Previous studies have shown that the effect of language on categorical perception of color is stronger when stimuli are presented in the right visual field than in the left. To examine whether this lateralized effect occurs preattentively at an early stage of processing, we monitored the visual mismatch negativity, which is a component of the event-related potential of the brain to an unfamiliar stimulus among a temporally presented series of stimuli. In the oddball paradigm we used, the deviant stimuli were unrelated to the explicit task. A significant interaction between color-pair type (within-category vs. between-category) and visual field (left vs. right) was found. The amplitude of the visual mismatch negativity component evoked by the within-category deviant was significantly smaller than that evoked by the between-category deviant when displayed in the right visual field, but no such difference was observed for the left visual field. This result constitutes electroencephalographic evidence that the lateralized Whorf effect per se occurs out of awareness and at an early stage of processing.lateralization | Whorfian B ehavioral, electrophysiological, and neuroimaging studies have shown that early processing of color stimuli can be affected by the categories encoded in the language of the observer (1-13). More recently, this "Whorfian" effect in color processing has been demonstrated to be stronger for stimuli exposed in the right visual field (RVF) than in the left visual field (LVF) and to disappear in the presence of a concurrent demand on verbal memory. This finding suggests that the use of lexical information in the left hemisphere is the origin of differential visual hemifield responses to color stimuli (14-23). There has been some suggestion that the left cerebral hemispheric areas implicated in important language functions may serve as a top-down control source that modulates the activity level of the visual cortex (24-28), but little is known about whether this lateralized effect occurs at early, preattentive perceptual processing stages or at postperceptual decision/response phases. Visual mismatch negativity (vMMN) is widely held to reflect the brain's early and automatic change in event-related potentials (ERPs) in response to a novel stimulus (29)(30)(31). In the present study, the vMMN component is observed in order to assess the lateralized Whorfian response to task-irrelevant changes in color stimuli. There have been several related studies in this area, however. Thierry and associates (25,26) showed in nonlateralized studies with task-irrelevant responses that Greek speakers' vMMN components, starting around 100 ms poststimulus, peaking around 200 ms, and maximal over parietooccipital scalp areas, show sensitivity to the basic lexical distinction in the Greek language between light and dark blue, whereas English speakers show no such effect. Further ERP studies have confirmed early Whorfian effects in nonlateralized paradigms (27,28). [Fonteneau and Davidoff (12) were the first to show a n...

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Developmental differences in phonological and orthographic processing in Chinese were examined in 9 year olds, 11 year olds, and adults using functional magnetic resonance imaging. Rhyming and spelling judgments were made to 2-character words presented sequentially in the visual modality. The spelling task showed greater activation than the rhyming task in right superior parietal lobule and right inferior temporal gyrus, and there were developmental increases across tasks bilaterally in these regions in addition to bilateral occipital cortex, suggesting increased involvement over age on visuo-orthographic analysis. The rhyming task showed greater activation than the spelling task in left superior temporal gyrus and there were developmental decreases across tasks in this region, suggesting reduced involvement over age on phonological representations. The rhyming and spelling tasks included words with conflicting orthographic and phonological information (i.e., rhyming words spelled differently or nonrhyming words spelled similarly) or nonconflicting information. There was a developmental increase in the difference between conflicting and nonconflicting words in left inferior parietal lobule, suggesting greater engagement of systems for mapping between orthographic and phonological representations. Finally, there were developmental increases across tasks in an anterior (Broadman area [BA] 45, 46) and posterior (BA 9) left inferior frontal gyrus, suggesting greater reliance on controlled retrieval and selection of posterior lexical representations.

MBCT may be a useful intervention for college students with ADHD, improving participants' ADHD symptoms, mindfulness, and sustained attention.

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