This project is intended to develop techniques and instrumentation for the acquisition and processing of neuroelectric signals from the center and peripheral nervous systems in acute and chronic neurophysiological preparations. Because of this Laboratory's continuing interest in sensorimotor neural activity during unrestrained movements, the project also includes development and fabrication of chronically implantable microelectrodes, mechanical transducers, catheters, and connectors. Due to the Laboratory's on-going interests in doing research on isolated preparations such as the spinal cord of chicken embryos and rats, a significant amount of work has been devoted to improving techniques associated with electrical recording, stimulation, and real-time fluorescence microscopy in these preparations. Several projects which have been associated with the visual prosthesis feasibility studies, normally reported on under this project number, are now being reported under project Z01 NS 02857-04 LNLC. These projects are referenced as such throughout this report. There are also several other new projects which would normally be listed under this project number but are now listed under the recent visual prosthesis project number.