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PubMed · 12855249

Spatial frequency processing in inferred PC- and MC-pathways.

Anna Leonova·Joel Pokorny·Vivianne C Smith
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Abstract

The goal of this study was to investigate the role of inferred parvocellular (PC) and magnocellular (MC) pathways in spatial contrast sensitivity. Localized, spatially narrow-band patterns (sixth derivatives of Gaussians, D6s) were presented at various peak spatial frequencies. When the D6 appeared on a pulsed luminance pedestal (Pulsed-Pedestal Paradigm), the spatial contrast sensitivity showed a band-pass shape with good contrast sensitivity at medium spatial frequencies. When the D6 appeared on a steady luminance pedestal (Steady-Pedestal Paradigm), the spatial contrast sensitivity showed a low-pass shape with decreased sensitivity at high spatial frequencies. The band-pass CSF was interpreted as reflecting PC-pathway mediation; the lower spatial frequency region of the low-pass CSF as reflecting MC-pathway mediation.

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Contrast SensitivityGeniculate BodiesHumansPhotic StimulationRetinaSpace PerceptionVisual PathwaysJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Anna Leonova, Joel Pokorny, Vivianne C Smith. 2003. Spatial frequency processing in inferred PC- and MC-pathways.. https://doi.org/10.1016/s0042-6989(03)00333-x

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