Fig. 5.

Low (a, c) and high (b, d) power photomicrographs of cresyl violet-stained coronal sections through an intermediate level of the frontal pole taken from a representative marmoset from both the orbital (a, b) and lateral (c, d) lesioned groups. The extensive cell loss in the orbital (ORB) prefrontal cortex ina is in stark contrast to the dense layering of neurons seen in the same region in c. Similarly, the almost total loss of neurons in the lateral prefrontal cortex (LAT) in c is in marked contrast to the dense layering of neurons seen in the same region ina. The stars mark the same locations in each pair of low and high power photomicrographs (e.g.,a and b, c andd); large arrowheads in band d mark the boundaries between the cortex and white matter; small arrowheads in a mark the lateral and medial boundaries of the orbital prefrontal lesion;small arrowheads in c mark the medial and dorsal boundaries of the lateral prefrontal lesion. Scale bars:a, c, 1 mm; b, d, 400 μm. M, Medial prefrontal cortex; PM, premotor cortex.