The Relationship Between Sleep Length and Grade-Point Average Among College Students

Previous research indicated that short sleepers (those who typically sleep 6 or fewer hours out of every 24) report more symptoms of psychological maladjustment than do long sleepers (those who sleep more than 9 hours). The presence of psychological maladjustment symptoms have been found to negatively affect academic performance. Hence, it was hypothesized that short sleepers would report lower grade-point averages than those classified as long sleepers. A college student sample's self-reported typical sleep length and grade-point averages were explored. It was found that short sleepers reported significantly lower overall grade-point averages than did long sleepers. Directions for future research are offered. Sleep has been studied extensively (Hicks, Guista, Schretlen, 8,: Pellegrini, 1980; Kumar 8,: Viadya, 1984; Stuss 8,: Broughton, 1978). Most sleep research has examined sleep disorders, physiological variables associated with sleep, and sleep cycles (cf., Steriade 8,: McCarley, 1990). One area of sleep research which has received relatively little attention involves the identification of characteristics and behaviors correlated with sleep length. Sleep length research has identified three distinct classifications of sleepers. These include (1) short sleepers, individuals who when left to set their own schedule, sleep 6 or fewer hours, (2) average sleepers, individuals who sleep 7 to 8 hours, and (3) long sleepers, individuals who sleep 9 or more hours out of every 24 (Webb Webb, 1982). Consequently, studies have attempted to ascertain differences in individuals among these three sleep classifications aside from sleep time. Earlier research indicated that short sleepers were more likely to be ambitious, energetic, and psychologically healthy. Long sleepers we're described as nervous, self-critical, worriers, and often depressed (Hartmann, 1973). Conversely, more recent findings indicated that short sleepers, as compared to long sleepers, were more psychologically maladjusted, anxious, less creative, more neurotic, and more prone to hallucinate (Hicks, et al., 1980; Kumar Kumar Soper, Kelly, Hill & Wigfield, 1984). The experience of anxiety, psychological maladjustment, and neuroticism tend to adversely affect the educational experience by decreasing individuals' attention and concentration and increasing task performance errors (Woolfolk, 1993). It might be expected then, that individuals reporting the previously mentioned characteristics associated with short sleepers would also report lower academic performance as compared to long sleepers. Thus, it was hypothesized that individuals identifying themselves as short-sleepers would report significantly lower overall grade-point averages than long sleepers. Method Participants and Procedure Participants included 148 undergraduate students enrolled in introductory psychology classes. Participation was voluntary. The mean age for the sample was 19.86 years (sd = 3.85). Ages ranged from 18 to 42. Males composed 49% (72) of the sample and females 51% (75). Totals do not always equal 148 because data were missing. Using the method reported by previous studies (cf., Soper, et al., 1997), short sleepers were defined as those who reported sleeping an average of 6 or fewer hours per night. Average sleepers endorsed sleeping 7-8 hours per night. Long sleepers reported sleeping 9 or more hours per night. Instrumentation A consent form, demographic data sheet, and a questionnaire asking participants to indicate their average sleep length for a 24 hour period were administered. …