Contrast dependency and prior expectations in human speed perception.

ABSTRACT: The perceived speed of moving objects has long been known to depend on image contrast. Lowering the contrast of first-order motion stimuli typically decreases perceived speed - the well-known "Thompson effect". It has been suggested that contrast-dependent biases are the result of optimal inference by the visual system, whereby unreliable sensory information is combined with prior beliefs. The Thompson effect is thought to result from the prior belief that objects move slowly (in Bayesian terminology, a "slow speed prior"). However, there is some evidence that the Thompson effect is attenuated or even reversed at higher speeds. Does the effect of contrast on perceived speed depend on absolute speed and what does this imply for Bayesian models with a slow speed prior? We asked subjects to c

SUBMITTER: Sotiropoulos G 

PROVIDER: S-EPMC4915944 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature