Auditory streaming and the building of timbre.
Albert S. Bregman, Steven A. Pinker · Canadian Journal of Psychology/Revue Canadienne de Psychologie · 1978
In a natural environment, the auditory system must analyse an incoming wave train to determine two things: (a) which series of frequency components arose over time from the same source and should be integrated into a sequential stream, and (b) which set of simultaneous components arose from one source and should be fused into a timbre structure. A set of experiments was performed in which subject judged the stream organization and the timbre of a repeating cycle formed by a pair of more or less synchronous pure tones, B and C, and a preceding pure tone, A, whose frequency was varied in its proximity to that of the upper tone of the BC pair. These experiments demonstrated that fusion and sequential organization of streams are carried out using two sorts of information which compete to determine the best perceptual description of the input. Proximal frequencies between sequential components promotes a sequential organization and the simultaneity of onset of frequency components promotes perceptual fusion.