Figure 5.

STN neuronal firing decreases are primarily cue-locked. A, An example of an A-sort multi-unit whose firing rate decrease is locked to cue presentation. Spike raster (top) and mean firing rate (bottom) aligned to cue presentation. Significant decreases in firing rate (pauses) are shaded for each trial according to their PS index. Trials are sorted by speech production latency; speech production onset for each trial is indicated in green. B, The time interval between cue presentation and pause onset (neuronal response latency) and between pause onset and production onset (neuronal response to production interval) for each trial is correlated against production latency. C, Summary of correlation analyses for all unit recordings with inhibitory responses, showing 3/20 responses were locked to production onset (red circles), 8/20 units were locked to cue presentation (blue circles), and none locked to both cue presentation and production onset (black circles). Open circles in C and indicate B-sorts.