Decision level adaptation inmotion perception

Abstract

Prolonged exposure to visual stimuli causes a bias in observers’ responses to subsequent stimuli. Such adaptation-induced biases are usually explained in terms of changes in the relative activity of sensory neurons in the visual system which respond selectively to the properties of visual stimuli. However, the bias could also be due to a shift in the observer’s criterion for selecting one response rather than the alternative, adaptation at the decision level of processing rather than the sensory level. We investigated whether adaptation to implied motion is best attributed to sensory-level or decision-level bias.