ORGANIZATION OF TEXTURE SEGREGATION PROCESSING IN PRIMATE VISUAL-CORTEX

We investigated the intracortical organization of neuronal mass activi ty that is related to texture segregation on the basis of orientation contrast. Evoked potentials were recorded to a stimulus, signalling a contribution from texture segregation-sensitive mechanisms by means of specific response components. The specific components could only be r ecorded when textons had a spatial organization that leads to the perc ept of image segmentation. Equivalent dipole estimations of the specif ic response components suggested the presence of texture segregation-r elated activity in the primary visual cortex. These results were corro borated by current-source-density analysis of intracortical recordings in the awake monkey. A specific involvement of layers 2/3 and 5 of ar ea 17 in the global process of image segmentation could be demonstrate d.