This is a multidisciplinary project dedicated to the advancement of knowledge in neurotology to be accomplished through a balanced endeavor of basic and clinical research. The work is directed toward the application of modern technology to the development of new diagnostic methods and the acquisition of the fundamental information necessary for the solution of neurotologic problems. These new techniques are often being developed as a result of experiences obtained in animal research. The proximity of laboratories and the daily interdisciplinary cooperation make feasible the application of concepts and techniques developed through basic research. The objective of the basic research program is to study the function of the inner ear receptor organs, the visual system, and various central nervous system elements which together are responsible for the maintenance of equilibrium and orientation. The clinical research program is concerned with the diagnosis and treatment of disorders that cause dizziness, vertigo, dysequilibrium, ataxia, and other impairments of visual- oculomotor function. One of the main goals of this project is the development of objective and reliable quantitative methods for the functional vestibular evaluation of normal subjects and patients with neurotologic disorders. In addition to the immediate clinical benefits, we hope to gain further knowledge of the higher-order functions of the brain. Research on human subjects is the most important source of information on these sensory and motor functions. Animal models can complement but cannot replace patients as subjects for study of vestibular disorders. The investigators of this project are aware of the broader implications of their research and stimulated by the challenge of this complex task.