Attentional effects on afterimages: theory and data.

We explore attentional effects on afterimages in the framework of the FACADE model of visual perception. We first show that the FACADE model can account for the experimental findings of Suzuki and Grabowecky [Suzuki, S., & Grabowecky, M. (2003). Attention during adaptation weakens negative afterimages. Journal of Experimental Psychology: Human Perception and Performance 29, 793-807] that afterimages are weaker when the inducing stimulus is attended. We then analyze the model's behavior with attentional influences on a two-stimulus afterimage studied by Francis and Rothmayer [Francis, G., & Rothmayer, M. (2003). Interactions of afterimages for orientation and color: Experimental data and model simulations. Perception & Psychophysics 65, 508-522]. The model predicts that attentional focus directed towards the first stimulus has little effect on afterimage strength. In contrast, the model predicts that attentional focus on the second stimulus should increase the strength of the afterimage compared to when attention is focused elsewhere. Moreover, the model predicts that the attentional effects on the second stimulus should vary with time after offset of the second inducing stimulus. All of the model predictions are validated in an experiment. The model and experimental results extend and clarify previous explanations of attentional effects and afterimages.