The purpose of this paper is to evaluate research on the effects of sleep deprivation. Many negative consequences of sleep deprivation have been identified in the research literature. a Dr. Breus enumerates some negative consequences of less sleep: poor performance and alertness, decreased memory and cognitive skills, strenuous relationships, poor quality of life, and increase in accidents and injuries. Less hours of sleep may cause a significant decrease in performance and alertness. According to Dr. Breus, there is a 32% decrease in alertness for every one and a half hours less sleep than normal. A reduction in performance and alertness will then cause impairment in your memory and cognitive ability. When you have fewer hours of sleep, your ability to think properly reduces. Sleep deprivation also causes relationships to become strenuous. Sleep disorders may cause moodiness which then leads to conflicts. Sleep deprivation causes drowsiness which is responsible for 100,000 automobile accidents, 71,000 injuries and 1550 fatalities, as the National Highway Traffic Safety Administration (NHTSA) estimated (Breus).
Dr. Aralem conducted a study recently to examine possible deleterious effects of sleep deprivation on the quiz scores of students in an introductory psychology course. Before evaluating this study, let me provide a brief summary of the study. a According to Dr. Harlem, students’ poor performance on their Monday quiz results from the students’ lack of sleep since Monday is preceded by weekend nights wherein students stay late at night. b The students’ results on their Monday and Wednesday quiz are the dependent measures of the study. This indicates the students’ academic performance. c The variable manipulated in the study is the students’ sleeping habits. Participant students were divided into groups depending on their sleep habits. d The study is not a true experiment since the participants to the study are not randomly chosen. The selection of the participants is voluntary. Moreover, the sample size is not large enough to represent an entire population. e The study concluded that poor academic performance results from insufficient sleep.
Dr. Aralem controlled for several extraneous variables in his study. a The controlled variables in the study are the number of hours the students get to sleep (in each of the four groups), the quizzes, and the participants’ knowledge of the purpose of the study. b In order to control the number of hours the students get to sleep, Dr. Aralem divided the students into four groups based on their sleeping habits. The quizzes are controlled since the same quiz is given to all the students. The students are not told of the purpose the study until the end of the experiment to avoid bias. In this way, the students answered to their quizzes without a regard to their scores.
Unfortunately, Dr. Aralem failed to control for several important variables, potentially jeopardizing his interpretation of the results. a The variables that should have been controlled are the students’ academic performance in their previous quizzes, the students’ study habits, and their family background. b Students who have seven or more hours sleep might be the students who always perform well in class and hence, they won’t have difficulty answering the quizzes. The students who have fewer hours of sleep might have poorer study habits than those with seven or more hours of sleep. Moreover, the students who have fewer hours to sleep might be experiencing problems and hence, they weren’t able to answer to quizzes since they are thinking of their problems.
My analysis reveals that Dr. Aralem’s study includes several important controls, but also has several flaws. a Hence, Dr. Aralem’s conclusion that insufficient sleep leads to poorer academic performance is not appropriate. He failed to control for several important variables and thus, the interpretation of results are put at risk. b In order to conduct a more valid experiment, Dr. Aralem should have specified all the important variables that need to be controlled. He should have chosen the students at random, instead of asking them to volunteer to guard against bias. It is good to divide the students into four groups based on their sleeping habits. However, Dr. Aralem should also consider their over-all academic performance, their study habits and their background.
Lathea is a Masters student interested in improving Dr. Aralem’s study by examining scores on a midterm exam in a graduate statistics class. She randomly picks twenty of her classmates and randomly assigns them to two groups, Group 1 and Group 2. She finds that the midterm average for Group 1 was 68, a D, whereas the average for Group 2 was 85, a B. Lathea then asked each student how many hours of sleep they got before the midterm exam. a The average amount of sleep for Group 1 is 6 hours while for Group 2, the average is 5 hours. This does not support Lathea’s hypothesis that sleep is a factor in Group 1’s poor performance on the exam since Group 1 has more hours of sleep than Group 2. b Students in Group 1 may have poorer study habits than those in Group 2, hence Group 1 did worse on the exam than Group 2. Also, midterm exam scores in Group 1 might be on the extremes. Meaning, some students may have really high scores while other may have really low scores. That is, the scores are not normally distributed. Hence, the average is worse than that of Group 2. c Lathea cannot conclude from her results that sleep deprivation is a cause of poor performance in midterm exam, since the average amount of sleeping hours of Group 1 is better than that of Group 2. Her study was not an improvement of Dr. Aralem’s study. She may have randomly chosen the participants in the study but she failed to control for all the other important variables in Dr. Aralem’s study such as the students’ sleeping habits. Moreover, she did not improve on what Dr. Aralem failed to control such as the students’ overall academic performance and their study habits.