ABSTRACT
This chapter demonstrates that classification of auditory signals in terms of their pitch is an extraordinarily complex process and, argues that the process can conveniently be viewed as a kind of auditory pattern recognition. One line of evidence that simple place or fine-structure theories of pitch are inadequate comes from experiments on the pitch evoked by dichotically presented complex tones. The main problem, which any theory of pitch perception must address, is the invariance of pitch, the fact that many different transformations of the physical stimulus leave its pitch unchanged. The auditory processes that mediate auditory classifications are quite complex and, because the dimensions are purely subjective, research on these processes is difficult. The place theory held that a necessary condition for the perception of pitch is stimulation in the cochlea by the corresponding spectral component. However, in spite of the obvious relationship between the frequency and pitch of a sinusoid, there is no simple physical correlate of pitch.
