Lancaster EPrints

Representations of pitch and slow modulation in auditory cortex

Barker, Daphne and Plack, Christopher J. and Hall, Deborah A. (2013) Representations of pitch and slow modulation in auditory cortex. Frontiers in Systems Neuroscience, 7. ISSN 1662-5137

[img]
Preview
PDF (fnsys-07-00062) - Published Version
Available under License Creative Commons Attribution.

Download (1019Kb) | Preview

    Abstract

    Iterated ripple noise (IRN) is a type of pitch-evoking stimulus that is commonly used in neuroimaging studies of pitch processing. When contrasted with a spectrally matched Gaussian noise, it is known to produce a consistent response in a region of auditory cortex that includes an area antero-lateral to the primary auditory fields (lateral Heschl's gyrus). The IRN-related response has often been attributed to pitch, although recent evidence suggests that it is more likely driven by slowly varying spectro-temporal modulations not related to pitch. The present functional magnetic resonance imaging (fMRI) study showed that both pitch-related temporal regularity and slow modulations elicited a significantly greater response than a baseline Gaussian noise in an area that has been pre-defined as pitch-responsive. The region was sensitive to both pitch salience and slow modulation salience. The responses to pitch and spectro-temporal modulations interacted in a saturating manner, suggesting that there may be an overlap in the populations of neurons coding these features. However, the interaction may have been influenced by the fact that the two pitch stimuli used (IRN and unresolved harmonic complexes) differed in terms of pitch salience. Finally, the results support previous findings suggesting that the cortical response to IRN is driven in part by slow modulations, not by pitch.

    Item Type: Journal Article
    Journal or Publication Title: Frontiers in Systems Neuroscience
    Additional Information: © 2013 Barker, Plack and Hall. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
    Uncontrolled Keywords: pitch ; iterated ripple noise ; IRN ; planum temporale ; Heschl's gyrus ; spectro-temporal modulation
    Subjects:
    Departments: Faculty of Science and Technology > Psychology
    ID Code: 67997
    Deposited By: ep_importer_pure
    Deposited On: 12 Dec 2013 13:21
    Refereed?: Yes
    Published?: Published
    Last Modified: 19 Oct 2018 00:21
    Identification Number:
    URI: http://eprints.lancs.ac.uk/id/eprint/67997

    Actions (login required)

    View Item