Behavioral Measures of the Precision of Coding of Interaural Temporal Disparities in Human Listeners
Abstract
The ability to localize sounds, to understand conversation in noisy and/or reverberant environments, and to attend to one of multiple, simultaneous sounds depends heavily on two binaural cues: interaural temporal differences (ITDs) and interaural intensitive differences (IIDs). ITD is the predominant cue, both in terms of human binaural function and in terms of what has been learned about binaural processing via its study. Despite its fundamental role, surprisingly little is known about how the “internal” precision with which ITDs are encoded varies with their magnitude (related to a sound’s azimuthal position) and the frequency region occupied by the sound. With regard to frequency region, it has recently been shown that ITD-processing degrades progressively for higher and higher frequencies when rapid amplitude (envelope) fluctuations convey the ITDs. The proposed experiments and their theoretical analyses, all based on key pilot studies, are designed to provide crucial, yet missing empirical information regarding these fundamental aspects of binaural processing. While such fundamental aspects of ITDprocessing are poorly understood for young, normal-hearing listeners, perhaps more important for societal reasons, is the fact that little is known regarding how degradations of these ITDrelated aspects of binaural hearing may be age-related and/or may be associated with, or result from even “slight” hearing-loss. As highlighted by the recent work of Liberman and his colleagues, important peripheral neural coding deficits may occur even in the absence of measurable losses in audiometric sensitivity (so-called “hidden” hearing-loss) and we believe we have discovered a central, binaural, ITD-related neural manifestation of such deficits. The experiments will rely heavily on the use of novel and innovative stimulus conditions and theoretical analyses developed in the Psychoacoustics Laboratory at the UConn Health Center. The stimuli will be presented in paradigms that promise to be valuable for the diagnosis and evaluation of deficits in binaural hearing that can accompany even slight and/or hidden hearing losses. In addition to gathering empirical data central to furthering our understanding of these issues, the proposal seeks to utilize those data in a manner that provides for their theoretical understanding via a historically successful, comprehensive, quantitative, cross-correlation-based model of binaural hearing.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 12, 2016
- Source ID
- N000141512140
Entities
People
- Leslie Bernstein
Organizations
- Office of Naval Research
- United States Navy
- University of Connecticut