The broad objective is to focus the latest techniques of the physical sciences and modern technology on the solution of problems encountered in studies of the development, structure, function, and dysfunction of the nervous system, the neuromuscular system, and the communicative system. The School of Medicine and the Applied Physics Laboratory will collaborate to provide the stimulus, expertise, and environment to achieve this. There are four specific research projects and one core project. In the first project, a real time, multi-channel, multi-unit neural spike separation system will be developed. Multiple electrode neuron recordings presently require continuous human monitoring and intervention. This is difficult when the signal-to-noise ratio is small, the signal amplitudes are variable, or more than one neuron with similarly shaped action potentials are present on a channel. To solve this problem, the proposed system will automatically track slowly varying waveshapes and resolve spike superpositions. The second project will develop a device for presentation of a visual target in 3-D space. This system will be used to determine the neural mechanisms involved in eye-hand tracking of visual objects moving in space. The third project will develop a mechanical stimulator specifically designed for the study of the neurophysiological and psychophysical mechanisms of pain sensation. Presently available devices are designed for the study of touch, not pain. This stimulator will deliver precisely controlled force and/or displacement stimuli well into the noxious range. In the fourth project, a hand-held fiber-optic based interferometer system will be developed for measuring motion in the middle ear. This will allow intraoperative assessment of middle ear function during prosthetic surgery. The purpose of the core function is to facilitate the development and feasibility testing of new concepts for future neurosensory projects.