University of Tübingen
Title: Formulating and understanding vision: progress in theory and experiments
Abstract: Using our own brains to study our brains is extraordinary. In vision — the dominant primate sense — this makes us blind to our own blindness, leading us astray in asking theoretical questions. Centuries of work, including contributions from Kepler through Newton to Maxwell, laid foundation for understanding retina, mainly as an optical sampling device of the environment. Then, within just a decade (1950s – 60s), electrophysiological recordings leapt from retinal neurons to those in primary visual cortex (V1), revealing how optical signals are transformed to signals in individual neurons. Yet progress beyond V1 has been markedly slower than the leap from retina to V1.
What, then, is vision as it advances from retina to mind? A suitable formulation must recognize the brain’s information processing (attentional) bottleneck, which admits a tiny fraction of retinal visual input for deeper processing. A fresh formulation (Zhaoping 2014, 2019) posits vision as looking and seeing: looking — mainly by shifting gaze — selects information for entry into the bottleneck, while seeing recognizes or infers object properties from what is selected. Since we are blind to non-selected inputs, understanding looking — which often occurs before and even without seeing — is essential to understanding vision as a whole.
This formulation generates falsifiable predictions, tested experimentally in psychology and neuroscience. Discoveries include a functional role of V1 in exogenously guiding gaze shifts, the involvement of neural circuits within and beyond V1, and new visual illusions in the process of seeing (Zhaoping 2025). These advances yield uncanny insights into our vision and mind. This framework can be extended to understand senses and minds of other animal species, e.g., rodents, fish, birds, bats, insects, many dominantly use a non-visual sense to “see” their world (Zhaoping 2023).
References:
Zhaoping, L. (2014) Understanding vision: theory, models, and data, Oxford University Press.
Zhaoping, L. (2019) A new framework for understanding vision from the perspective of the primary visual cortex. Current Opinion in Neurobiology, volume 58, page 1-10.
Zhaoping, L. (2023) Peripheral and central sensation: Multisensory orienting and recognition across species, Trends for Cognitive Sciences, Vol 27, issue 6, page 539-552.
Zhaoping, L. (2025) Testing the top-down feedback in the central visual field using the reversed depth illusion, iScience, Volume 28, Issue 4, 112223.