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

Figure 2

Example of an EMG signal used for RT measurement. The participants were instructed to start and quit the voluntary isometric muscle contraction as quickly as possible when they recognized an auditory beep “on” and “off.” RTi (delay in initiation) was defined as the time interval between the onset of the beep and the onset of EMG contraction signal. RTt (delay in termination) was defined as the time interval between termination of the beep and termination of the EMG signal.