How Independent Are the Pitch and Interaural-Time-Difference Mechanisms That Rely on Temporal Fine Structure Information?

Abstract

The temporal fine structure (TFS) of acoustical signals, represented as the phase-locking pattern of the auditory nerve, is the major information for listeners performing a variety of auditory tasks, e.g., judging pitch and detecting interaural time differences (ITDs). Two experiments tested the hypothesis that processes for TFS-based pitch and ITD involve a common mechanism that processes TFS information and the efficiency of the common mechanism determines the performance of the two tasks. The first experiment measured the thresholds for detecting TFS-based pitch shifts (Moore and Moore, J Acoust Soc Am 113:977-985, 2003) and for detecting ITD for a group of normal-hearing listeners. The detection thresholds for level increments and for interaural level differences were also measured. The stimulus was a harmonic complex (F0 = 100 Hz) that was spectrally shaped for the frequency region around the 11th harmonic. We expected a positive correlation between the pitch and ITD thresholds, based on the hypothesis that a common TFS mechanism plays a determinant role. We failed to find evidence for a positive correlation, hence no support for the above hypothesis. The second experiment examined whether perceptual learning with respect to detecting TFS-based pitch shifts via training would transfer to performance in other untrained tasks. The stimuli and tasks were the same as those used in the first experiment. Generally, training in the pitch task improved performance in the (trained) pitch task, but degraded the performance in the (untrained) ITD task, which was unexpected on the basis of the hypothesis. No training effect was observed in the other untrained tasks. The results imply that the pitch and ITD processes compete with each other for limited neural resources.

Factors that account for inter-individual variability of lateralization performance revealed by correlations of performance among multiple psychoacoustical tasks

“…Note that for the ITD and Time tasks, the thresholds have been log-transformed. A similar figure has appeared elsewhere (Furukawa et al, 2013 ).…”

“…This study was supported by internal research funding of NTT Corporation. Portions of the data were presented at the International Symposium on Hearing 2012 and have appeared in the conference book (Furukawa et al, 2013 ).…”

Binaural localization of musical pitch using interaural time differences in congenital amusia

“…Similar results have been reported in the visual domain, in which increasing the complexity of the visual-spatial pattern (on screen) had no effect on recall of the letters [ 57 ]. Our results extends previous findings by showing that in the auditory domain, ITD-dependent location and pitch seem to store separately at the working memory level even though both ITD and pitch rely on temporal phase locking mechanism at initial stage of auditory processing [ 5 ]. Such dissociation of working memory storage and retrieval for pitch and binaural ITDs is in line with the notion that musical pitch is stored separately from other perceptual features [ 58 ].…”

“…Phase-locking pattern to the temporal-fine-structure of acoustical signals is also used by the auditory system in determining a sound object’s pitch at the peripheral level, at least for low-frequency tones (i.e., < 5 kHz). Previous research have suggested that efficiency in encoding the temporal-fine-structure of sound waveforms should determine both pitch perception and ITD lateralization performance based on common underlying neural temporal mechanism [ 5 – 8 ].…”

The Early Stage of Perception of Contemporary Art Music: A matter of time

“…While 'short-term memory' generally refers to the simple (and passive) temporary storage of information, 'working memory' is intended to denote a specific type of short-term memory that consists in the maintenance and manipulation of information, taking on an active role and being characteristic of a mutual functioning between storage and processing (Baddeley 2012;Schulze and Koelsch 2012). Moreover, the manifest independent processing of spatial and non-spatial properties of acoustic stimuli in working memory (Alain, Arnott, Hevenor, Graham and Grady 2001;Furukawa, Washizawa, Ochi and Kashino 2013) is evidence that the identification of sound (pitch, spectral and temporal issues) and spatial location (based on interaural time differences) are retained and processed in separate streams. 10 At this primal level, then, temporal features appear to be detached from spatial ones and to betogether with frequency-based informationthe essential dimension of sound configurations present in music and emergent in a sort of (un)storaged domain of our memory.…”