[...]... a lack of exercise and nutrition, however, lack of sleep leads to serious consequences much more rapidly The health consequences of lack of exercise take years to develop A person can go days without food In contrast, a day of sleep deprivation, or several days of inadequate sleep, can be deadly • • Sleep is homeostatically regulated, which means that if you do not get the requisite amount of sleep, ... active, and bizarre dreams Hence, REM sleep became known as dreaming sleep We now know that dreaming occurs in nonREM sleep as well, but it is of a different nature—less vivid, less dramatic, less emotional The extreme nature of dreams during REM sleep remains an important feature of this state of sleep Muscle Atonia in REM Sleep • There is another important feature of REM sleep that distinguishes it both... 19 The EEG of stage 3 nonREM sleep has most of its power in the slow frequencies, and the EEG of REM sleep has more of its power in faster frequencies If we compare the first bout of nonREM sleep with subsequent bouts of nonREM sleep, we find that there is a progressive decline in power in the slow frequencies This seems to indicate a process that reflects a high need at the beginning of sleep and a... complex mixture of sine waves Which sine waves would you expect to predominate in REM sleep and in deep nonREM sleep? 2 What change is seen in sleep after a prolonged period of wake? 23 Sleep across the Life Span Lecture 4 I n the first weeks of life, a newborn sleeps about 16 hours a day, and that sleep is about equally divided between REM and nonREM sleep The daily amount of nonREM sleep stays about... individual episodes of REM and nonREM sleep last? Does the expression of these states change across the night? How do the sleep states relate to the duration of prior wakefulness? Three Stages of NonREM Sleep • Let’s consider a sleep study that involves recording each subject’s EEG, EMG, and EOG activity during an all-night sleep session ○○ Preceding sleep, there is usually a time of relaxed wakefulness... discoveries of Kleitman, Aserinsky, and Dement led to the categorization of sleep into two states: REM (rapid eye movement) sleep and nonREM sleep Sometimes REM sleep is referred to as desynchronized sleep, or active sleep NonREM sleep, on the other hand, is sometimes referred to as synchronized sleep, slow-wave sleep, or quiet sleep • The Chicago group made another important discovery during their... onset of sleep ○○ That hypothesis led to experiments that strongly indicated that delta power is linked to some sleep restorative process Sleep Intensity • Our common experience is that we sleep more after an extended time of being awake A whole week of short sleep, maybe 5 or 6 hours per night, is usually followed by catch-up on the weekend— sleeping in But usually, for most of us, our payback sleep. .. about the actual function of nonREM sleep • The main change that is seen in REM sleep in response to sleep deprivation is increased time spent in REM sleep Thus, the sleep following an extended period of wakefulness is characterized by longer REM sleep bouts ○○ The increased time spent in REM following sleep deprivation can actually push off the nonREM recovery, and thus, total sleep recovery may take... generation of slow waves in the EEG? In a later lecture, we will explore this lead as a possible way of discovering a function of sleep • For our next lecture, however, we will describe the characteristics of sleep and ask how these aspects of sleep change across the life cycle from the newborn to the elderly Suggested Reading Borbely, Tobler, and Hanagasioglu, “Effect of Sleep Deprivation on Sleep and... also discuss sleepwalking, which occurs during nonREM sleep • Measuring all the various characteristics of sleep that we touched on in this lecture helps us to diagnose and study sleep disorders, which are many Also, investigations into the mechanisms underlying these characteristics of sleep lead to the discovery of clues that can give us deeper understanding of sleep mechanisms and sleep functions . consequences of personal sleep debt and America’s national sleep decit, the course identies the dening features of sleep and provides a clear blueprint of the “architecture” of sleep that. challenges of our day. The Personal Sleep Debt • In the absence of disease, there are three basic components of a healthy lifestyle: nutrition, physical tness, and sleep. In comparison to a lack of. lack of sleep leads to serious consequences much more rapidly. The health consequences of lack of exercise take years to develop. A person can go days without food. In contrast, a day of sleep