Locomotion in all segmented animals consists of a repeated series of movements that are metachronously coordinated in different segments of the animal's body. The objectives of the work to be performed by Dr. Brian Mulloney are to describe the structure, integrative properties and synaptic organization of the neurons that control the metachronous movements of one set of segmental limbs, the abdominal swimmerets of the crayfish and to describe how the ganglia in which they occur are organized. These experiments will allow us to compare the characteristics of spiking intersegmental coordinators and non.spiking bilateral local coordinators, and to see if the non.spiking neurons play roles fundamentally different from those of the spiking interneurons in the generation of these movements. They will test an hypothesis about the properties of neurons that synchronize bilateral pattern generating circuits. They will discover the intersegmental circuits that coordinate different limbs metachronously, and permit us to compare these circuits with functionally equivalent circuits in other animals. This work is important because it will yield more knowledge which is missing about coordinated movements and may supply valuable information regarding spinal reflexes in man.
