Fig. 6.

Example of the effects of a microinjection of MK-801 (20 mm, 0.2 μl) into the left SRD (A) on the responses of a neuron recorded in the right VMl (B) to supramaximal percutaneous electrical stimulation of the four limbs (C). In each set of poststimulus histograms, thetop one represents the control, themiddle one was obtained 5–10 min after the microinjection, and the bottom one 30–35 min after the injection. Note that the responses elicited from any limb were depressed by the microinjection. Abbreviations as in Figures 1and 5.