Automatic frequency-shift detection in the auditory system: A review of psychophysical findings.
Neuroscience. 2017-09-01; :
Read on PubMed
1. Neuroscience. 2017 Sep 1. pii: S0306-4522(17)30621-8. doi:
10.1016/j.neuroscience.2017.08.045. [Epub ahead of print]
Automatic Frequency-Shift Detection in the Auditory System: A Review of
Demany L(1), Semal C(2).
(1)Institut de Neurosciences Cognitives et Intégratives d’Aquitaine, CNRS and
Université de Bordeaux (UMR 5287), Bordeaux, France. Electronic address:
(2)Institut de Neurosciences Cognitives et Intégratives d’Aquitaine, CNRS and
Université de Bordeaux (UMR 5287), Bordeaux, France.
The human brain has the task of binding successive sounds produced by the same
acoustic source into a coherent perceptual stream, and binding must be selective
when several sources are concurrently active. Binding appears to obey a principle
of spectral proximity: pure tones close in frequency are more likely to be bound
than pure tones with remote frequencies. It has been hypothesized that the
binding process is realized by automatic “frequency-shift detectors” (FSDs),
comparable to the detectors of spatial motion in the visual system. In 2005, this
hypothesis was supported by a psychophysical study showing that human listeners
are able to identify the direction of a frequency shift between two successive
pure tones while the first of these tones is not audible individually due to
informational masking by other tones presented synchronously. A number of
variants of this study have been performed since 2005, in order to confirm the
existence of FSDs, to characterize their properties, and to clarify as far as
possible their neural underpinnings. The results obtained up to now suggest that
the working of the FSDs exploits an implicit sensory memory which is powerful
with respect to both capacity and retention time. Tones within chords can be
perceptually enhanced by small frequency shifts, in a manner suggesting that the
FSDs can serve in auditory scene analysis not only as binding tools but also, to
a limited extent, as segregation tools.
Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.