Accession Number : ADA326164

Title :   Demodulation Processes in Auditory Perception.

Descriptive Note : Final rept. 1 Jun 93-31 Dec 96,

Corporate Author : OHIO STATE UNIV COLUMBUS DEPT OF SPEECH AND HEARING SCIENCE

Personal Author(s) : Feth, Lawrence

PDF Url : ADA326164

Report Date : 01 JUN 1997

Pagination or Media Count : 8

Abstract : The long range goal of this project was the understanding of human auditory processing of information conveyed by complex, time varying signals such as speech, music or important environmental sounds. Our work was guided by the assumption that human auditory communication is a 'modulation - demodulation' process. That is, we assume that sound sources produce a complex stream of sound pressure waves with information encoded as variations (modulations) of the signal amplitude and frequency. The listener's task then is one of demodulation. Much of past psychoacoustic work has been based in what we characterize as 'spectrum picture processing.' Complex sounds are Fourier analyzed to produce an amplitude by frequency 'picture' and the perception process is modeled as if the listener were analyzing that spectral picture. This approach leads to studies such as 'profile analysis' and to the power spectrum model of masking. Our approach leads us to investigate time varying, complex sounds. We refer to them as dynamic signals and we have developed auditory signal processing models to help guide our experimental work.

Descriptors :   *SPEECH, *DEMODULATION, *VOICE COMMUNICATIONS, *AUDITORY SIGNALS, *AUDITORY PERCEPTION, SIGNAL PROCESSING, FREQUENCY, HUMANS, POWER SPECTRA, SOUND WAVES, MODULATION, AMPLITUDE, PICTURES, SOUND PRESSURE, TIME SIGNALS, MASKING, PSYCHOACOUSTICS, MUSIC, SOUND GENERATORS.

Subject Categories : Acoustics
      Voice Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE