B. Butterworth

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Thirty-one 8- and 9-year-old children selected for dyscalculia, reading difficulties or both, were compared to controls on a range of basic number processing tasks. Children with dyscalculia only had impaired performance on the tasks despite high-average performance on tests of IQ, vocabulary and working memory tasks. Children with reading disability were(More)
In this study we investigated the acalculic condition of a patient, C.G., with the classical signs of Gerstmann's Syndrome: finger agnosia; right-left disorientation; a profound agraphia (but with an equally profound alexia) and a remarkably dense acalculia. Using a series of number processing and number knowledge tasks, a selective impairment for numbers(More)
McNeill (1985) claimed that speech and its accompanying gestures "share a common computational stage" that is located early in the speech production process. This position depends on two crucial arguments that we believe are unsound: first, that gestures "are synchronized with linguistic units in speech" and, second, that gestures "have semantic and(More)
Use of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxicity equivalents concentration (TEC) assumes that polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) act additively and via a common mechanism to cause toxicity. To test these assumptions, 11 TCDD-like congeners and three non-TCDD-like congeners were combined at ratios(More)
Severe difficulties in learning about numbers and arithmetic are probably as widespread as disorders of literacy development (dyslexia). The best prevalence estimates for each lie between 3.6% and 6.5% (see Table 26.1). Studies in the U.K. have revealed that poor mathematical skills are more of a handicap in the workplace than poor literacy skills (Bynner &(More)
A short-term reproduction assay with the fathead minnow (Pimephales promelas) has been developed to detect chemicals with the potential to disrupt reproductive endocrine function controlled by estrogen- and androgen-mediated pathways. The objective of this study was to use the assay to characterize responses of fathead minnow reproductive endocrinology and(More)
Techniques of hesitation analysis taken from studies of normal speakers were applied to the speech of a jargon aphasic. Neologisms were found to follow pauses indicating a word-finding difficulty. Other language functions-phonology, morphology, and syntax-appeared unimpaired, and further analyses of the linguistic and temporal characteristics indicated a(More)
This paper reports studies of subject-verb agreement errors with speakers of Spanish and English; we used a sentence completion task, first introduced by Bock and Miller (1991). In a series of four experiments, we assessed the role of semantic information carried by the sentential subject in the induction of subject-verb agreement errors. For Spanish(More)
© 1996 Psychology Press, an imprint of Erlbaum (UK) Taylor & Francis Ltd. Requests for reprints should be sent to David C. Geary, Department of Psychology, 210 McAlester Hall, University of Missouri, Columbia, MO 65211, USA. I would like to thank Christy Bow-Thomas, Jennifer Mueller, Mary O’Brien, Liu Fan, and Mary Hoard for their assistance with data(More)
We report the case of AS, a 16 year-old English/Japanese bilingual boy, whose reading/writing difficulties are confined to English only. AS was born in Japan to a highly literate Australian father and English mother, and goes to a Japanese selective senior high school in Japan. His spoken language at home is English. AS's reading in logographic Japanese(More)