Magnocellular pathway

Magnocellular Pathway Parvocellular-Blob Pathway Parvocellular-Interblob Pathway... 

Schizophrenia patients showed reduced amplitude and coherence of second harmonic responses in both conditions, but intact first harmonic responses in the windmill-dartboard condition (Q Figure 3.2-5). This indicates a significant loss in the magnocellular pathway, which contributes to the generation of the second harmonic component under these conditions. 

Patients with schizophrenia showed significantly reduced second harmonic responses but intact first harmonic responses. This finding of a differential deficit may indicate a significant loss in the magnocellular pathway. Bi, binocular eye condition Dom, dominant eye condition ND, nondominant eye condition, a, P < 0.01 b, P < 0.05. Reprinted with permission from Kim et al. (2005)... 

Keri S, Kiss I, Kelemen O, Benedek G, Janka Z. 2005b. Anomalous visual experiences, negative symptoms, perceptual organization and the magnocellular pathway in schizophrenia A shared construct Psychol Med 35 1445-1455. 

Martinez A, Hillyard SA, Dias EC, et al. 2008. Magnocellular pathway impairment in schizophrenia Evidence from fMRI. J Neurosci 28(30) 7492-7500. 

Figure 2.18 Organization of the visual system. Two main pathways, the magnocellular and the parvocellular pathways, can be distinguished. (Reproduced by permission from Massachusetts Institute of Technology. D. C. Van Essen and E. A Deyoe. Concurrent Processing in the Primate Visual Cortex. M. S. Grazzanida (ed.), The Cognitive Neurosciences, The MIT Press, pp. 383-400, 1995.)...

Thus, there appear to be alterations in both gray and white matter in low-level visual areas in schizophrenia and in two studies that examined the relationships with visual pathway function, anatomical deficits were related to magnocellular dysfunction (Butler et al., 2005 Martinez et al., 2008). 

Functional magnetic resonance imaging examination of the magnocellular visual pathway in nonpsychotic relatives ofpersons with schizophrenia. Schizophr Res 71 509-510. 

Keri S, Kelemen O, Janka Z, Benedek G. 2005a. Visual-perceptual dysfunctions are possible endophenotypes of schizophrenia Evidence from the psychophysical investigation of magnocellular and parvocellular pathways. Neuropsychology 19 649-656. 

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