Article

Two distinct forms of functional lateralization in the human brain

Section on Cognitive Neuropsychology, Laboratory of Brain and Cognition, and Scientific and Statistical Computing Core, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 08/2013; 110(36). DOI: 10.1073/pnas.1302581110
Source: PubMed

ABSTRACT The hemispheric lateralization of certain faculties in the human brain has long been held to be beneficial for functioning. However, quantitative relationships between the degree of lateralization in particular brain regions and the level of functioning have yet to be established. Here we demonstrate that two distinct forms of functional lateralization are present in the left vs. the right cerebral hemisphere, with the left hemisphere showing a preference to interact more exclusively with itself, particularly for cortical regions involved in language and fine motor coordination. In contrast, right-hemisphere cortical regions involved in visuospatial and attentional processing interact in a more integrative fashion with both hemispheres. The degree of lateralization present in these distinct systems selectively predicted behavioral measures of verbal and visuospatial ability, providing direct evidence that lateralization is associated with enhanced cognitive ability.

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Available from: Stephen J. Gotts, Jul 08, 2015
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    • "In older children and in adults, the degree of lateralization might be related to some measures of cognitive abilities (e.g. Gotts et al., 2013): for example, the most important deficits in academic abilities assessed in 11-year olds were found in individuals with equal motor skills in the two hands (Cheyne, Roberts, Crow, Leask, & Garcia-Finana, 2010). Moreover, left-handedness may facilitate the performance of cognitive tasks requiring greater engagement of right-hemisphere resources, such as visuospatial tasks (e.g. "
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    • "In older children and in adults, the degree of lateralization might be related to some measures of cognitive abilities (e.g. Gotts et al., 2013): for example, the most important deficits in academic abilities assessed in 11-year olds were found in individuals with equal motor skills in the two hands (Cheyne, Roberts, Crow, Leask, & Garcia-Finana, 2010). Moreover, left-handedness may facilitate the performance of cognitive tasks requiring greater engagement of right-hemisphere resources, such as visuospatial tasks (e.g. "
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