My broad, long-term objective is to establish myself as an independent investigator of human audiovocal integration. Through this NINDS K22 Career Transition Award I will gain expertise in functional magnetic resonance imaging (fMRI) techniques and test hypotheses regarding the integration of sound in the central control of voice. Dr. Christy Ludlow of the Laryngeal and Speech Section of NINDS will act as primary mentor on this Award. Much of what is known about central voice motor control has come from research in non-human primates during production of genetically determined vocalizations. Very little is known about how vocalization is centrally controlled in humans, for whom productions are primarily learned. Auditory feedback plays a uniquely prominent role in learning and maintenance of human voice control. Although extensive studies of bat echolocation suggest midbrain networks as a potential system for automatic audiovocal error correction in humans, anatomical and physiological differences limit extrapolation of these findings across species.
Research Aim 1 is to identify the central regions associated with simple voluntary vocal behaviors under normal auditory feedback. It is hypothesized that central systems of voice fundamental frequency and amplitude control will vary with different vocal tasks. The normative findings obtained with Aim 1 will serve as basis for comparison with the data to be obtained during studies of the central generation of acoustically triggered vocal behaviors. Specifically, Aim 2 is to identify the central systems of activity associated with reflex-like audiovocal behaviors. It is hypothesized that reflex-like vocal responses are primarily associated with sub-cortical activity. The results of Aim 2 will provide a much-needed link between human and animal models of voice motor control, and will form a basis on which to examine more complex processes of voice motor control. Collectively, these outcomes will provide important information about the central control of voice in humans, contribute to models of normal voice motor control and result in a new understanding of human audiovocal integration. ? ?
| Burnett, Theresa A; McCurdy, Katie E; Bright, Jessica C (2008) Reflexive and volitional voice fundamental frequency responses to an anticipated feedback pitch error. Exp Brain Res 191:341-51 |
