Audio-vocal monitoring system revealed by mu-rhythm activity
- 1Department of Computer Science and Engineering, Toyohashi University of Technology, Toyohashi, Japan
- 2Department of Developmental Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
- 3Industrial Cooperation Team, Nishina Center for Accelerator-Based Science, RIKEN, Wako, Japan
- 4School of Information, Kochi University of Technology, Kami, Japan
Understanding the neural mechanisms underlying speech production has a number of potential practical applications. Speech production involves multiple feedback loops. An audio-vocal monitoring system plays an important role in speech production, based on auditory feedback about the speaker’s own voice. Here we investigated the mu-rhythm activity associated with speech production by examining event-related desynchronization and synchronization in conditions of delayed auditory feedback (DAF) and noise feedback (Lombard). In Experiment 1, we confirmed that the mu-rhythms were detectable for a conventional finger-tapping task, and vocalization. In Experiment 2, we examined the mu-rhythms for imagined speech production. We tested whether the same motor-related mu-rhythm activity was exhibited while participants listened to their own voice, and while reading. The mu-rhythms were observed for overt vocalization and covert reading, while listening to simulated auditory feedback of the participants’ own voice reading text. In addition, we found that the mu-rhythm associated with listening was boosted and attenuated under the DAF and Lombard conditions, respectively. This is consistent with the notion that auditory feedback is important for the audio-vocal monitoring system in speech production. This paradigm may help clarify the way in which auditory feedback supports motor planning, as indexed by the motor-related mu-rhythm.
Keywords: event-related desynchronization, speech production, motor imagery, delayed auditory feedback, Lombard effect
Citation: Tamura T, Gunji A, Takeichi H, Shigemasu H, Inagaki M, Kaga M and Kitazaki M (2012) Audio-vocal monitoring system revealed by mu-rhythm activity. Front. Psychology 3:225. doi: 10.3389/fpsyg.2012.00225
Received: 12 September 2011; Accepted: 18 June 2012;
Published online: 06 July 2012.
, Catholic University of Chile, Chile
Copyright: © 2012 Tamura, Gunji, Takeichi, Shigemasu, Inagaki, Kaga and Kitazaki. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and subject to any copyright notices concerning any third-party graphics etc.
*Correspondence: Atsuko Gunji, Department of Developmental Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Ogawa-Higashi 4-1-1, Kodaira, Tokyo 187-8553, Japan. e-mail: firstname.lastname@example.org