XXXX in monkeys.

@entity1 @entity1018 @entity227 @entity16 @entity1650 @entity3641 @entity1779
In @entity1 @entity1779 , extrastriate @entity16 produces a @entity1018 , with relative sparing of non-chromatic vision. The critical lesion appears to be in a medial occipito-temporal area, occupying the lingual and caudal fusiform gyri; positron emission tomography has shown that this cortical region is one of several activated in normal @entity1 observers during colour vision tasks. Attempts to find an analogous 'colour centre' in the cortex of monkeys have not been successful. In particular, ablation of cortical area V4, sometimes thought on physiological grounds to be more involved in wavelength and colour coding than any other visual cortical area, produces only mild @entity1650 . In the present study we tested the colour vision of monkeys after cortical ablations that mainly or entirely spared area V4. One group of monkeys (group AT) received ablations in the temporal lobe anterior to area V4, and a second group (group MOT) received ablations in a medial occipito-temporal area roughly corresponding in cranial location to the lesion that produces @entity1 @entity1779 . The animals in group MOT showed no @entity227 . Group AT, in contrast, had a severe @entity227 , with a relative sparing of non-chromatic vision. Their behaviour was indistinguishable from that of a @entity1 @entity1 with total cerebral @entity3641 who had been tested on the same tasks. These results show that area V4 in macaque monkeys is not analogous, and probably not homologous, to the @entity1 colour centre. Instead, they suggest that the area of the monkey's brain corresponding to the colour area in the @entity1 brain is in the temporal cortex, anterior to area V4.
