Axonal recordings from the lateral lemniscus: structure and function.

Sounds at the two ears can differ in two basic ways: in intensity and in time. Interaural level differences (ILDs) arise from a shadowing effect by the head so that sounds are more intense at the ear closest to the sound source. Interaural time differences (ITDs) arise from unequal pathlengths that the sound must travel to the near and the far ear. ILDs and ITDs are measured by the brain and convey important information for spatial hearing, including the localization of sound sources and the detection of signals in a noisy environment. These abilities are often compromised in people with hearing problems.