The role of color in object recognition: Evidence from visual agnosia

Abstract

The extent to which the presence of color in a visual display (perceptual or surface color) assists object recognition has been much debated. Whereas edge-based theories argue that perceptual color is not helpful, surface-based theories claim that color is a valuable and salient clue. Consistent with the edge-based account, we showed that surface color plays a minimal role in aiding object recognition in a brain-damaged patient with an object recognition deficit (visual agnosia) but normal color processing. We found, however, that under certain conditions, such as when shape is ambiguous, stored knowledge of color can help disambiguate the object. Based on these results, we argue that the contribution of perceptual color is small but that long-term color knowledge plays an important top-down role in object recognition.

Key words:

• agnosia
• color
• object recognition
• surface cues