Fig. 1. Focal epidural application of picrotoxin onto the MI through a chronically implanted, well induced c-Fos expression and increased metabolic activity in the underlying cortex and in the dorsolateral caudoputamen. A, An example of the microstimulation maps of MI on which stereotaxic coordinates for the implanted wells were based. The area in gray represents the size and the position of the well. F, Foot;V, vibrissae; E, elbow; W, wrist; T, trunk; N, neck;H, hand; D5F, digit 5; X, no response. Coordinates relative to bregma. B, Schematic representation (anterior = 9.7; Paxinos and Watson, 1986) of the most intense c-Fos induction observed in the cortex after picrotoxin application (gray) superimposed on points at which microstimulation elicited movements of the elbow (E) and of the elbow and vibrissae (E/V) at the same position in a different experiment. C, Serial transverse sections through the caudoputamen illustrating the longitudinally extended dorsolateral induction of c-Fos in the striatum after picrotoxin application to the motor cortex. Scale bar, 500 μm.