Effect of Intensity Duration and Spectrum on the Perception of Two-Element Auditory Sequences

Abstract

Recently, interest has been shown in the perception of acoustic stimuli embedded in a sequence of sounds, particularly in relation to studies of speech perception. The particular question we have asked is: How is the perception of a given sound influenced by the physical parameters of a sound adjacent to it in temporal sequence? In the present experiments each stimulus comprises two components separated by a 10 msec gap; each component is a noise of specified band width, center frequency, intensity, and duration. Two of these stimuli are chosen as standards in a given experiment, and listeners are required to place other stimuli into one of the two categories typified by the standard stimuli. In a typical experiment, each of the standard stimuli consisted of two components that were equal in all respects except duration. After hearing these standards, subjects were required to categorize each of a series of ambiguous stimuli in which relative duration and intensity were manipulated. Results demonstrated a trading between intensity and duration, although the relations did not follow a simple pattern. In other experiments using different pairs of stimuli as standards, we have studied the influence of noise center frequency and band width as experimental variables. [This work was supported in part by the U. S. Army (Signal Corps), the U. S. Air Force (Office of Scientific Research, Air Research and Development Command), and the U. S. Navy (Office of Naval Research); and in part by the National Science Foundation.]