Colour anomia restricted to the left visual hemifield after splenial disconnexion.

In a patient with damage to the right occipital lobe and to the splenium of the corpus callosum, an incomplete colour anopia in the left upper quadrants and a colour anomia was found for the complete left visual hemifield beyond 2 degrees eccentricity. The patient had no difficulty in recognising coloured targets when presented in the periphery of the left visual hemifield and in the foveal region, but could not name them correctly. The results suggest that the lesion of the splenium of the corpus callosum disconnects the right visual cortex from the language areas of the left hemisphere, and the specific disturbance of colour naming is the consequence.