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This article proposes a neurobiological account of reading and reading disability suggesting that for normally developing readers, the dorsal (tempo-parietal) circuit predominates at first, and in conjunction with premotor systems, is associated with analytic processing necessary for learning to integrate orthographic with phonological and lexical-semantic features of printed words. The ventral (occipito-temporal) circuit underlies fluency in word recognition. (Contains references.) (Author/DB)

Converging evidence from a number of neuroimaging studies suggest that fluent word identification in reading is related to the functional integrity of two left hemisphere posterior systems: a temporo-parietal system and a ventral occipito-temporal system. Readers with difficulties demonstrate heightened reliance on both inferior frontal and right hemisphere posterior regions. (Contains references.) (Author/CR)

Statistical learning (SL) approaches to reading maintain that proficient reading requires assimilation of rich statistical regularities in the writing system. Reading skills in developing first-language readers are predicted by individual differences in sensitivity to regularities in mappings from orthography to phonology (O-P) and semantics (O-S), where good readers rely more on O-P consistency, and less on O-S associations. However, how these regularities are leveraged by second-language (L2) learners remains an open question. We utilize an individual-differences approach, measuring L2 English learners' sensitivity to O-P, O-S, and frequency during word-naming, across two years of immersion. We show that reliance on O-P is leveraged by better readers, while reliance on O-S is slower to develop, characterizing less proficient readers. All factors explain substantial individual variance in L2 reading skills. These findings show how SL plays a key role in L2 reading development through its role in assimilating sublexical regularities between print and speech. [ABSTRACT FROM AUTHOR]

Purpose: To examine neural response to spoken and printed language in children with speech sound errors (SSE). Method: Functional magnetic resonance imaging was used to compare processing of auditorily and visually presented words and pseudowords in 17 children with SSE, ages 8;6[years;months] through 10;10, with 17 matched controls. Results: When processing spoken words and pseudowords, the SSE group showed less activation than typically speaking controls in left middle temporal gyrus. They also showed greater activation than controls in several cortical and subcortical regions (e.g., left superior temporal gyrus, globus pallidus, insula, fusiform, and bilateral parietal regions). In response to printed words and pseudowords, children with SSE had greater activation than controls in regions including bilateral fusiform and anterior cingulate. Some differences were found in both speech and print processing that that may be associated with children with SSE failing to show common patterns of task-induced deactivation and/or attentional resource allocation. Conclusion: Compared with controls, children with SSE appear to rely more on several dorsal speech perception regions and less on ventral speech perception regions. When processing print, numerous regions were observed to be activated more for the SSE group than for controls. Key Words: functional magnetic resonance imaging (fMRI), speech sound errors, speech perception, print processing, Overt misarticulations (e.g., sound substitutions, omissions, and distortions) that persist into elementary school are associated with negative academic, social, and speech-language outcomes (Lewis & Freebairn, 1992; Nathan, Stackhouse, Goulandris, & [...]

This study linked 2 experimental paradigms for the analytic study of reading that heretofore have been used separately. Measures on a lexical decision task designed to isolate phono-logical effects in the identification of printed words were examined in young adults. The results were related to previously obtained measures of brain activation patterns for these participants derived from functional magnetic resonance imaging (fMRI). The fMRI measures were taken as the participants performed tasks that were designed to isolate orthographic, phonological, and lexical-semantic processes in reading. Individual differences in the magnitude of phonological effects in word recognition, as indicated by spelling-to-sound regularity effects on lexical decision latencies and by sensitivity to stimulus length effects, were strongly related to differences in the degree of hemispheric lateralization in 2 cortical regions.

In 3 visual word recognition experiments, the authors examined Ss' differential dependence on phonological versus orthographic information in accessing the lexicon. The critical manipulation was the presence or absence of pseudohomophones in the nonword context of a lexical decision task. Ss received a list with either no pseudohomophones (NPsH group) or 17%-30% pseudohomophones among the nonwords (PsH group). In the first 2 experiments Ss in the PsH group were faster and no less accurate on word trials than Ss in the NPsH group. Furthermore, performance in the NPsH group was adversely affected by phonological inconsistency in the target's orthographic neighborhood. In the final experiment, a double lexical decision paradigm was used, and performance on orthographically similar but phonologically dissimilar pairs differed in the 2 conditions.

A cohort model developed for visual word recognition assumes that the first orthographic word code activates the lexical entries in a manner consistent with the word's cohort. The model specifies graphic data and recodes it to an abstract orthographic format from which all lexical entries are resolved to a single protocol. The model involves a complex orthographic parameter called wickelgraph and enables a rapid resolution of the word by the user.

The role of a target's orthographic neighborhood in visual word recognition was investigated in 2 lexical decision experiments. In both experiments, some stimuli had 1 letter delayed relative to the presentation of the rest of the stimulus. Experiment 1 showed that delaying a letter position, which yielded a potentially competitive neighbor, was more costly to target recognition than delaying a position that yielded no neighbors. This effect was strongest when one of these neighbors was of higher frequency than the target itself. Additionally, the effect was reduced for words with a high friendly-to-unfriendly-neighbor ratio (friendly neighbors being those words containing the delayed letter). In Experiment 2 the difficulty of the word-nonword discrimination was manipulated by varying the density of the nonwords' neighborhoods. Only when the nonwords had many neighbors at several positions did the word responses show neighborhood competition effects.