We will conduct research and development on the personal computer software package, Neurolucida (copyright), which is intended for use in bioimaging and computer microscopy. Its major application is to light microscopy. It is also applicable to electron microscopy where it would facilitate serial section 3-D reconstructions. It would permit users to acquire, analyze and display three dimensional data that are associated with the mapping and morphometry of neurons in the central and peripheral nervous system. The design concept is based upon image combining computer microscopy. Image data acquisition, based upon image microscopy and the combination of the two can materially assist in applications involving both. Design features to be explored, developed and tested include: (a) applicability to a wide variety of peripherals; computer controlled states, video acquisition subsystems, pointers, displays, printers, plotters, so that Neurolucida can be used with diverse laboratory imaging systems; (b) ability to transfer image data files to existing data base and spread sheet software for increased analytical capabilities; (c) methods for cross referencing video image files to computer graphic display list files of the same structures.