Question

How does signal delay and triggering unit help in EMG?

(a) It delays the incoming signal and allows the current signal to be processed properly

(b) The delayed signals keep the system working for a longer time

(c) The delayed signal is actually signal acquired from individual muscles

(d) The delayed signal provides clarity in processing

I have been asked this question during an online interview.

This interesting question is from Electromyography topic in section Diagnostic Investigation in Neurology and Cardiology of Clinical Science

Answer 1

Right choice is (c) The delayed signal is actually signal acquired from individual muscles

The explanation: The signal delay and trigger unit of EMG is used to examine signal from individual muscle fibers. For this purpose, there is a special electrode of 25 micron diameter which has 14 needles like pick up surfaces.  In order to receive and analyze signals properly, a delaying sweep is used. This allows for the signal to be taken from every needle individually, one at a time. This allows for better processing of the signal as well.