ECVP 2019 - Hysteresis and adaptation in perceptual categorization, discrimination, and similarity judgment tasks


How we perceive a visual stimulus or the difference between two sequentially presented stimuli does not only depend on aspects of the presented stimuli, but also on the temporal context in which they are presented. In data from a perceptual categorization, a perceptual discrimination, and a similarity judgment task with both recognizable and non-recognizable morph series, we analyzed the effects of signal strength and response in the previous trial on the response in the current trial. Attractive effects of the previous response (i.e., hysteresis) were found in all three tasks. Under certain conditions, indications of repulsive effects of signal strength in the previous trial (i.e., adaptation) were also present. In addition, these context effects were stronger in tasks involving the non-recognizable morph series, suggesting that stronger categorization led to reduced attractive and repulsive context effects. The results are in accordance with Bayesian accounts of perception, where current sensory information is combined with prior information. We will also discuss planned research regarding individual differences in hysteresis and adaptation effects with other stimuli and tasks.

Aug 26, 2019
Leuven, Belgium