The Effect of Noise in One Ear upon the Loudness of Speech in the Other Ear

Although a sufficiently intense noise in one ear will mask speech heard in the contralateral ear a weaker noise has the opposite effect: it enhances the loudness of speech heard in the other ear. Procedure: one earphone is used to introduce speech at a constant intensity into one ear. Another earphone introduces a white noise into the other ear. The listener first listens to the speech heard monaurally (ear 1) with no noise in the contralateral ear (ear 2). If noise is now introduced into ear 2, the loudness of speech heard in ear 1 increases. Most listeners report a change in the localization of the speech: it is localized nearer to the center of the head when noise is introduced into the opposite ear. This paper concerns these phenomena.