During this time, there is a slowdown in both the rates of respiration and heartbeat. Stage 1 sleep is a transitional phase that occurs between wakefulness and sleep, the period during which we drift off to sleep. The first stage of NREM sleep is known as stage 1 sleep. (credit “sleeping”: modification of work by Ryan Vaarsi) NREM Stages of Sleep 7 Brainwave activity changes dramatically across the different stages of sleep. In this section, we will discuss each of these stages of sleep and their associated patterns of brain wave activity.įigure 6. The first three stages of sleep are NREM sleep, while the fourth and final stage of sleep is REM sleep. In contrast, non-REM (NREM) sleep is subdivided into four stages distinguished from each other and from wakefulness by characteristic patterns of brain waves.

Brain waves during REM sleep appear very similar to brain waves during wakefulness. Rapid eye movement (REM)sleep is characterized by darting movements of the eyes under closed eyelids. Sleep can be divided into two different general phases: REM sleep and non-REM (NREM) sleep. These changes in brain wave activity can be visualized using EEG and are distinguished from one another by both the frequency and amplitude of brain waves (Figure 6.7). Instead, sleep is composed of several different stages that can be differentiated from one another by the patterns of brain wave activity that occur during each stage. Understand the role that REM and non-REM sleep play in learning and memory.Describe the differences between the three stages of non-REM sleep.Differentiate between REM and non-REM sleep.By the end of this section, you will be able to:

Introduction to deep sleep stage