Labels as features (not names) for infant categorization: a neurocomputational approach

A substantial body of experimental evidence has demonstrated that labels have an impact on infant categorization processes. Yet little is known regarding the nature of the mechanisms by which this effect is achieved. We distinguish between two competing accounts: supervised name-based categorization and unsupervised feature-based categorization. We describe a neurocomputational model of infant visual categorization, based on self-organizing maps, that implements the unsupervised feature-based approach. The model successfully reproduces experiments demonstrating the impact of labeling on infant visual categorization reported in Plunkett, Hu, and Cohen (2008) . It mimics infant behavior in both the familiarization and testing phases of the procedure, using a training regime that involves only single presentations of each stimulus and using just 24 participant networks per experiment. The model predicts that the observed behavior in infants is due to a transient form of learning that might lead to the emergence of hierarchically organized categorical structure and that the impact of labels on categorization is influenced by the perceived similarity and the sequence in which the objects are presented. The results suggest that early in development, say before 12 months old, labels need not act as invitations to form categories nor highlight the commonalities between objects, but they may play a more mundane but nevertheless powerful role as additional features that are processed in the same fashion as other features that characterize objects and object categories.     

工作记忆中的词长效应

工作记忆中的词长效应是指在即时序列回忆中短单词列的成绩优于长单词列的现象。该文首先回顾与词长效应有关的实验研究及阐述对应的理论解释,包括经典的语音回路理论和新近提出的特征模型、整合理论、项目位置权衡理论和SIMPLE理论等,然后介绍在这一方面运用脑成像技术研究的进展,如ERP,PET和fMRI方面的研究,为词长效应理论解释提供了进一步的证据,接着讨论词长效应研究中存在的争议,最后简评各主要理论并展望了今后研究的趋势     

Phonological Activation in Multi-syllabic Sord Recognition

Three experiments were conducted to test the phonological recoding hypothesis in visual word recognition. Most studies on this issue have been conducted using mono-syllabic words, eventually constructing various models of phonological processing. Yet in many languages including English, the majority of words are multi-syllabic words. English includes words incorporating a silent letter in their letter strings (e.g., champane). Such words provide an opportunity for investigating the role of phonological information in multi-syllabic words by comparing them to words that do not have the silent letter in the corresponding position (e.g., passener). The performance focus is on the effects of removing letters from words with a silent letter and from words with a non-silent letter. Three representative lexical tasks—naming, semantic categorization, lexical decision—were conducted in the present study. Stimuli that excluded a silent letter (e.g., champa_ne) were processed faster than those that excluded a sounding letter (e.g., passen_er) in the naming (Experiment 1), the semantic categorization (Experiment 2), and the lexical decision task (Experiment 3). The convergent evidence from these three experiments provides seminal proof of phonological recoding in multi-syllabic word recognition. An erratum to this article can be found at     

Words, hemispheres, and processing mechanisms: A response to Marsolek and Deason (2007)

Ellis, Ansorge and Lavidor (2007) [Ellis, A.W., Ansorge, L., & Lavidor, M. (2007). Words, hemispheres, and dissociable subsystems: The effects of exposure duration, case alternation, priming and continuity of form on word recognition in the left and right visual fields. Brain and Language, 103, 292–303.] presented three experiments investigating the effects of exposure duration and format (normal vs mixed or alternating case) on the recognition of words presented in the left and right visual fields. The experiments were conducted within the framework of ‘dissociable neural subsystems theory’ developed by Marsolek and colleagues. Marsolek and Deason (2007) [Marsolek, C.J. & Deason, R.G. (2007). Hemispheric asymmetries in visual word-form processing: Progress, conflict, and evaluating theories. Brain and Language, 103, 304–307.] offer some reflections on our paper, including alternative interpretations of some of our findings. We respond to those reflections in this reply.     

Reproducibility and a unifying explanation: Lessons from the shape bias

The goal of science is to advance our understanding of particular phenomena. However, in the field of development, the phenomena of interest are complex, multifaceted, and change over time. Here, we use three decades of research on the shape bias to argue that while replication is clearly an important part of the scientific process, integration across the findings of many studies that include variations in procedure is also critical to create a coherent understanding of the thoughts and behaviors of young children. The “shape bias,” or the tendency to generalize a novel label to novel objects of the same shape, is a reliable and robust behavioral finding and has been shown to predict future vocabulary growth and possible language disorders. Despite the robustness of the phenomenon, the way in which the shape bias is defined and tested has varied across studies and laboratories. The current review argues that differences in performance that come from even seemingly minor changes to the participants or task can offer critical insight to underlying mechanisms, and that working to incorporate data from multiple labs is an important way to reveal how task variation and a child’s individual pathway creates behavior—a key issue for understanding developmental phenomena.     

A methodological investigation of the Intermodal Preferential Looking paradigm: Methods of analyses,picture selection and data rejection criteria

The Intermodal Preferential Looking paradigm provides a sensitive measure of a child's online word comprehension. To complement existing recommendations (Fernald, Zangl, Portillo, & Marchman, 2008), the present study evaluates the impact of experimental noise generated by two aspects of the visual stimuli on the robustness of familiar word recognition with and without mispronunciations: the presence of a central fixation point and the level of visual noise in the pictures (as measured by luminance saliency). Twenty-month-old infants were presented with a classic word recognition IPL procedure in 3 conditions: without a fixation stimulus (No Fixation – noisiest condition), with a fixation stimulus before trial onset (Fixation, intermediate), and with a fixation stimulus, a neutral background and equally salient images (Fixation Plus – least noisy). Data were systematically analyzed considering a range of data selection criteria and dependent variables (proportion of looking time towards the target, longest look, and time-course analysis). Critically, the expected pronunciation and naming interaction was only found in the Fixation Plus condition. We discuss the impact of data selection criteria and the dependent variable choice on the modulation of these effects across the different conditions.     

Projection of a binary criterion into a model of hierarchical classes

A formal analysis is made of how to project an attribute criterion into the hierarchical classes model for object by attribute data proposed by De Boeck and Rosenberg. The projection is conceptualized as the prediction of the attribute criterion by means of a logical rule defined on the basis of attribute combinations from the model. Eliminative and constructive strategies are proposed to find logical rules with maximal predictive power and minimal formula complexity. Logical analyses of a real data set are reported and compared with a logistic regression to demonstrate the usefulness of the logical strategies, and to show the complementarity of logical and probabilistic approaches.The first suthor is Senior Research Assistant of the National Fund for Scientific Research (Belgium). We would like to thank the Editor, the reviewers, Seymour Rosenberg, and Luc Delbeke for their helpful comments on earlier drafts of this article.     

BELIEFS OF A CHRISTIAN MINISTER IN LIGHT OF CONTEMPORARY SCIENCE

Abstract. This paper states the author's understanding of the doctrines of the Christian faith in the light of her scientific background and her interpretation of current evolutionary, neuropsychologi–cal, and other scientific theories. It contains the actual ordination vows and her response to them, based upon an outline of questions suggested by the United Church of Christ.     

学龄早期词语阅读习得对阅读理解能力的预测作用：初始水平和发展速率的贡献

本研究测查了183名儿童在一年级期间（学年初,学年中,学年末）的词语阅读能力（词语解码,阅读流畅性）及一年级末和二年级末的阅读理解能力,采用分层线性模型估计每名儿童在一年级期间词语阅读能力的初始水平和发展速率,以考察二者对阅读理解能力的独立预测作用。结果表明,词语识别的初始水平和增长速率都能独立预测一年级末和二年级末的阅读理解能力,阅读流畅性的初始水平和增长速率只能独立预测二年级末的阅读理解能力,但可以预测阅读理解能力在一年级到二年级的增长。