Variation among developmental dyslexics: evidence from a printed-word-learning task

A word-learning task was used to investigate variation among developmental dyslexics classified as phonological and surface dyslexics. Dyslexic children and chronological age (CA)- and reading level (RL)-matched normal readers were taught to pronounce novel nonsense words such as veep. Words were assigned either a regular (e.g., "veep") or an irregular (e.g., "vip") pronunciation. Phonological dyslexics learned both regular and exception words more slowly than the normal readers and, unlike the other groups, did not show a regular-word advantage. Surface dyslexics also learned regular and exception words more slowly than the CA group, consistent with a specific problem in mastering arbitrary item-specific pronunciations, but their performance resembled that of the RL group. The results parallel earlier findings from Manis, Seidenberg, Doi, McBride-Chang, & Petersen [Cognition 58 (1996) 157-195] indicating that surface dyslexics and phonological dyslexics have a different profile of reading deficits, with surface dyslexics resembling younger normal readers and phonological dyslexics showing a specific phonological deficit. Models of reading and reading disability need to account for the heterogeneity in reading processes among dyslexic children.     

中国文化下组织政治技能对个体自身的影响作用

组织政治技能是个体在组织中生存和获得职业发展的重要能力之一,也是组织行为学研究中的重要领域。研究主要从中国文化的视角,探讨组织政治技能对个体自身的影响作用。结果显示,组织政治技能与工作满意度之间存在线性关系,而非曲线关系;组织政治技能中的处世圆通和面子和谐两个维度有利于缓解工作压力,而人际敏锐可能增加个体的工作压力感;自我评价对于组织政治技能与工作压力和工作满意度之间关系的中介效应不显著;工作压力在处世圆通、人际敏锐和面子和谐三个维度与工作满意度之间起完全中介作用。这些结果表明,组织政治技能对于个体来说是非常重要的能力,可以帮助个体缓解工作压力,提高工作满意感,进而促进个体的职业发展。     

Reinforcement of vocalizations through contingent vocal imitation

Maternal vocal imitation of infant vocalizations is highly prevalent during face-to-face interactions of infants and their caregivers. Although maternal vocal imitation has been associated with later verbal development, its potentially reinforcing effect on infant vocalizations has not been explored experimentally. This study examined the reinforcing effect of maternal vocal imitation of infant vocalizations using a reversal probe BAB design. Eleven 3- to 8-month-old infants at high risk for developmental delays experienced contingent maternal vocal imitation during reinforcement conditions. Differential reinforcement of other behavior served as the control condition. The behavior of 10 infants showed evidence of a reinforcement effect. Results indicated that vocal imitations can serve to reinforce early infant vocalizations.     

Learning antecedents for anaphoric one

Lidz et al. [Lidz, J., Waxman, S., & Freedman, J. (2003). What infants know about syntax but couldn't have learned: Experimental evidence for syntactic structure at 18 months. Cognition, 89, B65-B73.] claim experimental substantiation of an argument from the poverty of the stimulus, in the sense of Pullum and Scholz [Linguist. Rev. 19 (2002) 9]. They cite a specific feature of English--the assignment of appropriate antecedents for anaphoric one--that cannot possibly be learned from experience because the evidence needed is found only in utterances of a type too rare to be encountered. Their argument involves three empirical claims. In this note we dispute all three.     

Uncovering the structure of a memorist's superior "basic" memory capacity

After extensive laboratory testing of the famous memorist Rajan, Thompson, Cowan, and Frieman (1993) proposed that he was innately endowed with a superior memory capacity for digits and letters and thus violated the hypothesis that exceptional memory fully reflects acquired "skilled memory." We successfully replicated the empirical phenomena that led them to their conclusions. From additional analyses and new experiments, we found support for an alternative hypothesis, namely that Rajan's superior memory for digits was mediated by learned encoding techniques that he acquired during nearly a thousand hours of practice memorizing the mathematical constant pi. Our paper describes a general experimental approach for studying the structure of exceptional memory and how Rajan's unique structure is consistent with the general theoretical framework of long-term working memory (Ericsson and Kintsch, 1995).     

Knowing letter names and learning letter sounds: a causal connection

Two experiments tested the common assumption that knowing the letter names helps children learn basic letter-sound (grapheme-phoneme) relation because most names contain the relevant sounds. In Experiment 1 (n=45), children in an experimental group learned English letter names for letter-like symbols. Some of these names contained the corresponding letter sounds, whereas others did not. Following training, children were taught the sounds of these same "letters." Control children learned the same six letters, but with meaningful real-word labels unrelated to the sounds learned in the criterion letter-sound phase. Differences between children in the experimental and control groups indicated that letter-name knowledge had a significant impact on letter-sound learning. Furthermore, letters with names containing the relevant sound facilitated letter-sound learning, but not letters with unrelated names. The benefit of letter-name knowledge was found to depend, in part, on skill at isolating phonemes in spoken syllables. A second experiment (n=20) replicated the name-to-sound facilitation effect with a new sample of kindergarteners who participated in a fully within-subject design in which all children learned meaningless pseudoword names for letters and with phoneme class equated across related and unrelated conditions.     

The effects of behavioral history on response acquisition with immediate and delayed reinforcement

Effects of prior exposure to the experimental chamber with levers present or absent and variable-time (VT) 60-s water deliveries arranged during one, five, or no 1-hr sessions were examined in rats during a 6-hr response-acquisition session in which presses on one lever produced water delivery immediately or after a 15-s resetting delay, and presses on the other lever canceled scheduled water deliveries. Response acquisition was (a) slower to occur when water deliveries were delayed, (b) most consistent in groups that had received five VT sessions, and (c) impaired by the presence of levers only when there had been five VT sessions and water deliveries were delayed during the acquisition session.     

Describing the Acquisition of Determiners in English: A Growth Modeling Approach

This paper, based on naturalistic data, describes the acquisitional course and use of the articles a and the in young English-speaking children (18-61 months), with special emphasis on the role of individual variation. A growth modeling approach to the data reveals that children's individual acquisition schedules are similar in trend, but vary in the rate at which they omit determiners at a given point of time. This picture suggests that an analysis that presumes homogeneous development will seriously misrepresent the fluctuations between and within individuals. Interestingly, this variation does not reflect a variation in children's abilities to use determiners correctly-irrespective of the rate in which they used determiners, children seldom used determiners incorrectly. The analysis also reveals that children's optional omission of determiners in obligatory contexts, beginning at 18 months of age, gradually decreases on average by 3-4% a month until 36 months of age, and thereafter plunges by a factor of 10 to an average of 0.3% per month. At 36 month of age the majority of children use determiners at a near-mastery level (Brown, 1973). These findings provide a useful framework for theorizing about possible mechanisms underlying the nature of early language development pre- and post-36 months of age.     

Learning Verbs Without Arguments: The Problem of Raising Verbs

This paper addresses the problem of learning the class of raising verbs (e.g. seem). These verbs are potentially problematic for learners in that unlike typical main verbs, these verbs do not stand in a semantic relation with any Noun Phrase (NP) arguments. Moreover, a second class of verbs, known as control verbs, shares certain distributional properties with raising verbs, but the two verb classes differ in important structural properties. The central problem addressed here is that of how a learner would distinguish raising verbs from control verbs, given their partial overlap in distribution. A series of experiments with English-speaking adults using a fill-in-the-blank questionnaire revealed two main types of cues that led participants to distinguish the two verb classes: inanimate NPs and semantically empty subjects (its raining) yielded the highest proportion of raising verb responses from adults, while animate NPs paired with eventive predicates yielded a high rate of control verb responses. On the basis of these results, suggestions are made as to how one should study the learning of these verbs in children.This research was supported by an NSF Postdoctoral Fellowship at the Institute for Research in Cognitive Science. I owe many, many thanks to Lila and Henry Gleitman, John Trueswell and the whole cast of participants in the Cheese seminar at IRCS during 2000–2002. In addition I would like to thank Ash Asudeh, Robin Clark, Jeffrey Lidz, Elliott Moreton, Julien Musolino, Anna Papafragou, Carson Schutze and an anonymous reviewer for comments and suggestions. I also thank audiences at University of North Carolina, University of Delaware, UCLA, Penn Linguistics Colloquium 26, Chicago Linguistic Society 38 and the CUNY Graduate Center for stimulating discussions. All errors and shortcomings are my own.