Blind people are more sensitive than sighted people to binaural sound-location cues, particularly inter-aural level differences.

Blind people are more sensitive than sighted people to binaural sound-location cues, particularly inter-aural level differences.
Hear Res. 2015 Sep 30;
Authors: Nilsson ME, Schenkman BN
Abstract
Blind people use auditory information to locate sound sources and sound-reflecting objects (echolocation). Sound source localization benefits from the hearing system's ability to suppress distracting sound reflections, whereas echolocation would benefit from "unsuppressing" these reflections. To clarify how these potentially conflicting aspects of spatial hearing interact in blind versus sighted listeners, we measured discrimination thresholds for two binaural location cues: inter-aural level differences (ILDs) and inter-aural time differences (ITDs). The ILDs or ITDs were present in single clicks, in the leading component of click pairs, or in the lagging component of click pairs, exploiting processes related to both sound source localization and echolocation. We tested 23 blind (mean age = 54 y), 23 sighted-age-matched (mean age = 54 y), and 42 sighted-young (mean age = 26 y) listeners. The results suggested greater ILD sensitivity for blind than for sighted listeners. The blind group's superiority was particularly evident for ILD-lag-click discrimination, suggesting not only enhanced ILD sensitivity in general but also increased ability to unsuppress lagging clicks. This may be related to the blind person's experience of localizing reflect...

Source: Hearing Research - September 30, 2015 Category: Audiology Authors: Nilsson ME, Schenkman BN Tags: Hear Res Source Type: research