Poster F100, Tuesday, March 27, 8:00-10:00 am, Exhibit Hall C
Color categorization without color naming: neuropsychological evidence
Katarzyna Siuda-Krzywicka1, Christoph Witzel2, Emma Chabani1, Myriam Taga3, Laurent Cohen1,4, Paolo Bartolomeo1; 11. Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital de la Pitié-Salpêtrière, Paris, France, 2Justus-Liebig-Universität Gießen, 3University of East London, 4Hôpital de la Pitié Salpêtrière Paris, France
Colors vary continuously, however we group them into distinct categories associated with specific color names (green, blue, etc.). It is an open question whether color categories are a product of linguistic labeling and thus, if categorizing colors requires transferring color information between visual and language areas. To answer this question, we investigated color categorization in a brain-damaged patient with a rare, selective impairment of color naming. The patient’s lesion affected the left mesial occipitotemporal areas and the splenium of corpus callosum, abolishing direct communication between the bilateral visual cortex and language areas in the left hemisphere. We designed a new task measuring color categorization without explicit color naming. On each trial, we presented two color pairs, one from the same category (e.g. light-green, dark-green), the other from different categories (e.g. orange and yellow). The patient and a group of healthy controls (n=50) had to indicate pairs containing same-category colors. In a control experiment, the patient and healthy controls (n=12) named the colors from the color-categorization task. The patient performed normally on color categorization. Yet, his color naming was severely impaired only in chromatic, but not achromatic colors (black, white, grey). This chromaticity-effect was considerably weaker in color-categorization. Our results challenge the hypothesis that color categorization, like naming, involves language system. Our findings also indicate that compared with color categorization, color naming strongly segregates chromatic and achromatic information. Given that color names refer to color categories, our findings suggest that the processes of non-linguistic categorization are fundamental for color naming.
Topic Area: PERCEPTION & ACTION: Vision