Figure 1.

A, Periocular-evoked LFP recordings made in an awake rabbit (average of 20 trials). Two pairs of periocular stimuli (3 ms interval) are presented 40 ms apart (arrows). Mossy fiber potentials (MF) follow the second pair of stimuli, whereas a longer-latency climbing fiber component (CF) is markedly depressed. B, For the same trace as in A, evoked field potentials from the first pair and second pair of stimuli (solid and dotted lines, respectively) are overlaid on an expanded time base. The mossy fiber potentials (MF) show two peaks 3 ms apart, representing activity evoked by each pulse in the paired stimulus: the later peak dominates after the first stimulus pair (solid line), whereas the earlier peak is more prominent after the second pair (dotted line), indicating a facilitated response to the first pulse. In contrast, the climbing fiber potential (CF) is depressed after the second pair. C, An example of covarying, congruent MFPs and CFPs, shown for the same electrode track in which the activity in A and B was recorded. The traces show the average periocular-evoked LFPs (20 trials) to the first stimulus pair only, at seven consecutive depths in the electrode track (dorsal to ventral, top to bottom; 200 μm steps; calibration: 10 ms, 100 μV). The trace marked with a star is the same as that illustrated in A and B.