Abstract
Texture segregation, an example of scene segmentation, can be divided into two different processes: texture boundary detection and subsequent surface segregation (Lamme et al., 1999). Neural correlates of texture boundary detection have been found in monkey V1 (Rossi et al., 2001); whether surface segregation can be measured in monkey V1 (Lamme, 1995, Rossi et al., 2001), or whether texture boundary detection and surface segregation can also be measured in human V1 is more controversial (Kastner et al). Here we present EEG and fMRI data that has been measured during three different conditions in human subjects. Within these conditions, we varied surface segregation independent of textures boundaries. In this way, we were able to show that a) neural correlates of texture boundary detection are present in human V1, b) neural correlates of surface segregation are present in human V1, c) texture boundary detection, as measured with EEG, starts at approximately 60 msec, and d) surface segregation starts at approximately 100 msec.
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