Dataset Information

Local opposite orientation preferences in V1: fMRI sensitivity to fine-grained pattern information.

ABSTRACT: The orientation of a visual grating can be decoded from human primary visual cortex (V1) using functional magnetic resonance imaging (fMRI) at conventional resolutions (2-3 mm voxel width, 3T scanner). It is unclear to what extent this information originates from different spatial scales of neuronal selectivity, ranging from orientation columns to global areal maps. According to the global-areal-map account, fMRI orientation decoding relies exclusively on fMRI voxels in V1 exhibiting a radial or vertical preference. Here we show, by contrast, that 2-mm isotropic voxels in a small patch of V1 within a quarterfield representation exhibit reliable opposite selectivities. Sets of voxels with opposite selectivities are locally intermingled and each set can support orientation decoding. This indicates that global areal maps cannot fully account for orientation information in fMRI and demonstrates that fMRI also reflects fine-grained patterns of neuronal selectivity.

SUBMITTER: Alink A

PROVIDER: S-EPMC5540976 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Local opposite orientation preferences in V1: fMRI sensitivity to fine-grained pattern information.

Alink Arjen A Walther Alexander A Krugliak Alexandra A Kriegeskorte Nikolaus N

Scientific reports 20170802 1

The orientation of a visual grating can be decoded from human primary visual cortex (V1) using functional magnetic resonance imaging (fMRI) at conventional resolutions (2-3 mm voxel width, 3T scanner). It is unclear to what extent this information originates from different spatial scales of neuronal selectivity, ranging from orientation columns to global areal maps. According to the global-areal-map account, fMRI orientation decoding relies exclusively on fMRI voxels in V1 exhibiting a radial or ...[more]

PMID: 28769042

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Dataset Information

Local opposite orientation preferences in V1: fMRI sensitivity to fine-grained pattern information.

Publications

Local opposite orientation preferences in V1: fMRI sensitivity to fine-grained pattern information.

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