Table 3.

Electrophysiological characteristics of STN neurons in dystonia and Parkinson's disease (PD) subtypes

Factor	Dystonia	Parkinson's Disease (Akinetic–Rigid)	P	Parkinson's Disease (Tremor Dominant)	P
Number of neurons	62	93		50
Mean firing rate, Hz	26.30 (13.6)	35.00 (15.2)	<0.001*	36.70 (15.1)	<0.001*
Burst index	7.20 (4.0)	4.70 (2.5)	<0.001*	4.70 (2.7)	<0.001*
Proportion of discharges in bursts†	0.26 (0.14)	0.19 (0.13)	0.001*	0.20 (0.51)	0.02*
L-statistic	7.10 (1.5)	6.70 (1.7)	0.05	6.80 (1.7)	0.28
Proportion of cells with significant oscillations
0–200 Hz	32.3%	39.8%	0.64	40.0%	0.64
3–30 Hz	6.5%	20.4%	0.05	20.0%	0.05
13–30 Hz	0.0%	6.5%	0.09	6.0%	0.09

Values are means and SD (in parentheses).

^*Denotes statistically significant difference between dystonia and PD subtype identified in the preceding column by Wilcoxon rank-sum test or chi-squared test.

^†As determined using the Poisson “surprise” method.