Figure 5 - Effect of electrical nerve stimulation on electrical response and tension of UES closing muscles.

The effects of electrical nerve stimulation on electrical responses are indicated in the left panels and on tension in the right panels, whereas the effects of stimulation of the PEN are indicated in the top panels and of RLN stimulation in the bottom panels. Note that PEN stimulation had a large effect on both electrical response and tension of the CP, whereas RLN stimulation had a small effect on CP electrical response but no effect on CP tension. Therefore, electrical stimulation of the RLN can produce an electrical response on the CP that has no effect on muscle tension and is probably due to spread of electrical current from the RLN or laryngeal muscles underlying the CP.