Date of Award


Document Type


Degree Name

Master of Science


College of Arts and Sciences


Biology, MS

First Advisor

Pamela S. Coburn-Litvak


Problem. Humans may face psychological stressors in their everyday life due to their ability to contemplate future events. While long-term stress exposure may be detrimental to health, this study examines the possibility that exposure to unpredictable/controllable, moderate stress may cause resilience against future stressors. This is referred to as the "stress inoculation hypothesis." The effects of unpredictable/controllable stress can be illustrated as a rightward shift in an inverted U-shaped curve, where optimal performance (the top of the curve) can be maintained at higher stress levels. -- Method. Thirty-three male Sprague-Dawley rats were tested on the elevated-plus maze (EPM) for trait anxiety. Rats were then placed in housing platforms; 15 rats were exposed to unpredictable/controllable stress (UST) in the housing platform, and 18 rats were used as a control group (CT). After 21 days in the UST or CT housing, spatial memory and anxiety-related behaviors were tested under aversive conditions on the Barnes maze. -- Results. Spatial memory: UST rats took less time to reach the goal box on the Barnes maze (p0.05). -- Conclusion. These data are consistent with the "stress inoculation hypothesis." As humans, exposure to stress is unavoidable and unpredictable. The results of this study, however, indicate that stress does not always lead to negative consequences, but can be helpful. By causing a rightward shift in the inverted U-shaped curve, stress can better prepare us to face stressful situations in the future and reduce our anxiety about facing those stressors.

Subject Area

Rats--Effect of stress on., Stress (Psychology)

Creative Commons License

Creative Commons Attribution-No Derivative Works 4.0 International License
This work is licensed under a Creative Commons Attribution-No Derivative Works 4.0 International License.