Measuring temporal contrast sensitivity across the visual field and visual cortex using fMRI

摘要

The visual system's sensitivity to both contrast and temporal frequency changes across visual space. In general, the fovea is dominated by cells contributing to the parvocellular (PC) pathway and the ratio of parvo to magnocellular (MC) retinal ganglion cells decreases with increasing eccentricity a?? leading to higher temporal sensitivity and, potentially, less linear responses to contrast in the periphery. Here, we describe a series of fMRI experiments that examine the relationship between eccentricity, contrast sensitivity, temporal frequency tuning and pRF size in five human visual areas with well-defined eccentricity maps (V1, V2, V3, V4, V3a).