The Cytoarchitecture and Cellular Organisation of the Cerebral Cortex

The development in the early part of the present century of new methods for fixation and staining of the brain opened up new possibilities for detailed examination of the cytoarchitecture of the cerebral cortex. Through the work of Ramón y Cajal and others, it soon became apparent that the cerebral cortex could be subdivided into areas of specific structure. The first cortical map based on cytoarchi- tectural differences was published in 1905 by Campbell, who divided the cortex into 20 areas. A few years later (1909) Brodmann published a map that has been widely reproduced which divided the cortex into about 50 separate zones (Fig. 11.1). Other maps have since been suggested, but Brodmann’s labelling is still the one most extensively employed and it will therefore be used in the following (Fig. 11.2).