Abstract
Introduction: Categorical color perception has been considered to be common to human being by nature regardless of language. However, it is difficult to show clear psychophysical evidence for it, because separating categorical color perception from language in normal subjects is very difficult. Purpose: To investigate the characteristics of categorical color perception through a patient with color aphasia and the dissociation between form and color. Method: The patient was 32-year-old, right handed woman, who was suffered from subarachnoidal hemorrhage and subsequent cerebral herniation. Broca's aphasia, color aphasia and impairment of color pointing for line drawing (such as banana or apple) were observed. The performance of color card pointing after listening to color name was 6/12. Color naming was impossible because of Broca's aphasia. Ophthalmologic examinations showed right homonymous hemianopsia and normal visual acuity. Color vision test by Ishihara pseudo-isochromatic plates and panel D-15 test showed normal performance. We also tested her categorical color perception by asking her to group the colors of a category in a color chart used in the study of Berlin and Kay (1969). Result and Discussion: Although there was tendency that green and blue was classified as same group, she could categorize the colors in the chart almost the same as normal subjects.In this case, it is difficult to conclude definitely because color language was not completely impaired. However, the present result may support that categorical color perception is independent of language.