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Geometric

Ebbinghaus / Titchener Circles

Size Contrast & Spatial Context Distortion • Two identical central circles appear remarkably different sizes.

Parameter Controls

Adjust procedural mathematical parameters in real-time to alter or break the illusion.

Left Outer Orbs Size 1.8
Right Outer Orbs Size 0.5

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🧠 Scientific Explanation & Psychophysics

Underlying Mechanism: Ventral Stream Contextual Size Contrast

Visual size perception in the ventral ('what') pathway relies heavily on contextual surround comparison. Neurons in V1 with large receptive fields integrate surrounding geometry, altering the perceived scale of the enclosed shape.

Why This Works in the Brain

The visual cortex processes incoming sensory information using specialized receptive fields and cortical feature detectors. Illusions occur when mathematical geometries produce conflicting spatial signals, exposing how the brain constructs subjective perception from objective electromagnetic light waves.

💬 Community Notes & Observations

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