A CENTRAL SPECTRUM MODEL - A SYNTHESIS OF AUDITORY-NERVE TIMING AND PLACE CUES IN MONAURAL COMMUNICATION OF FREQUENCY-SPECTRUM

A probabilistic psychophysical model for monaural communication from the auditory nerve to the brain is given in the form of a tonotopic display of stimulus spectrum, termed central spectrum. The model builds upon prior research demonstrating the potential of neutral timing cues from the auditory nerve for conveying information on complex spectra, and was designed to meet the quantified demands of the psychophysics of frequency measurement. The central spectrum magnitude at each frequency is determined by the response of the auditory-nerve fiber with characteristic frequency matching that frequency. An interval histogram from each fiber is passed through a filter matched to the characteristics frequency of the fiber. This output versus characteristic frequency defines the central spectrum. Detailed analysis psychophysical properties of frequency in discrimination and perodicity pitch experiments. Psychophysical models based upon the central spectrum model followed by optimum probabilistic pattern recognition are potentially relevant for predicting human communication limits in response to arbitrary sounds of speech and music.