Creation of Pitch through Binaural Interaction

This paper is an investigation of the phenomenon which was observed by Huggins in 1953. Huggins found that a binaural stimulus gives a fairly clear perception of pitch although the separate stimuli to the two ears give no such perception. The basic stimulus consists of white noise introduced into one ear while the same white noise, phase transformed in a narrow band of frequencies, is introduced into the other ear. A practiced subject listening to this stimulus reports a faint pitch quality which is judged to sound about the same as narrow-band filtered noise. A forced-choice technique was used in which six subjects were asked to judge the direction of the pitch change when the frequency band over which the phase shift occurs was changed. The control consisted of the same stimulus presented to the two ears. Data are presented indicating the relationship between the percent of correct judgments and the three experimental variables, frequency, band width, and intensity level.