Prediction of saccadic consequences and visual targets' perception

26 April 2016
Begin time: 
End time: 
CITEC building, room: 2.015

Each time we move our eyes the images of the visual targets shift on our retina. However, the world is not perceived as constantly jumping with each saccade - it appears stable and continuous. Several hypotheses were proposed to account for this phenomenon of visual stability. I will provide evidence for one of them, namely spatiotopic trans-saccadic fusion – i.e. the integration of two different pre- and post-saccadic images into a single, visible percept. Our findings suggest that predictive mechanisms might influence the perception of post-saccadic visual targets.
The second part of my talk deals with the perception of pre-saccadic targets. We can recognize visual objects presented in the periphery even if their cortical representation differs radically across saccades. Recently Herwig et al. (2015) found that the perception of shape demonstrates a saccade-contingent learning effect. In a follow-up study, we replicated these results and found that they were similar when participants had to maintain their fixation. This suggests that a general associative learning process, independent of saccade execution, contributes to the peripheral perception of shape – and our impression of object uniformity across saccades.