Contrast NREM and REM sleep. Why is there a "paradox" in REM sleep? Discuss dreams in REM vs. NREM sleep.

Question

What will be an ideal response?

Answer 1

Several times a night, when sleepers have cycled back to a shallower state of sleep, something curious happens. Their heart rate increases and becomes irregular, their blood pressure rises, and their breathing rate increases. Most characteristic of this period is the back-and-forth movement of their eyes, as if they were watching an action-filled movie. This period of sleep is called rapid eye movement, or REM sleep, and it contrasts with stages 1 through 3, which are collectively labeled non-REM (or NREM) sleep. REM sleep occupies a little more than 20 percent of adults' total sleeping time. Paradoxically, while heart rate, blood pressure, and breathing increase during REM sleep, the major muscles of the body appear to be paralyzed. In addition, and most important, REM sleep is usually accompanied by dreams, which whether or not people remember them-are experienced by everyone during some part of their night's sleep. Although some dreaming occurs in non-REM stages of sleep, dreams are most likely to occur in the REM period, where they are the most vivid and easily remembered.