The perceived speed of a grating pattern has often been reported to slow as the contrast of the pattern is reduced (though there are some contradictory reports). The mechanism of this perceived slowing has not yet been established nor have the conditions under which the effect occurs (or does not occur). We have therefore examined a range of stimuli that differ upon such aspects as one versus two dimensions, periodic versus nonperiodic, and whether the stimuli occur within a static window. We have also examined a range of stimulus speeds, different types of motion, and simultaneous versus successive presentations. We have found evidence for contrast-induced changes in perceived speed in all our stimuli, and thus suggest that none of the stimulus factors listed above is critical in producing the effect. Though the pattern of results is complex and shows substantial intersubject variation, we generally found that slowly moving patterns presented simultaneously produced the greatest decrease in perceived speed with decreasing contrast. On the other hand faster speeds and successive presentation produced more veridical matches or even an increase in perceived speed with decreasing contrast.
DienerH CWistE RDichgansJBrandtT, 1976“The spatial frequency effect on perceived velocity”Vision Research16169–176
8.
DistlerHBulthoffH H, 1996“Velocity perception in 3-D environments”Perception25Supplement, 58
9.
FerreraV PWilsonH R, 1991“Perceived speed of moving two-dimensional patterns”Vision Research31877–893
10.
FinneyD J, 1971Probit Analysis(Cambridge: Cambridge University Press)
11.
GegenfurtnerK RHawkenM J, 1996“Perceived velocity of luminance, chromatic and non-Fourier stimuli: Influence of contrast and temporal frequency”Vision Research361281–1290
12.
GeorgesonM AHarrisM G, 1978“Apparent foveofugal drift of counterphase gratings”Perception7527–536
13.
GogelW CMcNultyP, 1983“Perceived velocity as a function of reference mark density”Scandinavian Journal of Psychology24257–265
14.
GrazianoM S SAndersenR ASnowdenR J, 1994“The tuning of MST neurons to spiral stimuli”Journal of Neuroscience1454–67
15.
HarrisM G, 1986“The perception of moving stimuli: a model of spatiotemporal coding in human vision”Vision Research261281–1287
16.
HawkenM JGegenfurtnerK RTangC, 1994“Contrast dependence of colour and luminance motion mechanisms in human vision”Nature (London)367268–270
17.
KooiF KDe ValoisK KGrosofD HDe ValoisR L, 1992“Properties of recombination of one-dimensional motion signals into a pattern-motion signal”Perception & Psychophysics52415–424
18.
LedgewayTSmithA T, 1995“The perceived speed of second-order motion and its dependence on stimulus contrast”Vision Research351421–1434
19.
LivingstoneM SHubelD H, 1988“Segregation of form, color, movement and depth: anatomy, physiology and perception”Science240740–749
20.
McKeeS PSilvermanG HNakayamaK, 1986“Precise velocity discrimination despite random variations in temporal frequency and contrast”Vision Research26609–619
21.
McKeeS PWatamaniukS N J, 1994“The psychophysics of motion perception”, in Visual Detection of Motion Eds SmithA TSnowdenR J(London: Academic Press) pp 85–114
22.
NakayamaKTylerC W, 1981“Psychophysical isolation of movement sensitivity by the removal of familiar position cues”Vision Research21427–433
23.
PeterkenCBrownBBowmanK, 1991“Predicting the future position of a moving target”Perception207–16
24.
ReganDBeverleyK I, 1978“Looming detectors in the human visual pathway”Vision Research18415–421
25.
RosenbaumD A, 1975“Perception and extrapolation of velocity and acceleration”Journal of Experimental Psychology: Human Perception and Performance1395–403
26.
SmithA TEdgarG K, 1990“The influence of spatial frequency on perceived temporal frequency and speed”Vision Research301467–1474
27.
SmithA TEdgarG K, 1991“The separability of temporal frequency and velocity”Vision Research31321–326
28.
SmithD R RDerringtonA M, 1996“What is the denominator for contrast normalization?”Vision Research363759–3766
29.
SnowdenR J, 1994“Motion processing in the primate cerebral cortex”, in Visual Detection of Motion Eds SmithA TSnowdenR J(London: Academic Press) pp 51–83
30.
SnowdenR J, 1997“Perceived speed: effects of field size and background texture”Investigative Ophthalmology & Visual Science38(4) S1167
31.
SnowdenR JStimpsonNRuddleR A, 1998“Speed perception fogs up as visibility drops”Nature (London)392450
32.
SnowdenR JTreueSAndersenR A, 1992“The response of neurons in area V1 and MT of the alert rhesus monkey to moving random dot patterns”Experimental Brain Research88389–400
StoneL SThompsonP, 1992“Human speed perception is contrast dependent”Vision Research321535–1549
35.
StoneL SWatsonA BMulliganJ B, 1990“Effect of contrast on the perceived direction of a moving plaid”Vision Research301049–1067
36.
ThompsonP, 1976Velocity Aftereffects and the Perception of Movement PhD Thesis, University of Cambridge, Cambridge, UK
37.
ThompsonP, 1982“Perceived rate of movement depends on contrast”Vision Research22377–380
38.
ThompsonP, 1993“Motion psychophysics”, in Visual Motion and Its Role in the Stabilization of Gaze Eds MilesF AWallmanJ(Amsterdam: Elsevier) pp 29–52
39.
ThompsonPStoneL S, 1997“Contrast affects flicker and speed perception differently”Vision Research371255–1260
40.
ThompsonPStoneL SBrooksK, 1995“Speed perception in the fovea is not always independent of contrast”Perception24Supplement, 2
41.
ThompsonPStoneL SSwashS, 1996“Speed estimates from grating patches are not contrast-normalized”Vision Research36667–674
42.
TolhurstD JSharpeC RHartG, 1973“The analysis of the drift rate of moving sinusoidal gratings”Vision Research132545–2555
43.
TreueSSnowdenR JAndersenR A, 1993“The effect of transiency on perceived velocity of visual patterns: a case of ‘temporal capture’”Vision Research33791–798
