Figure 3.

Climbing fiber field potentials evoked from the pyramidal tract are depressed by a preceding cuneate stimulation. (A) From left to right, (i) climbing fiber field potential responses in the C3 zone evoked by electrical stimulation in the pyramidal tract (1 pulse, 300 μA, 1 Hz). (ii) Pyramidal tract stimulation preceded (70 ms interstimulus interval) by cuneate stimulation (2 pulses, 20 μA, 1 Hz). (iii) Climbing fiber field response evoked by electrical stimulation in the IO (1 pulse, 30 μA, 1 Hz). (B) Sample histogram showing the amplitude of climbing fiber field responses evoked by pyramidal tract stimulation before during and after a preceding (70 ms) cuneate stimulation (2 pulses, 20 μA, 1 Hz). Each bar represents the average of 5 consecutive responses (bin width, 5 s). Below the histogram, average response profiles for the evoked responses.