UC Riverside Undergraduate Research Journal

Major Depressive Disorder (MDD) is characterized by the persistent presence of at least fivedepressive symptoms over a two-week period. These symptoms must include either depressedmood, or loss of interest or pleasure. Early identification, and ultimately treatment, of depressionmay be accomplished by identifying neural markers of individuals at risk for MDD, including thosewith subclinical depressive symptoms. Neuroimaging studies have shown that MDD is associatedwith impairments to integrity in white matter tracts such as the corpus callosum and internal capsule.However, it is unclear whether these same structures also are disrupted in subclinical depression. Thepresent study sought to examine this question through utilizing diffusion tensor imaging to assesswhite matter integrity as a function of Geriatric Depression Scale Short Form (GDS-SF) scores.Using a median split of GDS-SF scores, statistical analyses revealed no difference in white matterintegrity between low risk and high risk depression groups. However, there was a nonsignificant trend(p=0.072) such that higher GDS-SF scores were associated with decreased white matter integritylocalized to the corpus callosum, right internal capsule, left cingulum, external capsule and fornix.This finding extends previous research on MDD by providing evidence for similar neural correlatesof subclinical depression. This may provide insight into the development of MDD and ultimately aiddiagnostic and treatment efforts with early identification and intervention.