We have all heard the effect of sleep deprivation on cognitive function and studying, memorization, attention span, and vigilance. These are elements of our school life that are known to be affected by pulling “all - nighters” the day before an algebra test. But what is actually happening, and why are teachers and mammies always harping on about sleep! I hope to clarify the facts, using the summary empirical evidence below.
In one study, young adults were restricted to 4, 6, or 8 hours of time in bed per night for 14 days, under controlled laboratory conditions. Several times per day, subjects performed a psycho-motor vigilance test (PVT) of attention, a digit-symbol substitution task (DSST) test of working memory, and a serial addition/subtraction test (SAST) of cognitive throughput.
The performance of subjects restricted to 4 and 6 hours in bed per night worsened progressively over the 14 days on all cognitive tasks. After 14 days, their cognitive performance was similar to that of subjects who are totally sleep deprived for 24 to 48 hours. Similar findings of progressive worsening of performance on the PVT were reported in a second study in which time in bed was restricted to 3, 5, or 7 hours, over a shorter, 7 day period. Even at 7 hours sleep, our cognitive functions are affected!
Cognitive deficits in the setting of sleep deprivation have also been demonstrated in real-life circumstances demanding high level functioning. One such example is a series of studies performed on medical interns while “on the job”. In one of these studies, interns worked either a traditional schedule of 85 hours per week, or a modified schedule averaging 65 hours of work per week, which resulted in an additional 6 hours of sleep per week. Interns working the traditional schedule had more than twice the rate of attention failures during work, as measured by the intrusion of slow rolling eye movements into wakefulness. Another study found that medical interns working in the intensive care unit on a traditional schedule consisting of extended shifts of greater than 24 hours made 36 percent more serious medical errors than interns on a modified schedule with shorter shifts and less total hours per week. You can imagine that similar effects would be apparent among Junior and Leaving Certificate students.
In summary, sleep deprivation results in dynamic changes in patterns of brain activation. These changes may result in either increased or depressed activity in brain regions typically required for a given task. In other instances, attempts to compensate for the negative effects of lack of sleep on cognition appear to recruit entirely new regions of the brain. So, get a regular sleep pattern in through routine!
You can find the full report through the link below: