Quantitative Electromyographic Analysis of Reaction Time to External Auditory Stimuli in Drug-Naïve Parkinson’s Disease

Table 1

Differences in reaction time between Parkinson’s disease patients (𝑛=31) and healthy controls based on independent 𝑡-tests (𝑛=15) and paired 𝑡-test comparison of the reaction times between the more- and less-affected side for all patients.

		Control (𝑛=15)	PD (𝑛=31)	𝑃 value	Within PD group (𝑛=30)		𝑃 value
					More-affected side; (Rt 19, Lt 11)	Less-affected side; (Rt 11, Lt 19)
RTi	Wrist flexion	198.8±28.2	264.2±79.9	<0.001**	287.7±93.9	244.1±61.3	0.001**
	Wrist extension	194.9±33.5	253.8±85.7	<0.001**	271.6±100.4	239.0±68.1	0.01**
	Ankle flexion	209.7±27.8	265.0±92.0	<0.001**	284.2±11.8	248.5±55.7	0.021*
RTt	Wrist flexion	242.4±31.6	317.8±75.0	<0.001**	333.0±79.2	303.5±68.7	0.024*
	Wrist extension	236.5±27.2	297.5±63.3	<0.001**	312.9±68.4	280.8±55.9	0.012*
	Ankle flexion	261.8±21.6	306.1±68.4	<0.001**	309.6±78.1	303.6±61.0	0.603

∗The mean difference is significant at the 0.05 level.
**The mean difference is significant at the 0.01 level.
Data are presented as mean ± SD (msec).
PD: Parkinson’s disease; RTi: reaction time (initiation delay of muscle contraction); RTt: reaction time (termination delay of muscle contraction).