Psychophysical studies of complex auditory patterns and their dependence on stimulus information, attention, and learning, as well as on tactile and electrocutaneous stimulation for use in non-auditory sensory aids. Electrophysiological studies of nonlinearities in the response of the inner ear as well as of clinical phenomena revealed in evoked responses obtained from humans. Further anatomical, physiological and behavioral studies directed to understanding the mechanism associated with hearing loss following noise exposure. Behavioral studies of speech perception and psychoacoustic responses to speech-like sounds in animals and humans. Engineering development of computer systems for speech and other complex-sound analysis and for laboratory procedures, and of hearing-aid systems that incorporate different gain characteristics in different frequency bands. Studies on auditory training procedures for young deaf children and of developmental scales or language development. BIBLIOGRAPHIC REFERENCES: The audiometric utility of brain stem responses to low-frequency sounds. H. Davis, S.K. Hirsh. Audiology 15: 181-195, 1976. A role for the cochlear microphonic: Suppression of auditory action potentials? D.H. Eldredge. In: S.K. Hirsh et al. (Eds.) Hearing and Davis. St. Louis, MO: Washington University Press, pp. 37-52, 1976.