Effect of night shift work on sleep memory

Abstract

Sleep deprivation is a very common phenomenon world-wide and it has been known to affect motor and cognitive functions. In this multi-faceted study, we sought to assess the effect of sleep /deprivation on mood, cognitive performance, and memory, as well as any potential. Our sample was drawn from anesthesia residents at the Augusta University Medical Center. Our first focus was to determine the effects of sleep deprivation on mood, cognitive performance, and memory. Tasks were split amongst members of the research team, and I was charged with assessing memory retention and working memory via the Ospan test, a computerized test involving letter sequence memorization and mathematical problem solving. I administered the Ospan to residents at a baseline or control reading, then after their calls. If the residents had a night float (a stretch of calls over 5 days), then I would assess them after the first day of the float, right after the float, and 24 hours after the float. The higher the score on the Ospan, the better working memory and memory retention abilities were in that resident. Data collection began in April 2018 and continued into February 2019. For our secondary evaluation, we assessed how sleep deprivation affected gene expression, by looking at a set of genes known to be associated with sleep deprivation. These genes were: PER1, PER2, and ARNTL or BMAL. (Gene details explained in body paragraphs). Following similar protocol to the first study, expression was assessed before and after night calls and night floats. The testing involved sampling saliva from the residents who participated in the cognitive assessments in Part 1, isolating RNA from the samples, creating cDNA from the RNA, and then performing microarray analysis on the samples. To produce the cDNA samples from the RNA samples, reverse transcriptase PCR was used to create cDNA and amplify the number of copies of genes we had to work with. Microarray analysis was performed to measure the actual gene expressions of our genes of interest. These were certain genes which were previously found in another study by multiple Ravula 3 researchers at the University of Surrey, in the UK (article title given below later) to affect sleep deprivation. These genes were then examined to determine if those specific genes increased, decreased, or maintained their expression, post-sleep deprivation.