Mechanisms of visual motion detection
Paul R Schrater ,
David C Knill ,
and
Eero P Simoncelli
Published in:
Nature:Neuroscience
Vol 3, num 1, pp 64-68
January, 2000.
© Macmillan Magazines Ltd.
Visual motion is processed by neurons in primary visual cortex that are
sensitive to the spatial orientation and speed of the visual input. Many
models of local velocity computation are based on a second stage that pools the
outputs of first-stage neurons selective for different orientations, but the
nature of this pooling remains controversial. In a psychophysical detection
experiment, we find that human subjects show near-perfect summation of image
energy when it is distributed uniformly across all orientations, but poor
summation when it is concentrated in specific orientation bands. The
data are consistent with a model that integrates uniformly over all
orientations, even when this strategy is sub-optimal.
Reprint (165k, pdf)
/
Manuscript (236k, gzip'ed PostScript)
/
Accompanying News & Views article (490k, pdf)
/
EPS Web-Available Publications