Anxiety disorders can impair cognition and emotional control, particularly in the face of novel situations, which is concerning due to the high prevalence of such diagnoses. Exposure to unpredictable chronic stress can provide a way to induce anxiety-like behaviors in rodents by disrupting the stress response systems, including the HPA axis and autonomic nervous system. Pharmacological treatments, including SNRIs like venlafaxine, and voluntary exercise are both anxiolytic treatments that can alleviate the impacts of chronic stress. Using unpredictable chronic stress to mimic the human condition, and exposure to venlafaxine and exercise to mitigate the stress, the open field and elevated plus maze were used to assess anxious-like behaviors in Sprague-Dawley rats. It was hypothesized that chronic stress administration would induce anxious-like behaviors in the rodents and that implementing venlafaxine, exercise, or both would decrease anxiety behaviors. Chronic stress did cause an increase in anxious behaviors measured by the open field and elevated plus maze, supporting the effectiveness of unpredictable chronic stress as an anxiogenic. However, neither pharmacological nor non-pharmacological treatments decreased anxious-like behaviors when administered independently or in combination. Although the effects of treatment type were not found to be significant, it is important to consider various treatment options to best help anxiety symptoms in individuals, as anxiety is pervasive, can be debilitating, and more effective treatments are needed to help.


Stavnezer, Amy Jo




Animal Studies | Applied Behavior Analysis | Behavioral Neurobiology | Experimental Analysis of Behavior | Neuroscience and Neurobiology | Other Neuroscience and Neurobiology | Other Psychology


Anxiety, Unpredictable Chronic Mild Stress, Voluntary Exercise, SNRI, Pharmacological Agent, Stress-Response, Animal Studies, Restraint Stress

Publication Date


Degree Granted

Bachelor of Arts

Document Type

Senior Independent Study Thesis Exemplar



© Copyright 2022 Marly McGowan