In EMG biofeedback, what is the effect of wider spacing of electrodes?

In EMG biofeedback, what is the effect of wider spacing of electrodes?

• A. Decrease volume monitored
• B. Increase crosstalk
• C. Monitor more volume of muscle
• D. Decrease signal amplitude

Answer: (C)

Wider spacing between surface electrodes expands the region of muscle from which the EMG signal is sampled. Because the electrical signals propagate through tissue, electrodes farther apart pick up activity from a larger area and more motor units, so you monitor a bigger volume of muscle. This broader coverage can improve detection of widespread activation, though it may come with tradeoffs like increased crosstalk from neighboring muscles and reduced spatial specificity.

Wider spacing between surface electrodes expands the region of muscle from which the EMG signal is sampled. Because the electrical signals propagate through tissue, electrodes farther apart pick up activity from a larger area and more motor units, so you monitor a bigger volume of muscle. This broader coverage can improve detection of widespread activation, though it may come with tradeoffs like increased crosstalk from neighboring muscles and reduced spatial specificity.