Pitch of noise signals: evidence for a "central spectrum".

Abstract

A review is given of studies dealing with the pitch of signals derived from white Gaussian noise: the pitch of a (monotic) band of noise, the pitch of (dichotic) noise with an interaural phase shift, the monotic and dichotic repetition pitch, and the pitch of two interaurally delayed (uncorrelated) noises. The aim of the paper is to establish the relationship of these pitch phenomena and their connection with the pitch of monaurally presented simple tones (place pitch) and complex tones (periodicity pitch). Therefore, new experiments were performed on the pitch of two noise bands with harmonically related central frequencies, and the pitch of (dichotic) noise with interaural phase shifts at two harmonically related central frequencies, as well as the pitch of band-reject noise. A uniform explanation appears applicable, in correspondence with the theory of the pitch of complex tones, on the basis of the concept of a ’’central spectrum.’’ A simple schematic model of binaural interaction is used to describe the generation of the central spectrum. Pitch data can be accounted for by this model description. The existence region of pitch of dichotic signals is discussed in connection with other binaural functions, like lateralization, binaural beats, and binaural masked level differences.