The research of this laboratory focuses on neural mechanisms controlling the voice and the larynx.
For the past 15 years, we have been working on the development of a new, non-invasive technique for this study. We have found that when people hear their own voice through earphones, and when the voice pitch through the earphones is unexpectedly changed upwards or downwards, people automatically adjust the pitch of their voice. This adjustment represents a way the neural mechanisms controlling the voice respond to auditory feedback. This phenomenon also indicates that there is a close coupling between the auditory system's monitoring of voice and the motor system for adjusting the laryngeal system for voice output.
Thus, this new technique provides us with a way of exploring how auditory feedback is used to help control vocal output. There are several new lines of research that we are carrying out in order to learn about the neural mechanisms related to the audio-vocal system.
1. We are recording event-related potentials (ERPs) from EEG electrodes in an effort to learn how perturbations in voice auditory feedback affect these brain potentials.
2. We are doing electrocorticogrphy (ECoG), the recording of potentials directly from the brain surface in patients undergoing treatment for epilepsy.
3. We are conducting fMRI studies in people as they are receiving perturbations in their voice auditory feedback. These studies teach us about which brain areas are involved in this process.
4. We are using transcranial magnetic stimulation (TMS) techniques to identify how different cortical areas are involved in the audio-vocal reflexes. In brief, TMS pulses are applied to specific cortical areas at specific times during the reflex. The results tell us how these specific brain areas are involved in the reflex.
5. We are beginning studies of ERPs and fMRI in patients with schizophrenia. The goal of this research is to learn about neural mechanisms that may be involved in the vocal hallucinations that some patients report.
6. We are studying audio-vocal reflexes in patients with Parkinson’s disease. It is well known that these patients often speak with a voice that is too quiet. We are finding that these patients produce unusually large responses to perturbations in voice auditory feedback, which suggests sensory processing of voice auditory feedback may be abnormal in these patients.
Recent publications of our work on pitch and loudness-shifted voice feedback:
Burnett, T. A. , Senner, J.E. & Larson, C.R. Voice F0 responses to pitch-shifted auditory feedback: A preliminary study. J. Voice 11 (2), 202-211, 1997.
Theresa A Burnett, Marcia B. Freedland, Charles R. Larson, Timothy C. Hain. Voice F0 Responses to Manipulations in Pitch Feedback. J. Acoust. Soc. Am., 103, 3153-3161, 1998.
Larson, C.R. Cross-modality influences in speech motor control: The use of pitch shifting for the study of F0 control. Journal of Communication Disorders. 31, 489-503, 1998.
Hain, T C, Burnett, T A., Kiran, S. , Larson, C. R., Singh, S. and Kenney, M.K. Instructing Subjects to Make a Voluntary Response Reveals the Presence of Two Components to the Audio – Vocal Reflex, (Experimental Brain Research, 130, 133-141, 2000).
Larson, C.R., Burnett, T.A., Kiran, S., Kenney, M.K., Hain, T.C.Effects of pitch-shift velocity on voice F0 responses. J. Acoust. Soc. Am., 101 (1), 559-564, 2000.
Lazarus, C.L., Logemann, J.A., Pauloski, B.R., Rademaker, A.W., Larson, C.R., Mittal, B.B. & Pierce, M. Swallowing and tongue function following treatment for oral and oropharyngeal cancer. J. Speech Lang. Hear. Res., 43, 1011-1023, 2000.
Kiran, S. & Larson, C.R. Effect of duration of pitch-shifted feedback on vocal responses in Parkinson’s Disease patients and normal controls. (Journal of Speech/Language hearing Research, 44, 2001).
Hain, T.C., Burnett, T.A., Larson, C.R., and Kiran, S. T.C. Effects of delayed auditory feedback (DAF) on the pitch-shift reflex J. Acoust. Soc. Am., 109 (5), 2146-2152, 2001.
Larson, C.R., Burnett, T.A., Bauer, J.J., Kiran, S. & Hain T.C. Comparison of voice F0 responses to pitch-shift onset and offset conditions. J. Acoust. Soc. Am., 110 (6), 2845-2848, 2001.
Burnett, T.A. & Larson, C.R. Early pitch-shift response is active in both steady and dynamic voice pitch control. J. Acoust. Soc. Am. 112 (3), 1058-1063, 2002.
Bauer, Jay J. and Larson, C.R. Audio-vocal responses to repetitive pitch-shift stimulation during a sustained vocalization: Improvements in methodology for the pitch-shifting technique. J. Acoust. Soc. Am. 114 (2), 1048-1054, 2003.
Leydon, Ciara, Bauer, Jay J. & Larson, Charles R. The role of auditory feedback in sustaining vocal vibrato. J. Acoust. Soc. Am. 114 (3), 1575-1581, 2003.
Xu, Yi, Larson, Charles , Bauer, Jay, Hain, Timothy. Compensation for pitch-shifted auditory feedback during the production of Mandarin tone sequences. J. Acoust. Soc. Am. 116 (2), 1168-1178, 2004.
Sivasankar, M., Bauer, J.J., Babu, T, Larson, C.R. Voice responses to changes in pitch of voice or tone auditory feedback. J. Acoust. Soc. Am., 117 (2), 850-857, 2005.
Bauer, J.J., Mittal, J., Larson, C.R. Hain, T.C. Vocal responses to unanticipated perturbations in voice loudness feedback: An automatic mechanism for stabilizing voice amplitude. J. Acoust. Soc. Am. 119 (4), 2363-2371, 2006.
Chen, S.H., Liu, H., Xu, Y., Larson, C.R. Voice F0 Responses to Pitch-Shifted Voice Feedback During English Speech. J. Acoust. Soc. Am. 121 (2), 1157-1163, 2007.
Larson, C. R., Sun, J. and Hain, T. C. Effects of simultaneous perturbation of voice pitch and loudness feedback on voice F0 and amplitude control. J. Acoust. Soc. Am. 121 (5), 2862-2872, 2007.
Liu, H., Zhang, Q., Xu, Y. and Larson, C.R. Compensatory responses to loudness-shifted voice feedback during production of Mandarin speech. J. Acoust. Soc. Am. 122 (4), 2405-2412, 2007.
Liu, H. and Larson, C.R. Effects of perturbation magnitude and voice F0 level on the pitch-shift reflex. J. Acoust. Soc. Am. (In Press).
Liu, H. and Larson, C.R. Effects of perturbation magnitude and voice F0 level on the pitch-shift reflex. J. Acoust. Soc. Am. 122 (6), 3671 – 3677, 2007.
Russo, N. M., Larson, C., Kraus, N. Audio-Vocal System Regulation in Children with Autism Spectrum Disorders, Exp. Brain Res, 188, 111-2124, 2008.
Larson, C.R., Altman, K.W., Liu, H., Hain. T.C. Interactions between auditory and somatosensory feedback for voice F0 control, Exp. Brain Res, 187, 613-621, 2008.
Liu, H., Xu, Y., Larson, C.R. Suppression of vocal responses to pitch perturbations during Mandarin speech, J. Acoust. Soc. Am., 125, 2299-2306, 2009.
Behroozmand, R., Karvelis, L., Liu, H. and Larson, C. R. <a href="https://wamprod1.itcs.northwestern.edu:443/amserver/cdcservlet?goto=https%3A%2F%2Fsesame.library.northwestern.edu%3A443%2Fcgi-bin%2FssoEzpCheck.pl%3Furl%3Dhttp%3A%2F%2Fwww.sciencedirect.com%2Fscience%3F_ob%3DArticleURL%26_udi%3DB6VNP-4WGT66F-2%26_user%3D965532%26_coverDate%3D07%252F31%252F2009%26_alid%3D1143110426%26_rdoc%3D1%26_fmt%3Dhigh%26_orig%3Dsearch%26_cdi%3D6184%26_sort%3Dr%26_docanchor%3D%26view%3Dc%26_ct%3D1%26_acct%3DC000049540%26_version%3D1%26_urlVersion%3D0%26_userid%3D965532%26md5%3De413c1ac0e6a489513ccc7e22ee7cf44&RequestID=614201702&MajorVersion=1&MinorVersion=0&ProviderID=http%3A%2F%2Fsesame.library.northwestern.edu%3A80%2Famagent&IssueInstant=2010-07-13T09%3A38%3A56Z" rel="nofollow">Vocalization-induced enhancement of the auditory cortex responsiveness during voice F0 feedback perturbation</a>. Clinical Neurophysiology, Volume 120, Issue 7, July 2009, Pages 1303-1312.
Liu, H., Auger, J. and Larson, C.R. Voice fundamental frequency modulates vocal response to pitch perturbations during English speech. , J. Acoust. Soc. Am. EL, 127 (1), 2010
Liu, H., Russo, N.M. and Larson, C.R. Age-related differences in vocal responses to pitch feedback perturbations: A preliminary study. J. Acoust. Soc. Am., 127 (2), 1042-1046
Liu, H., Behroozmand, R., Larson, C.R. Enhanced neural responses to self-triggered voice pitch feedback perturbations. NeuroReport, 21 (7), 527 – 531, 2010.
Behroozmand, R., Liu, H., Larson, C.R. Time-dependent neural processing of auditory feedback during voice pitch error detection. J. Cog. Neurosci. (In Press).