Retinex processing from the fMRI study on V4 -Artistic Research of coloured Picture Using Functional MRI

摘要

Artists can imagine 2 kinds of coloured scenes with no recognizable objects. One is the abstract picture such as colour Mondrian, which includes geometric pattern: rectangles, circles and crosses. Another is the decorative texture such as Japanese traditional cloud pattern which is colour camouflage pattern and does not include geometric pattern. We created these 2 kinds of colour dot pattern stimuli composed of 4 iso-luminance colours and the same area and an achromatic version. These functional magnetic resonance imaging stimuli reveal multiple colour-sensitive areas in human ventral occipitotemporal cortex. The results showed that area V4 is highly activated by the stimulus of the abstract picture such as rectangle pattern and spiral but little activated by the stimulus of the decorative texture such as random colour dot picture and cloud pattern. We suggest V4 is activated by figures composed of colour dots with eye-like shape such as disks, crosses, gratings, spirals, and windmill-like figures, and V4 has low response to the camouflage figure in which colour dots do not include eye-like shapes.