Undergraduate Honors Theses

Thesis Defended

Spring 2015

Document Type

Thesis

Type of Thesis

Departmental Honors

Department

Psychology & Neuroscience

First Advisor

Dr. Daniel Barth

Second Advisor

Dr. Joanna Arch

Third Advisor

Dr. Andrea Feldman

Abstract

Traumatic brain injury (TBI) impacts over one million people in the United States every year and significantly increases an individual’s risk of developing a psychiatric disorder. Previous research in our lab has highlighted the role of neuroinflammation in TBI and the development of post-injury anxiety in rodent models. The objective of this study is to characterize the brain regions involved in the anxiety-like behaviors observed in previous studies and in an immediate shock paradigm. The rats were randomly assigned to one of six groups: LFPI+shock, LFPI+no shock, naïve+shock, naïve+no shock, sham-operated, and LFPI+MN166. Lateral fluid percussion injury (LFPI) was used to model TBI in the rodents and shock refers to animals that were shocked in the immediate shock paradigm. The expression of c-fos was measured and compared between groups across multiple brain regions including the hippocampus, insula, amygdala, paraventricular nucleus, central gray, bed nucleus of the stria terminalis, and regions of the prefrontal cortex. The LFPI+shock rats displayed significantly higher freezing behavior in the immediate shock paradigm than all other treatment groups. The results of the c-fos expression measurements partially support previous findings on brain regions involved in anxiety, but are not consistent with the expected pattern of activation based on the behavioral results of the immediate shock paradigm.