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

Table 3

Comparison of RT values between the three Parkinson’s disease groups classified according to Hoehn and Yahr stage.

		Mean latency ± SD (msec)			𝑃 value
		H&Y stage 1; (𝑛=7, 14 limbs)	H&Y stage 2; (𝑛=16, 32 limbs)	H&Y stage ≥2.5; (𝑛=8, 16 limbs)
RTi	Wrist flexion	247.9±91.0	241.5±49.2	323.1±94.3	0.040*
	Wrist extension	224.0±36.1	224.5±39.5	338.5±12.3	<0.001**
	Ankle flexion	214.6±23.7	259.3±76.5	320.4±12.7	0.005*
RTt	Wrist flexion	281.8±48.8	310.6±60.2	361.2±99.4	0.058
	Wrist extension	276.2±40.6	285.3±46.3	340.5±88.0	0.001**
	Ankle flexion	289.8±26.8	289.4±53.4	353.8±96.3	0.011*

∗The mean difference is significant at the 0.05 level.
**The mean difference is significant at the 0.01 level.
H&Y stage: Hoehn and Yahr stage; RTi: reaction time (initiation delay of muscle contraction); RTt: reaction time (termination delay of muscle contraction); msec: milliseconds.