9601063 Roye The principal investigator in this study will use an invertebrate model (the commercially important blue crab) to study nerve cells in a central nervous system that organize a well defined behavior occurring in a single body appendage (withdrawal of the first segmental appendage, the antennule). He will use appropriate modern techniques (intracellular recording, fluorescent dyes injection, etc.) to identify and map each cell involved to the production of this particular behavior. A great benefit of the model used is that each cell in the neural network under investigation can be identified as a unique entity present in all blue crabs. Studies of this type are important if a real understanding of how the behaviors generally (including those of man) are created by brain neural networks. The potential value of a complete understanding of the form and function of neural networks that produce behavior is enormous, with implication for computer design, robot fabrication, etc.