Current theories of second-order motion perception postulate that such motion is detected
by either a high-level mechanism which computes the temporal correspondences between …

In this experiment, the term" second-order motion"(SOM) refers to non-Fourier motion of 2nd-
order contours. Although SOM can support motion perception, it is not clear what visual …

Lu Sperling [Vision Res. 35, 2697 (1995)] proposed that human visual motion perception is
served by three separate motion systems: a first-order system that responds to moving …

Motion in the retinal image may occur either in the form of spatiotemporal variations in
luminance (first-order motion) or as spatiotemporal variations in characteristics derived from …

We measured the ability of human observers to discriminate the direction of motion of
different spatial patterns presented for durations ranging from 0.021 to 0.67 sec. The …

Evidence bearing on the question of whether first-order and second-order motion are
detected by use of the same or different principles has been sought. This question was …

We have investigated first-order artifacts in second-order motion perception. Subjects were
required to identify the orientation and direction of a drifting sinusoidal contrast modulation …

There is considerable evidence that second-order motion, such as motion consisting of a
drifting contrast modulation, is detected separately from first-order motion. Some previous …

The experiments reported here address the issue of whether the pathways which extract
motion from first-order and second-order spatial patterns remain separate or whether they …

When a moving aperture contains a drifting grating, the perception of aperture movement is
strongly affected by the grating movement. We have studied this interaction, using a moving …