Table 1. Database and basic properties of neurons.
| Measure | GPi | VLa | ||||
|---|---|---|---|---|---|---|
| NHP G | NHP I | Total | NHP G | NHP I | Total | |
| Number of units | 105 | 104 | 209 | 66 | 119 | 185 |
|
Mean rate at rest (sp/s [SD]) |
70.8 (26.0) | 69.4 (29.9) | 70.1 (27.9) | 14.8 (10.8) | 14.2 (11.4) | 13.5 (10.5) |
|
Action potential width (ms min-to-max [SD]) |
0.24 (0.06) | 0.24 (0.11) | 0.24 (0.09) | 0.46 (0.22) | 0.53 (0.19) | 0.50 (0.21) |
| Mvt-responsive neurons [number (%)] | 102 (97) | 104 (100) | 206 (99) | 58 (87.9) | 105 (88.2) | 163 (88.1) |
| Mvt-related responses | 187 | 201 | 388 | 110 | 216 | 326 |
| Increase only | 109 | 80 | 189 (48.7) | 81 | 132 | 213 (65.3) |
| Decrease only | 33 | 37 | 70 (18.0) | 20 | 57 | 77 (23.6) |
| Polyphasic increase first | 29 | 37 | 66 (17.0) | 5 | 13 | 18 (5.5) |
| Polyphasic decrease first (number [%]) | 16 | 47 | 63 (16.2) | 4 | 14 | 18 (5.5) |
| Increases (proportion of all detected changes*) | 66.4% (154/232) | 57.5% (164/285) | 61.5% (318/517) | 75.6% (90/119) | 65.4% (159/243) | 68.8% (249/362) |
| Mean integrated change (sp [SD] × 103) | 4.38 (10.0) | 3.41 (11.4) | 3.89 (10.7) | 3.24 (7.07) | 0.96 (3.61) | 1.75 (5.19) |
| Response latencies (ms relative to reach onset) | ||||||
| Increases (medians) | −77.5 | −74 | −76 | −87.5 | −88.5 | −88 |
| Decreases (medians) | 31 | −52.5 | −31.5 | −117 | −89 | −95.5 |
Bold: significant difference between GPi and VLa neurons by Wilcoxon rank sum or chi-squared tests.
* For proportion of increases, biphasic responses are counted twice to account for the simultaneous presence of an increase and decrease in firing.
Abbreviations: GPi, globus pallidus-internus; max, maximum; min, minimum; Mvt, movement; NHP, nonhuman primate; sp, spikes; VLa, ventrolateral anterior nucleus