Figure 10.

Strong ipsilateral representation after neonatal pyramidotomy. ICMS was performed on four control rats and four rats with neonatal pyramidotomy. Twenty-three sites were mapped in the right cortex, which was in the uninjured hemisphere of rats with neonatal pyramidotomy. Responses from both forelimbs (contralateral and ipsilateral) were recorded. The sizes of the circles were inversely proportional to the threshold for provoking a movement, as indicated in the scale at right. Responses in individual rats were shaded a light color, and the darkness of the circles indicated how many rats of the four rats had responses at each site. In control rats (A), the responses were mainly on the contralateral forelimb. However, in the rats with neonatal pyramidotomy (B), stronger responses were noted in the ipsilateral forelimb in comparison to that of the control rats. In contrast, the responses from the contralateral forelimb of the rats with neonatal pyramidotomy were less robust than that of the control rats.