Cytochrome-oxidase blobs in cat primary visual cortex.
Cytochrome-oxidase blobs are central to two of the most influential ideas in contemporary visual neuroscience--cortical modularity and parallel processing pathways. In particular, the regular 2D array of cytochrome-oxidase-rich blobs in primate visual cortex is arguably the most compelling evidence for cortical modularity and has been hypothesized to mark a separate processing stream through the visual cortex. Although previously a variety of mammals have been studied, blobs have only been demonstrated in the visual cortex of primates, which has led to the conclusion that blobs represent a primate-specific feature of visual cortical organization. Here we demonstrate the presence of cytochrome-oxidase blobs in a nonprimate species. Throughout the full tangential extent of layers II-III in cat visual cortex the cytochrome-oxidase staining pattern is distinctly patchy, with the darkly stained blobs forming a regular 2D array. In addition, the blobs in cat visual cortex are functionally related to the underlying ocular dominance columns. The presence of cytochrome-oxidase blobs in the cat clearly demonstrates that they no longer can be considered a primate-specific feature of visual cortical organization.
Murphy
K M
KM
McMaster University, Department of Psychology, Hamilton, Ontario, Canada.
Jones
D G
DG
Van Sluyters
R C
RC
D000818:Animals; D002415:Cats; D003624:Darkness; D004292:Dominance, Cerebral; D003576:Electron Transport Complex IV / Q000032:analysis*; D008027:Light; D008322:Mammals; D011323:Primates; D013045:Species Specificity; D014793:Visual Cortex / Q000033:anatomy & histology / Q000201:enzymology* / Q000502:physiology*; D014796:Visual Perception
D003576:Electron Transport Complex IV