Science image (IMAGE) Salk Institute Caption The neurons of the worm function differently when tasting salt. Each circle represents a neuron, and the connections between the circles are synapses. The scientists used graph theory to group some neurons into modules, which are identified by their colors. The number of modules was reduced to 5 (from 7) when the salt stimulus was presented to the worm. This signifies that these neurons are particularly important when the animal tastes salt. Credit Salk Institute Usage Restrictions with credit and related coverage. License Original 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.