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: 10.28). 02/2007; 31(3):363-76. DOI: 10.1016/j.neubiorev.2006.10.003
Source: PubMed

ABSTRACT 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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    ABSTRACT: Research on psychophysics, neurophysiology, and functional imaging shows particular representation of biological movements which contains two pathways. The visual perception of biological movements formed through the visual system called dorsal and ventral processing streams. Ventral processing stream is associated with the form information extraction; on the other hand, dorsal processing stream provides motion information. Active basic model (ABM) as hierarchical representation of the human object had revealed novelty in form pathway due to applying Gabor based supervised object recognition method. It creates more biological plausibility along with similarity with original model. Fuzzy inference system is used for motion pattern information in motion pathway creating more robustness in recognition process. Besides, interaction of these paths is intriguing and many studies in various fields considered it. Here, the interaction of the pathways to get more appropriated results has been investigated. Extreme learning machine (ELM) has been implied for classification unit of this model, due to having the main properties of artificial neural networks, but crosses from the difficulty of training time substantially diminished in it. Here, there will be a comparison between two different configurations, interactions using synergetic neural network and ELM, in terms of accuracy and compatibility.
    09/2014; 2014:723213. DOI:10.1155/2014/723213
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    ABSTRACT: Declaration Declaration This work has not previously been accepted in substance for any degree and is not concurrently submitted in candidature for any degree.
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    Neuropsychologia 01/2015; 69. DOI:10.1016/j.neuropsychologia.2015.01.046 · 3.45 Impact Factor


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Jan 3, 2015