Substitutability between conditioned and primary reinforcers in discrimination acquisition.

Rats and pigeons were trained on a series of reversals of a conditional simultaneous discrimination. The percentage of reinforcement for correct trials was varied across reversals. When nonreinforced correct trials produced the same feedback as incorrect trials, the number of errors to reach an acquisition criterion was greater for smaller percentages of reinforcement, but the number of reinforcers required was either approximately constant or smaller for the smaller percentages. When a stimulus paired with food (the conditioned reinforcer) was added on nonreinforced correct trials, both measures were substantially decreased. When the same stimulus was presented, but without a history of food pairing, learning rate was similar to when no stimulus was presented on nonreinforced trials. The results provide direct evidence that conditioned reinforcers may substitute, although imperfectly, for a primary reinforcer, and that pairing with the primary reinforcer is a necessary condition for such substitutability to occur.     

小学3～6年级儿童数运算策略的获得及策略应用无效性

研究采用实验室实验和心理测验的方法,选取小学3～6年级的120名儿童为被试,探讨了数运算过程中策略应用无效性是否存在以及儿童策略获得与发展的基本过程。结果发现:(1)在数运算的解题过程中存在策略应用无效性这一阶段;(2)儿童的认知成绩在策略学习前后基本上呈现为一种先下降后上升然后再下降的曲折模式,而不是简单的线性增长;(3)策略获得的过程包括策略探索、策略领会的初步运用和策略使用的退化三个阶段。     

听觉条件下词汇获得年龄效应产生机制的初探

通过三个实验考察听觉词汇的获得年龄效应。实验1采用基于语音的词汇判断任务,在错误率上存在词汇获得年龄效应,即早期习得词汇的正确率高于晚期习得词汇;实验2、3分别采用基于字形和语义的词汇判断任务,在反应时上存在词汇获得年龄效应,即早期习得词汇的反应快于晚期习得词汇。结果支持任意映射假说的观点：⒈词汇获得年龄效应产生于音、形、义加工的多个方面;⒉映射程度高低是决定词汇获得年龄效应大小的重要因素。     

Conceptual Factors Influence Children's Distributivity Bias

Sentences such as “The girls read a book” can lead to multiple interpretations: They could be reading the same book (collective) or they could each be reading their own book (distributive). In ambiguous contexts, adults prefer the collective interpretation, and preschool children show a slight bias for a distributive interpretation. The current research investigated whether conceptual factors (number of actors) influences interpretations of these kinds of predicates. The data with children show a stronger collective bias when there are four actors compared to two actors. This may be because children are more likely to conceptualize groups of four (vs. two) as sets rather than collections of individuals. These data are discussed with reference to research on visual and conceptual integration abilities, showing that children lag behind in their ability to combine components into a whole in comparison to parsing objects into their component parts.     

Effects of unit formation on the perception of a changing sound

The effects of subunit formation on adult listeners' ability to notice changes in a continuous spectral gradient of sound were studied. Results of this experiment support the idea that the auditory system processes information differently within a unit, and that this processing does not occur unless the perceptual system detects unit boundaries. In this experiment, silences were inserted into a continuously changing sound to cause the formation of short units. Listeners noticed the change earlier in conditions with silences inserted than in to conditions where the transition was either unbroken or broken by loud noise bursts. Results are discussed in terms of two processes, one that accentuates stimulus properties present at moments of onset and offset, and a second that uses onsets and offsets to signal the beginnings and ends of units and reduces the change perceived within units.     

Lending a hand to signed language acquisition: Enactment and iconicity enhance sign recall in hearing adult American Sign Language learners

Abstract

Evidence over the last 15 years has suggested that dual (imagery and verbal) coding explanations of concreteness effects in memory for word lists do not generalise well to memory for sentences and paragraphs. In contrast, an alternative framework based on relative differences in relational and distinctive processing has been shown to account for the effects of imagery and concreteness in these contexts and others. This paper describes recent research on free and cued recall of word lists and evaluates it with respect to the two models. The evidence suggests that whereas dual processing systems may be involved in the encoding of verbal materials, dual memory codes are insufficient to explain concreteness effects in recall. Better memory for high-as compared to low-imagery words depends on the use of paradigms that facilitate inter-item relational processing, independent of whether or not imagery is involved.     

Compositionality in a Parallel Architecture for Language Processing

Compositionality has been a central concept in linguistics and philosophy for decades, and it is increasingly prominent in many other areas of cognitive science. Its status, however, remains contentious. Here, I reassess the nature and scope of the principle of compositionality (Partee, 1995) from the perspective of psycholinguistics and cognitive neuroscience. First, I review classic arguments for compositionality and conclude that they fail to establish compositionality as a property of human language. Next, I state a new competence argument, acknowledging the fact that any competent user of a language L can assign to most expressions in L at least one meaning which is a function only of the meanings of the expression's parts and of its syntactic structure. I then discuss selected results from cognitive neuroscience, indicating that the human brain possesses the processing capacities presupposed by the competence argument. Finally, I outline a language processing architecture consistent with the neuroscience results, where semantic representations may be generated by a syntax-driven stream and by an “asyntactic” processing stream, jointly or independently. Compositionality is viewed as a constraint on computation in the former stream only.     

Labels and object categorization in six- and nine-month-olds: tracking labels across varying carrier phrases

Language shapes object categorization in infants. This starts as a general enhanced attentional effect of language, which narrows to a specific link between labels and categories by twelve months. The current experiments examined this narrowing effect by investigating when infants track a consistent label across varied input. Six-month-old infants (N = 48) were familiarized to category exemplars, each presented with the exact same labeling phrase or the same label in different phrases. Evidence of object categorization at test was only found with the same phrase, suggesting that infants were not tracking the label’s consistency, but rather that of the entire input. Nine-month-olds (N = 24) did show evidence of categorization across the varied phrases, suggesting that they were tracking the consistent label across the varied input.     

The Role of Animacy in Children's Interpretation of Relative Clauses in English: Evidence From Sentence–Picture Matching and Eye Movements

Subject relative clauses (SRCs) are typically processed more easily than object relative clauses (ORCs), but this difference is diminished by an inanimate head-noun in semantically non-reversible ORCs (“The book that the boy is reading”). In two eye-tracking experiments, we investigated the influence of animacy on online processing of semantically reversible SRCs and ORCs using lexically inanimate items that were perceptually animate due to motion (e.g., “Where is the tractor that the cow is chasing”). In Experiment 1, 48 children (aged 4;5–6;4) and 32 adults listened to sentences that varied in the lexical animacy of the NP1 head-noun (Animate/Inanimate) and relative clause (RC) type (SRC/ORC) with an animate NP2 while viewing two images depicting opposite actions. As expected, inanimate head-nouns facilitated the correct interpretation of ORCs in children; however, online data revealed children were more likely to anticipate an SRC as the RC unfolded when an inanimate head-noun was used, suggesting processing was sensitive to perceptual animacy. In Experiment 2, we repeated our design with inanimate (rather than animate) NP2s (e.g., “where is the tractor that the car is following”) to investigate whether our online findings were due to increased visual surprisal at an inanimate as agent, or to similarity-based interference. We again found greater anticipation for an SRC in the inanimate condition, supporting our surprisal hypothesis. Across the experiments, offline measures show that lexical animacy influenced children's interpretation of ORCs, whereas online measures reveal that as RCs unfolded, children were sensitive to the perceptual animacy of lexically inanimate NPs, which was not reflected in the offline data. Overall measures of syntactic comprehension, inhibitory control, and verbal short-term memory and working memory were not predictive of children's accuracy in RC interpretation, with the exception of a positive correlation with a standardized measure of syntactic comprehension in Experiment 1.