Complex Acoustical Feature Representation in the Zebra Finch Caudomedial Neostriatum (Ncm)

Zebra finches use an array of complex vocal patterns (songs) to mediate individual as well as species recognition. Although behaviorally obvious, it is unclear how these discrete auditory perceptual objects are represented in the brain and linked to appropriate behavioral responses. In the caudomedial neostriatum (NCM) of the zebra finches, the stimulus selective and contextual (novel vs. familiar) nature of zenk activation as well as results from electrophysiological studies suggest an involvement of this auditory region in complex auditory processes. In this thesis, we present a primary analysis of the representational strategies available in the neurophysiological responses of neurons in the NCM. We developed a pair of matched auditory stimuli that share the same acoustic envelope (acoustic contour), but differ in their spectral organization (acoustic texture). We confirmed that these two stimuli are discriminated using specific genomic habituation as an assay. We then recorded from simultaneous responses from multiple single units in NCM to observe how the response patterns varied with acoustic texture and prolonged exposure. The results reveal that NCM neurons dynamically integrate both spectral and envelope information, and a stable representation of a particular song emerges in the broad cell population regardless of zenk expression pattern. On the other hand, decrease in the mean firing rate of the cell population was correlated with the zenk habituating events. These findings suggest that contextual associations may be made not by changing the fine structure of the response within NCM, but via transient increases in mean firing rate and gene activity.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Molecular and Integrative Physiology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Park, Kevin Hong Joon

Contributors dc:contributor

• Clayton, David F.

• Biology, Animal Physiology

Language dc:language

eng

Identifier

(MiAaPQ)AAI3070409

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/87222