TOW #22 - Article: "Turn Out the Light! It May Be Making You Moody" by Alexandra Sifferlin

Alexandra Sifferlin, a writer for TIME Healthland, wrote the article: “Turn Out the Light!” under the topic of depression and health. The exigence was to inform a random audience of the consequences of excessive light exposure so others can live healthier lives. This article described an experiment with rats that were exposed to light for longer periods of time. Researchers found that the rats exposed to more light had depression-like symptoms hence the same would apply to humans. Humans have cells in the eye activating the brain's limbic system when exposed to light. The system is responsible for memory and emotion and is functioned to slow down at night and speed up in the morning. Sifferlin provided solutions to this problem by providing tips on limiting light which were given by Samar Hattar, a biology professor at John Hopkins University. Hattar worked with his team to study light exposure problems which allowed this article to appeal to ethos because credible sources were provided to support Sifferlin’s claim which was to make others limit excessive light exposure. 
The article also consisted of jargon, but only to refer to medical concepts such as “limbic system,” “intrinsically photosensitive retinal ganglion cells,” and “cortisol.” The use of such rhetorical devices allowed Sifferlin to accomplish her purpose which was to encourage readers to limit using light at night. She did this by describing the rat experiment in a way that was very easy to understand with jargon that was clearly explained and defined.