Azimuthal sound source localization of various sound stimuli under different conditions

To evaluate azimuthal sound-source localization performance under different conditions, with a view to optimizing a routine sound localization protocol. Two groups of healthy, normal-hearing subjects were tested identically, except that one had to keep their head still while the other was allowed to turn it. Sound localization was tested without and then with a right ear plug (acute auditory asymmetry) for each of the following sound stimuli: pulsed narrow-band centered on 250Hz, continuous narrowband centered on 2000Hz, 4000Hz and 8000Hz, continuous 4000Hz warble, pulsed white noise, and word (“lac” (lake)). Root mean square error was used to calculate sound-source localization accuracy. With fixed head, localization was significantly disturbed by the earplug for all stimuli (P