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Psychology

How Visual Illusions Reveal the Brain's Processing Shortcuts

Quick fact

In the famous Müller-Lyer illusion, the line with inward-pointing arrows looks shorter than the one with outward-pointing arrows, even though they are exactly the same length. This happens because the brain interprets the arrows as depth cues from corners or edges.

Why this is interesting

Have you ever looked at an illusion where two identical lines appear different lengths? Your eyes send the same image, yet your brain insists otherwise—proving that seeing is not believing, but interpreting.