# Categorical Perception Goldstone and Hendrickson **Opening (not a real abstract):** Categorical perception Robert L. Goldstone∗ and Andrew T. Hendrickson Categorical perception (CP) is the phenomenon by which the categories possessed by an observer influences the observers’ perception. Experimentally, CP is revealed when an observer’s ability to make perceptual discriminations between things is better when those things belong to different categories rather than the same category, controlling for the physical difference between the things. We consider several core questions related to CP: Is it caused by innate and/or learned categories, how early in the information processing stream do categories influence perception, and what is the relation between ongoing linguistic processing and CP? CP for both speech and visual entities are surveyed, as are computational and mathematical models of CP. CP is an important phenomenon in cognitive **Authors:** [[Robert L. Goldstone]]