Electrical activity in the leech nervous system can be studied using a CCD imaging technique

The analysis of the integrative properties of a small nervous system, such as that of many invertebrate animals, requires the study of electrical events originating in different locations of the neuronal network and occurring on different time scales. Even though a detection of electrical signals at a very precise spatial and temporal resolution is at present beyond available experimental techniques, useful information can be obtained from a coarse analysis of the activity in the nervous system.