Relation between lateralization and loudness in asymmetrical hearing losses.

The purpose of these experiments was to study the role of interaural intensity and loudness differences in median-plane lateralization. Observers who either wore an earplug in one ear or had an asymmetrical hearing loss varied the intensity of simultaneous tone bursts at the two ears to center a sound image inside their heads. Hard-of-hearing Ss with conductive and cochlear losses centered the tone bursts by setting them somewhere between equal intensity and equal loudness at the two ears. Although Ss with the simulated loss first centered the tones on the basis of equal loudness, after several days of wearing the ear plug, they centered in the same manner as observers with long-term hearing losses.