Abstract
Functional magnetic resonance imaging (fMRI) studies have relied on multivariate analysis methods to decode visual motion direction from measurements of cortical activity. Above-chance decoding has been commonly used to infer the motion-selective response properties of the underlying neural populations. Moreover, patterns of reliable response biases across voxels that underlie decoding have been interpreted to reflectmapsof functional architecture. Using fMRI,weidentified a direction-selective response bias inhumanvisual cortex that: (1) predicted motion-decoding accuracy; (2) depended on the shape of the stimulus aperture rather than the absolute direction of motion, such that response amplitudes gradually decreased with distance from the stimulus aperture edge corresponding to motion origin; and 3) was present in V1, V2, V3, but not evident inMT+, explaining the higher motion-decoding accuracies reported previously in early visual cortex. These results demonstrate that fMRI-based motion decoding has little or no dependence on the underlying functional organization of motion selectivity.
Original language | English (US) |
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Pages (from-to) | 12601-12615 |
Number of pages | 15 |
Journal | Journal of Neuroscience |
Volume | 34 |
Issue number | 37 |
DOIs | |
State | Published - Sep 10 2014 |
Keywords
- Coarse-scale bias
- Direction preference
- FMRI
- Motion decoding
- Multivariate classification
- Visual cortex
ASJC Scopus subject areas
- General Neuroscience