Resolving front-back ambiguity with head rotation: the role of level dynamics

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

Abstract

Making small head movements facilitates spatial hearing by resolving front-back confusions, otherwise common in free field sound source localization. The changes in interaural time difference (ITD) in response to head rotation provide a robust front-back cue, but whether interaural level difference (ILD) can be used as a dynamic cue is not clear. Therefore, the purpose of the present study was to assess the usefulness of dynamic ILD as a localization cue. The results show that human listeners were capable of correctly indicating the front-back dimension of high-frequency sinusoids based on level dynamics in free field conditions, but only if a wide movement range was allowed (±40∘). When the free field conditions were replaced by simplistic headphone stimulation, front-back responses were in agreement with the simulated source directions even with relatively small movement ranges (±5∘), whenever monaural sound level and ILD changed monotonically in response to head rotation. In conclusion, human listeners can use level dynamics as a front-back localization cue when the dynamics are monotonic. However, in free field conditions and particularly for narrowband target signals, this is often not the case. Therefore, the primary limiting factor in the use of dynamic level cues resides in the acoustic domain behavior of the cue itself, rather than in potential processing limitations or strategies of the human auditory system.

Details

Original languageEnglish
Pages (from-to)196-207
Number of pages12
JournalHearing Research
Volume377
Early online date2019
Publication statusPublished - 1 Jun 2019
MoE publication typeA1 Journal article-refereed

    Research areas

  • active localization, head rotation, front-back ambiguity, binaural cues, directional bands, acoustic bright spot, Head rotation, Active localization, Front-back ambiguity, Directional bands, Acoustic bright spot, Binaural cues

ID: 32944094