A role for the “magnocellular advantage” in visual impairments in neurodevelopmental and psychiatric disorders

School of Psychological Science, La Trobe University, Bunndoora, Vic. 3086, Australia.
Neuroscience & Biobehavioral Reviews (Impact Factor: 8.8). 02/2007; 31(3):363-76. DOI: 10.1016/j.neubiorev.2006.10.003
Source: PubMed


Evidence exists implicating abnormal visual information processing and visually driven attention in a number of neurodevelopmental and psychiatric disorders, suggesting that research into such disorders may benefit from a better understanding of more recent advances in visual system processing. A new integrated model of visual processing based on primate single cell and human electrophysiology may provide a framework, to understand how the visual system is involved, by implicating the magnocellular pathway's role in driving attentional mechanisms in higher-order cortical regions, what we term the 'magnocellular advantage'. Evidence is also presented demonstrating visual processing occurs considerably faster than previously assumed, and emphasising the importance of top-down feedback signals into primary visual cortex, as well as considering the possibility of lateral connections from dorsal to ventral visual areas. Such organisation is argued to be important for future research highlighting visual aspects of impairment in disorders as diverse as schizophrenia and autism.

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Available from: Sheila Crewther, Jan 02, 2015
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    • "Using LORETA, we first localized the origin of the P1 potential (collapsed across the three emotions) to the extrastriate cortex for HSF images [cuneus/BA 18, MNI coordinates: peak x, y, 100 z ¼ À24, À102, À6] and to the postcentral gyrus in the parietal lobe for LSF images (peak x, y, z ¼ 18, À53, 71; Supplementary Figure S1). In support of our ERP extraction and source localization , these source results concurred with the asymmetry of the ventral vs dorsal visual stream that HSF vs LSF information pref- 105 erentially activates, respectively (De Valois et al., 1982; Livingstone and Hubel, 1988; Merigan and Maunsell, 1993; Laycock et al., 2007). "
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    • "Interaction of these two streams is done at few levels in mammalian brains [19, 20] whereas many neurobiological, physiological, and psychological evidences show that the information coupling occur in many places for instance in STS level [21] and in different ways, that is, recurrent feedback loops [14]. Mutual links have suggested recurrent processing loops that permit interaction of top-down and bottom-up processing [14, 15, 22]. However, current neuroscience and psychophysics research specifies more extensive form signals influences on motion processing than previously assumed [15]. "
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    Full-text · Article · Sep 2014
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    • "INSAR the ventral stream [Kveraga, Boshyan, & Bar, 2007; Laycock, Crewther, & Crewther, 2007]. Thus, the inconsistent findings regarding impairment in dorsal and ventral visual streams may better be understood , as Tsermentseli, O'Brien, and Spencer [2008] have argued, as an abnormality in the interaction between dorsal and ventral visual streams in ASD. "
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