Figure 3.

Preservation of perimovement firing pattern with STN-DBS. A, Perimovement histograms of a unit that showed strong preservation of DBS-off firing pattern (increase in firing rate ∼20 ms before movement onset, gray trace), during DBS-on (black trace). Both histograms are aligned to movement onset (time 0). B, Perimovement histograms, constructed as in A, of exemplar pallidal cell demonstrating loss of significant perimovement activity during DBS-on. C, Scatter plot of bin-by-bin firing rates from the DBS-on condition (A, black trace) plotted versus those from the DBS-off condition (A, gray trace). Perimovement firing rates of this cell in the DBS-off and DBS-on state were highly correlated (results from “off/on-ρ” Spearman correlation inset and solid line) indicating a preservation of the timing and shape of perimovement activity throughout stimulation. D, Scatter plot (following the conventions of C) of the neuron shown in B. The perimovement firing rates of this neuron (in the DBS-off and DBS-on state) were not significantly correlated, indicating a loss of perimovement activity during stimulation. E, Population summary of the off/on-ρ values reflecting the degree to which DBS-off perimovement activity was preserved during STN-DBS (116 of 176, 66% black bars; gray bars: significant negative off/on-ρ values). F, Strong entrainment of spiking to DBS reduced the preservation of movement-related activity (off/on-ρ). Filled circles represent significant off/on-ρ value (as reported in E). Open circles represent nonsignificant off/on-ρ value. Δ indicates the neuron shown in Fig. 2Ai. ▿ indicates the neuron shown in Fig. 2Aii. G, H, The degree to which movement-related activity was preserved during DBS (off/on-ρ) correlated with the effects of DBS on resting entropy (ΔEntropy) (G) but not baseline firing rate (ΔFR) (H). G, Inset, legend for the symbol shapes and colors used in G and H. sig, Significant; ns, nonsignificant. Dashed lines indicate 95% confidence interval of correlation.