Nerve Signals (IMAGE) University of Copenhagen - Niels Bohr Institute Caption The illustration shows two nerve signals passing through each other completely unhindered. This confirms the theory that the signal is made up of waves in the form of a sound pulse, a soliton, which moves along the nerve membrane. As the sound pulse moves along the nerve pathway, the membrane changes locally from liquid (green) to more solid (red) form. The membrane is slightly compressed, and a voltage pulse is produced by the piezoelectric effect. Credit (Credit: Marie Dyekjær Eriksen, NBI) Usage Restrictions (Credit: Marie Dyekjær Eriksen, NBI) License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.