A functional and perceptual signature of the second visual area in primates

1] Center for Neural Science, New York University, New York, New York, USA [2] [3].
Nature Neuroscience (Impact Factor: 14.98). 05/2013; 16(7). DOI: 10.1038/nn.3402
Source: PubMed

ABSTRACT There is no generally accepted account of the function of the second visual cortical area
(V2), partly because no simple response properties robustly distinguish V2 neurons from those in
primary visual cortex (V1). We constructed synthetic stimuli replicating the higher-order
statistical dependencies found in natural texture images, and used them to stimulate macaque V1 and
V2 neurons. Most V2 cells responded more vigorously to these textures than to control stimuli
lacking naturalistic structure; V1 cells did not. fMRI measurements in humans revealed differences
between V1 and V2 that paralleled the neuronal measurements. The ability of human observers to
detect naturalistic structure in different types of texture was well predicted by the strength of
neuronal and fMRI responses in V2 but not in V1. Together, these results reveal a novel and
particular role for V2 in the representation of natural image structure.

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Available from: Eero P. Simoncelli, Feb 11, 2014
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