What are significant features of REM sleep?

In REM sleep, a distinct brain wave pattern is observed that is characterized by sawtooth waves. These waves are typically irregular and resemble the shape of saw teeth, which is where the name comes from. This pattern of neural activity is associated with fast, desynchronized brain activity, which is similar to that seen in wakefulness, reflecting the heightened brain activity that occurs during this sleep stage.

REM sleep is also the stage where dreaming predominantly occurs, and this is closely related to the unique waveforms seen in this stage. The presence of sawtooth waves indicates a readiness of the brain to engage in the types of cognitive processing that are typical during dream states.

While other types of brain waves, like delta, spindles, and theta waves, play important roles in different sleep stages, they do not specifically characterize REM sleep. Delta waves are associated with deep sleep stages, sleep spindles occur during NREM phases, and theta waves are often seen in lighter stages of sleep and during relaxed wakefulness or light sleep. Observing sawtooth waves is crucial for identifying REM sleep as it differentiates this active phase from others in the sleep cycle.