A and B	:	Coronal sections through the orbitofrontal cortex of a monkey (medial is to the right; dorsal at the top). At the border of layers 1 and 2, apical dendrites of layer 2 neurons form distinct clusters (visualized by immunohistochemistry for microtubule associated protein (MAP2)).
B	:	Adjacent section reacted by zinc histochemistry. Note the patches of zinc positive terminations, similar in size and location to the dendritic patches. Scale bar = 1.0mm for A and B.
C	:	EGFP expression in pyramidal neurons in layers 5 and 6 of rat cortex, after an injection in thalamus. Boxed images at right are higher magnification to show distribution and shape of dendritic spines.