Date Thesis Awarded


Access Type

Honors Thesis -- Access Restricted On-Campus Only

Degree Name

Bachelors of Science (BS)




Robert C. Barnet

Committee Members

Joshua A. Burk

Deborah C. Bebout


This study utilized a rodent model of anxiety in which the defensive behavior of rats provides a measure of operational anxiety known as "Light-Enhanced Startle" (LES; Walker & Davis, 1997). The focus of the study was to explore age-dependent and sex-dependent vulnerabilities to the anxiety-producing effects of nicotine in rats. An additional goal was to establish the LES paradigm for use in adolescent animals. The effect of acute first-time exposure to nicotine on the magnitude of light-enhanced startle in adolescent versus adult rats was measured. Adolescent and adult animals did not have similar dose-response patterns revealing age-dependent differences in nicotine's effect on anxiety. Additionally, these different dose-response patterns depended on sex. In general, nicotine was anxiogenic in most conditions and females showed stronger anxiogenic responses to nicotine than males. Collectively, outcomes reveal age-dependent vulnerabilities to the anxiety-producing effects of nicotine that depend on drug dose and sex, and establish the light-enhanced startle paradigm for use as an animal model of anxiety expression in adolescence, which is viewed as a critical developmental period. Adolescence as a unique period of vulnerability to the effects of stress and advantages of the LES paradigm as an experimental model of anxiety are also discussed.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Public Domain Dedication 1.0 License.


Thesis is part of Honors ETD pilot project, 2008-2013. Migrated from Dspace in 2016.

On-Campus Access Only