By Dylan Crann

Faculty Mentor: Dr. Parrish Waters

Abstract

Humans who experience social isolation are at risk of developing depression
disorders, such as Major Depression Disorder. This disorder can be typified by stress and forgetfulness. This study combines behavioral and physiological approaches to understand the effects of social isolation in a model organism, being mice. Socially isolated mice exhibit many behaviors that are similar to these human behaviors and are commonly used as models for human depression. To simulate the effects of social isolation, we housed social and isolated groups of mice in respective cages. Following social and isolation simulation, memory tests such as the Barnes maze and the novel object recognition were conducted to provide measures of separate modes of memory that are associated with human depression.

Additionally, we used commercially available ELISA kits to analyze two
physiological systems that influence depression in humans: the glucocorticoid
corticosterone and the neurotrophin brain-derived neurotrophic factor (BDNF). Plasma corticosterone and BDNF from the frontal cortex and hippocampus were collected, respectively. These ligands are disrupted in humans with depression disorder and are implicated in stress-related behavioral changes in mice. This study is impactful because as social isolation becomes more common in our society, it is more pressing to understand how it may influence our behavior and physiology and can lead to pathological states.