AP PSYCHOLOGY

Detailed explanation-1: -In the deepest level of sleep, stage IV sleep, the predominant EEG activity consists of low frequency (1–4 Hz), high-amplitude fluctuations called delta waves, the characteristic slow waves for which this phase of sleep is named.

Detailed explanation-2: -Deep, slow brain waves known as delta waves begin to emerge during NREM stage 3 sleep-a stage that is also referred to as delta sleep. This is a period of deep sleep where any noises or activity in the environment may fail to wake the sleeping person.

Detailed explanation-3: -Deep sleep, also called slow-wave sleep. View Source, occurs in the third stage of non-rapid eye movement (NREM) sleep. During deep sleep, electrical activity in the brain appears in long, slow waves called delta waves.

Detailed explanation-4: -SWS, or delta sleep, follows stage 2 sleep and is characterized by polymorphic, semirhythmic delta waves accounting for at least 20% of the EEG activity. SWS is characterized by relative body immobility. SWS is maximal in young children and markedly decreases with age.

Detailed explanation-5: -Stage 4-REM Sleep The first round of REM in a night lasts about 10 minutes, with the stage getting longer and longer each time you enter REM in one night1. It’s also the deepest stage of sleep, where you’ll experience1: Quickened breathing. Faster heart rate and blood pressure.