Fig. 11.

Location and extent of the cortical lesions in the 4 animals in the “restricted cortical lesion” group. A: histological reconstructions of the cerebral cortex are shown schematically for each case. Note that the lesions were focused on the primary auditory cortex, which makes up only part of the MEG. In 2 animals, largely symmetrical lesions were made on each side; in the other 2, a greater proportion of the right cortex was aspirated, although the caudal part of the MEG, where A1 is located, was damaged on the left side also. In case F0509, the lesion also included part of the left suprasylvian gyrus. Coronal section in B shows for case F0317 that nearly all the cortical layers had been removed in the central part of the lesions and that there was virtually no encroachment on the underlying white matter. C: atrophy at the level of the A1 in the left hemisphere in cases F0318 and F0509. Compared with the control case shown in the left panel (F0640), the cortex is clearly damaged, with atrophy of the supragranular layers in F0318 (middle panel) and of all the layers in F0509 (right panel). Calibration bars are 2 mm in A and B and 0.5 mm in C. ps, pial surface; wm, white matter.