PATTERN GENERATION

Central pattern generators are neuronal ensembles capable of producing the basic spatiotemporal patterns underlying 'automatic' movements (e .g. locomotion, respiration, swallowing and defense reactions), in the absence of peripheral feedback. Different experimental approaches, fr om classical electrophysiological and pharmacological methods to molec ular and genetic ones, have been used to understand the cellular and s ynaptic bases of central pattern generator organization and reconfigur ation of generator operation in behaviorally relevant contexts. Recent ly, it has been shown that the high reliability and flexibility of cen tral pattern generators is determined by their redundant organization. Everything that is crucial for generator operation is determined by a number of complementary mechanisms acting in concert; however, variou s mechanisms are weighted differently in determining different aspects of central pattern generator operation.