Light pollution is a major issue, contributing to disruptions in human circadian rhythms, including sleep cycle, metabolism, and hormone synthesis and release. This pollution comes from streetlights and sporting stadiums, as well as other contributors such as smart phones, tablets and computers. These smart devices emit blue light, which has been found to have more detrimental effects on circadian rhythms than white light. Light at night has been associated with decreased learning and memory and an increase in cortisol, the stress hormone. The aim of this study was to examine the effect of blue light at night on rodent learning and memory in the water radial arm maze. Trilostane, used to block corticosterone synthesis, was administered daily to male SAS rats in 8mg/kg doses. Subjects were split into four groups, half in light at night and half in a normal 12-hour light dark cycle, and half of each group received trilostane. There appeared to be a trend reflective of learning across all groups for the twelve days in the WRAM. Additionally, there appears to be a difference in learning for the light condition groups, with the light at night condition appearing to learn more slowly than the light/dark condition. There was no significant difference in corticosterone levels for the drug conditions. However, it can be said that the presence of blue light at night does negatively impact learning and memory in the beginning stages of learning.


Stavnezer, Amy Jo




Animal Studies

Publication Date


Degree Granted

Bachelor of Arts

Document Type

Senior Independent Study Thesis



© Copyright 2016 Taylor J. Raybuck