Title

A Synaptic Basis for Auditory-Vocal Integration in the Songbird

Authors

Eric E. Bauer, Hiram CollegeFollow
Melissa J. Coleman, Claremont McKenna College; Pitzer College; Scripps CollegeFollow
Todd F. Roberts, University of North Carolina
Arani Roy, Duke University
Jonathan F. Prather, University of WyomingFollow
Richard Mooney, Duke UniversityFollow

Document Type

Article

Department

WM Keck Science

Publication Date

2-6-2008

Abstract

Songbirds learn to sing by memorizing a tutor song that they then vocally mimic using auditory feedback. This developmental sequence suggests that brain areas that encode auditory memories communicate with brain areas for learned vocal control. In the songbird, the secondary auditory telencephalic region caudal mesopallium (CM) contains neurons that encode aspects of auditory experience. We investigated whether CM is an important source of auditory input to two sensorimotor structures implicated in singing, the telencephalic song nucleus interface (NIf) and HVC. We used reversible inactivation methods to show that activity in CM is necessary for much of the auditory-evoked activity that can be detected in NIf and HVC of anesthetized adult male zebra finches. Furthermore, extracellular and intracellular recordings along with spike-triggered averaging methods indicate that auditory selectivity for the bird’s own song is enhanced between CM and NIf. We used lentiviral-mediated tracing methods to confirm that CM neurons directly innervate NIf. To our surprise, these tracing studies also revealed a direct projection from CM to HVC. We combined irreversible lesions of NIf with reversible inactivation of CM to establish that CM supplies a direct source of auditory drive to HVC. Finally, using chronic recording methods, we found that CM neurons are active in response to song playback and during singing, indicating their potential importance to song perception and processing of auditory feedback. These results establish the functional synaptic linkage between sites of auditory and vocal learning and may identify an important substrate for learned vocal communication.

Comments

First published in the Journal of Neuroscience, vol. 28, no. 6 (2008), by the Society for Neuroscience.

Data supplements requires login at journal. waiting for data permissions from publisher.

Previously linked to as: http://ccdl.libraries.claremont.edu/u?/irw,470.

Publisher pdf, posted with permission.

Recommended Citation

Bauer, Eric E., Melissa J. Coleman, Todd F. Roberts, Arani Roy, Jonathan F. Prather, and Richard Mooney. "A Synaptic Basis for Auditory-Vocal Integration in the Songbird." The Journal of Neuroscience 28.6 (2008): 1509-1522. DOI :10.1523/JNEUROSCI.3838-07.2008