Where is the object? Two answers. Retinal position: computed from photon impact coordinates, geometrically correct. Perceived position: where the object appears to be, shifted by context, illusions, and perceptual biases. These differ measurably — visual illusions demonstrate that perceived position can deviate degrees from retinal reality.
Macaque inferior temporal cortex (arXiv:2603.11248) encodes perceived position, not retinal position. When presented with stimuli that induce positional illusions, IT neurons track where the object appears to be, not where it is. The representation is faithful to subjective experience, not to physical reality.
Every current artificial vision network fails to do this. CNNs, vision transformers, CLIP, DINOv2 — all encode positions in coordinates that do not track perceptual illusions. They are more “accurate” than biology in the geometric sense and less accurate in the perceptual sense. Biologically-inspired coordinate transforms partially rescue artificial systems, but the native representations lack the warping.
The implication is that high-level visual processing in IT cortex is not computing objective features and then subjecting them to illusory distortion. The illusion is not a bug that contaminates an accurate signal. The perceived coordinates are the computation. The brain's position code serves behavior, not measurement — and behavior operates in perceived space, not physical space. An organism reaches for where the object appears, not where it is.
Artificial systems optimized for geometric accuracy are solving a different problem than the one biology solves. The gap is not a failure of artificial systems to match biology. It is a difference in what the systems are for.