High-Level Feedback in Vision: Rules of Prediction, Suppression, and Filling-In

High-Level Feedback in Vision: Rules of Prediction, Suppression, and Filling-In 

Description of the general focus of the symposium: 

Perception is increasingly viewed as an inferential process in which the brain actively predicts its sensory inputs and updates its beliefs based on prediction errors. Yet, even within this predictive processing framework, key questions remain unresolved: What kind of information is fed back into the visual system? At what level of abstraction are predictions formulated? And how do these signals shape representations when sensory evidence is weak, ambiguous, or entirely absent?  

This symposium focuses on high-level feedback in vision, with an emphasis on the rules and the content of predictive signals. On the one hand, we ask how predictive feedback operates in a normally sighted visual system: whether prediction errors in early areas are dominated by high-level, abstract expectations rather than low-level features, and under what conditions expectations selectively sharpen relevant information or suppress competing inputs in cluttered scenes. These questions speak directly to the computational role of feedback in the visual hierarchy and to ongoing debates about sharpening versus dampening accounts of expectation.  

On the other hand, we examine the content of predictions when input is missing – either transiently, as in occluded scenes, or chronically, as in congenital blindness. Here, the key issue is whether the brain fills in only coarse contextual information or whether it actively represents unseen objects and semantic properties with finegrained, feature-specific codes. Studying blindness also reveals how high-level, topdown signals can repurpose “visual” cortex for abstract, non-visual computations, providing a strong test of functional plasticity within a predictive brain. 

By bringing together work on prediction errors, selective suppression, occlusion, and blindness, the symposium aims to converge on a feature-specific, task-sensitive view of predictive processing in vision -- one that clarifies what the brain sends back, when it does so, and how this feedback sculpts both moment-to-moment perception and long-term cortical organization. 

Speaker 1: David Richter  

AffMind, Brain and Behavior Research Center (CIMCYC), University of Granada, Granada, Spain Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, the Netherlands  

What Does the Brain Predict? A Case for High-Level Prediction in the Visual System. 

Speaker 2: Jakub Szewczyk  

Institute of Psychology, Jagiellonian University, Kraków, Poland  

When Expectations Silence the Background: Selective Sharpening in Object Vision 

Speaker 3: Mandy Bartsch  

Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, the Netherlands  

Filling in the Blanks: representation of occluded scene parts in early visual cortex 

Speaker 4: Łukasz Bola  

Institute of Psychology, Jagiellonian University, Kraków, Poland Center for Brain Research, Jagiellonian University, Kraków, Poland.  

Semantic representations in the visual cortex of blind and sighted humans