4Epworth Sleepiness Scale How likely are you to doze off or fall asleep in the following situations, in contrast to feeling just tired? This refers to your usual way of life in recent times. Even if you have not done some of these things recently try to work out how they would have affected you.Use the following scale to choose the most appropriate number for each situation: 0 = no chance of dozing = slight chance of dozing = moderate chance of dozing 3 = high chance of dozing Sitting and readingWatching TVSitting inactive in a public place (e.g. a theater or a meeting)As a passenger in a car for an hour without a breakLying down to rest in the afternoon when circumstances permitSitting and talking to someoneSitting quietly after a lunch without alcoholIn a car, while stopped for a few minutes in traffic
10Why is sleep necessary? Repair and restoration theory NREM sleep: physiological functionsREM sleep: mental functionsEvolutionary or adaptive theoryConservation of energySleep as a hazardous activityInformation consolidation theoryProcessing informationBuilding long-term memoryRepair/restoration: revitalizing and restoring the physiological processes that keep the body and mind healthy and properly functioning. NREM sleep is important for restoring physiological functions, while REM sleep is essential in restoring mental functions. Periods of REM sleep increase following periods of sleep deprivation and physical activity. During sleep, the body also increases its rate of cell division and protein synthesis, further suggesting that repair and restoration occurs during sleeping periods.Evolutionary: periods of activity and inactivity evolved to conserve energy. All species have adapted to sleep during periods of time when wakefulness would be the most hazardous. Research of different animal species: animals with few natural predators, such as bears and lions, often sleep between 12 to 15 hours each day; animals with many natural predators have only short periods of sleep, usually getting no more than 4 or 5 hours of sleep each day.Info consolidation: people sleep to process information acquired during the day and prepare for the day to come, cement things we have learned during the day into long-term memory; sleep deprivation studies show that lack of sleep has a serious impact on the ability to recall and remember information.
11How much sleep do we need? “Mortality associated with sleep duration and insomnia”In 1982, the Cancer Prevention Study II of the American Cancer Society asked participants about their sleep duration and frequency of insomnia. Cox proportional hazards survival models were computed to determine whether sleep duration was associated with excess mortality up to 1988, controlling simultaneously for demographics, habits, health factors, and use of various medications.Participants were >1.1 million men and women from 30 to 102 years. The best survival was found among those who slept 7 hours per night.Participants who reported sleeping 8 hours or more experienced significantly increased mortality hazard, as did those who slept 6 hours or less.Shown are the hazard ratios from the 32-covariate Cox models and the percentage of men and women reporting each sleep duration. The reference duration of 7 hours is represented by the lighter bars.Kripke et al. Archives of General Psychiatry, 2002
12Sleep needs change with age Adults7-8 hoursTeens9-10 hoursChildren10-11 hoursToddlers hoursNeonates hours