This is a proposal for a collaboration with two outstanding Russian investigators to study the principal mechanisms of modulation and integration of neuronal networks involved in the control of feeding behavior in the mollusc Clione limacina. This preparation serves as a model system for posing general questions concerning the modulation and control of motor output and behavior by the central nervous system. The mollusc central nervous system is particularly favorable for this study because neuronal networks involved in the control of feeding behavior have been identified. The main idea is that neuronal networks are not rigidly wired formed by fixed connections between neurons, but are flexible polyfunctional structures that generate a broad range of motor outputs. The flexibility of the networks is determined by nervous and hormonal inputs that modify the properties of neurons and their connecting synapses. The properties of single neurons, synaptic connections and the feeding network will be studied by recording the responses of neurons during feeding behavior in the presence and absence of various neuromodulators found in molluscs.***//
