Assessment of the role of the cochlear latency effect in lateralization of click sounds in humans

Ozmen B., Ungan P.

PSYCHOPHYSIOLOGY, cilt.46, sa.4, ss.797-806, 2009 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 46 Sayı: 4
  • Basım Tarihi: 2009
  • Doi Numarası: 10.1111/j.1469-8986.2009.00828.x
  • Dergi Adı: PSYCHOPHYSIOLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Social Sciences Citation Index (SSCI), Scopus
  • Sayfa Sayıları: ss.797-806
  • Hacettepe Üniversitesi Adresli: Evet

Özet

Interaural time and intensity disparities (ITD and IID) are the two cues to sound lateralization. "Time-only'' hypothesis claims that an IID is first converted to an interaural afferent delay (Delta t), and is then processed by the central ITD mechanism, rendering a separate IID processor unnecessary. We tested this hypothesis by assessing the contribution of the cochlear latency effect to the psychophysical ITD/IID trading ratio. Auditory brainstem responses (ABRs) were used to measure the interaural afferent delays (Delta ts) that developed with a 20/sec dichotic click train used in the trading experiment. Except for small IIDs at low loudness levels, the physiological Delta t delay produced by an IID was significantly smaller than the ITD psychophysically traded for the same IID. We concluded that the cochlear latency effect alone cannot explain the psychophysical ITD/IID trading ratios and a separate IID mechanism must be involved.