Sound localization in the horizontal plane primarily depends on the interaural time difference (ITD) and interaural intensity difference (IID). When sounds with identical ITD or IID are presented to both ears, the sound image is lateralized to the side receiving the earlier or louder stimulus within the head. Currently, ITD and IID discrimination abilities are separately measured with a commercially available self recording apparatus.
In this review, the history and basic science of sound localization is discussed in detail. Moreover, for future clinical application, sound lateralization abilities of patients with peripheral hearing loss, brain stem disorders, and auditory cortex disorders are described pertaining to discrimination of ITD or IID separately using a self recording sound lateralization system.
