The effect of head turning on sound localization with hearing-aid satellites
We investigated whether an eccentric head orientation influences localization performance of hearing-aid (HA) users with in-the-ear (ITE) and behind-the-ear (BTE) HAs. A localization experiment was conducted with three static head orientations, ±30° and 0°, for a 0° torso orientation. Fourteen sound directions were tested for each head orientation using a short broadband-noise pulse-train stimulus. The perceived sound direction was indicated with a light pointer. Sounds perceived from behind could also be displayed at the mirrored frontal position. Results from nine normal hearing participants show that an off-center head orientation leads to an overestimation of the extent of laterality for sound sources on the side, away from the head center. Preserving pinna cues (e.g., by ITE microphone position) is beneficial for the localization performance in the frontal plane and reduces the negative influence of off-center head-orientations. For rear sound directions, localization errors increase strongly for BTEs because of frequent front-back reversals. However, an eccentric head orientation tends to decrease the amount of front-back reversals. In summary, we found that localization performance is affected by the microphone position, but an eccentric head orientation is beneficial to resolve front-back confusions with HAs.The talk will be given in German.