AP PSYCHOLOGY

Detailed explanation-1: -Stage 3 and stage 4 of sleep are often referred to as deep sleep or slow-wave sleep because these stages are characterized by low frequency (up to 4 Hz), high amplitude delta waves (figuer below). During this time, an individual’s heart rate and respiration slow dramatically.

Detailed explanation-2: -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-3: -Stage 3 sleep is also known as N3 or deep sleep, and it is harder to wake someone up if they are in this phase. Muscle tone, pulse, and breathing rate decrease in N3 sleep as the body relaxes even further. The brain activity during this period has an identifiable pattern of what are known as delta waves.

Detailed explanation-4: -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-5: -In stages 3 and 4, deep sleep begins. Your eyes and muscles don’t move, and your brain waves slow down even further. Deep sleep is restorative. Your body replenishes its energy and repairs cells, tissues, and muscles.