Second-order Motion Perception
Second-order motion is motion in which the moving contour is defined by contrast, texture, flicker or some other quality that does not result in an increase in luminance or motion energy in the Fourier spectrum of the stimulus. There is much evidence to suggest that early processing of first- and second-order motion is carried out by separate pathways. Second-order mechanisms have poorer temporal resolution and are low-pass in terms of the range of spatial frequencies to which they respond. Second-order motion produces a weaker motion aftereffect unless tested with dynamically flickering stimuli. First and second-order signals appear to be fully combined at the level of Area V5/MT of the visual system.
Read more about this topic: Motion Perception
Famous quotes containing the words motion and/or perception:
“As I walked on the glacis I heard the sound of a bagpipe from the soldiers’ dwellings in the rock, and was further soothed and affected by the sight of a soldier’s cat walking up a cleated plank in a high loophole designed for mus-catry, as serene as Wisdom herself, and with a gracefully waving motion of her tail, as if her ways were ways of pleasantness and all her paths were peace.”
—Henry David Thoreau (1817–1862)
“The shift from the perception of the child as innocent to the perception of the child as competent has greatly increased the demands on contemporary children for maturity, for participating in competitive sports, for early academic achievement, and for protecting themselves against adults who might do them harm. While children might be able to cope with any one of those demands taken singly, taken together they often exceed children’s adaptive capacity.”
—David Elkind (20th century)