factor structure of emotion, based on a valence and an arousal dimension, was only present for female subjects. These results further extend our knowledge about gender differences in affective information processing.     

Infants' formation and use of categories to segregate objects

Four- and-a-half-month-old infants' (N = 100) category formation and use was studied in a series of five experiments. For each experiment, the test events featured a display composed of a cylinder and a box. Previous research showed that this display is not clearly parsed as a single unit or as two separate units by infants of this age. Immediately prior to testing, infants were shown a set of category exemplars. Knowledge about this category could help infants disambiguate the test display, which contained a novel exemplar of this category. Clear interpretation of the test display as composed of two separate units (as indicated by infants' longer looking at the move-together than at the move-apart test event) was taken as evidence of category formation and use. In Experiments 1 and 5, infants' prior experience with a set of three different boxes that were similar to the test box facilitated their segregation of the test display. Experiment 2 showed that three different exemplars are necessary: prior experience with any two of the three boxes used in Experiment 1 did not facilitate infants' segregation of the test display. Experiment 3 showed that variability in the exemplar set is necessary: prior experience with three identical boxes did not facilitate infants' segregation of the test display. Experiment 4 showed that under these conditions of very brief prior exposure, similarity between the exemplar set and test box is necessary: prior experience with three different boxes that were not very similar to the test box did not facilitate infants' segregation of the test display. Together, these findings suggest that: (a) number of exemplars, variability, and similarity in the exemplar set are important for infants' category formation, and (b) infants use their category knowledge to determine the boundaries of the objects in a display.     

Facilitative orthographic neighborhood effects: the SERIOL model account

A large orthographic neighborhood (N) facilitates lexical decision for central and left visual field/right hemisphere (LVF/RH) presentation, but not for right visual field/left hemisphere (RVF/LH) presentation. Based on the SERIOL model of letter-position encoding, this asymmetric N effect is explained by differential activation patterns at the orthographic level. This analysis implies that it should be possible to negate the LVF/RH N effect and create an RVF/LH N effect by manipulating contrast levels in specific ways. In Experiment 1, these predictions were confirmed. In Experiment 2, we eliminated the N effect for both LVF/RH and central presentation. These results indicate that the letter level is the primary locus of the N effect under lexical decision, and that the hemispheric specificity of the N effect does not reflect differential processing at the lexical level.     

Determinants of capacious memory: a process-dissociation and experiential approach

The aim of this study is to delineate some important circumstances where exceptionally good memory performance, or capacious memory occurs. A further aim is to study memory processes involved in this memory phenomenon. In a first experiment, participants looked through two series of pictures differing in number and were evaluated in two-alternative forced-choice and yes-no recognition memory tasks combined in a process-dissociation procedure. Moreover, participants were asked to provide remember and know responses to tap recollective experience. The results as to forced-choice recognition task accuracy and according to process-dissociation procedure estimates were replicated in a second experiment with a more intrinsic contextual manipulation, and in a third, forgetting experiment. In addition to replicating previous findings, the results show (a) that capacious memory is associated with strong feelings of recollection; and (b) that familiarity (in terms of the process-dissociation framework) contributes to this phenomenon.     

Spoken Idiom Recognition: Meaning Retrieval and Word Expectancy

This study investigates recognition of spoken idioms occurring in neutral contexts. Experiment 1 showed that both predictable and non-predictable idiom meanings are available at string offset. Yet, only predictable idiom meanings are active halfway through a string and remain active after the string’s literal conclusion. Experiment 2 showed that the initial fragment of a predictable idiom inhibits recognition of a word providing a congruous, but literal, conclusion to the expression. No comparable effects were obtained with non-predictable idioms. These findings are consistent with the view that spoken idiom identification differs from word recognition and occurs word-by-word, just as with other familiar, multi-lexical phrases.The present study was supported by PRIN 2003–2004. We would like to thank Corrado Cavallero, Simona Collina, Melinda Tucker and Francesco Zardon for their valuable help.     

Comprehending Semantic and Grammatical Violations in Italian. N400 and P600 Comparison with Visual and Auditory Stimuli

Arguments about the existence of language-specific neural systems and specifically about the independence of syntactic and semantic processing have focused on the event-related brain measures (ERPs) as tool to monitoring moment-by-moment the cognitive processes underlaid. In the present experiments, the available evidence indicates that the ERP response to semantic anomalies is at least partially distinct from the ERP response to syntactic anomalies and that two distinct processes are activated in sentences comprehension. ERPs were recorded from 10 electrodes while subjects read (Experiment 1) or listened (Experiment 2) to sentences containing semantic or syntactic violations. Final-words that were inconsistent with the sentence context elicited a negative-going wave at about 400 ms poststimulus, whereas penultimate-word incongruous with the grammatical structure (subject–verb non-agreement) elicited a positive-going wave about 600 ms poststimulus. No differences based on the perceptual modality of the stimulus (visual or auditory) nor different ERP correlates as a function of task-relevance (explicit/implicit task induction) were found. The implications of our results for Italian language are explained.     

Conceptual versus Perceptual Priming in Incomplete Picture Identification

This paper examined conceptual versus perceptual priming in identification of incomplete pictures by using a short-term priming paradigm, in which information that may be useful in identifying a fragmented target is presented just prior to the target’s presentation. The target was a picture that slowly and continuously became complete and the participants were required to press a key as soon as they knew what it was. Each target was preceded by a visual prime. The nature of this prime varied from very conceptual (e.g., the name of the picture’s category) to very perceptual (e.g., a similar-shaped pictorial prime from a different category). Primes also included those that combined perceptual and conceptual information (e.g., names or images of the target picture). Across three experiments, conceptual primes were effective while the purely perceptual primes were not. Accordingly, we conclude that pictures in this type of task are identified primarily by conceptual processing, with perceptual processing contributing relatively little.     

How Should a Speech Recognizer Work?

Although researchers studying human speech recognition (HSR) and automatic speech recognition (ASR) share a common interest in how information processing systems (human or machine) recognize spoken language, there is little communication between the two disciplines. We suggest that this lack of communication follows largely from the fact that research in these related fields has focused on the mechanics of how speech can be recognized. In Marr's (1982) terms, emphasis has been on the algorithmic and implementational levels rather than on the computational level. In this article, we provide a computational-level analysis of the task of speech recognition, which reveals the close parallels between research concerned with HSR and ASR. We illustrate this relation by presenting a new computational model of human spoken-word recognition, built using techniques from the field of ASR that, in contrast to current existing models of HSR, recognizes words from real speech input.     

自我面孔识别的独特性

与识别他人的面孔相比,自我面孔识别在行为反应、种系发生、个体发展以及脑机制等方面都具有很大的独特性。行为指标方面,自我面孔识别在速度上快于识别他人的面孔;种系发生方面,只有人类和大猩猩等高级灵长类动物才具有识别自己面孔的能力;个体发展方面,儿童出生后不久即能识别他人面孔,但要在18个月左右才能表现出自我面孔识别能力;脑机制方面,神经心理学和脑成像研究结果表明自我面孔识别可能主要是右脑的功能。该领域的研究进展将为深入了解自我的形成机理提供一个新的探视“窗口”。