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Which sleep stage is a transitional phase that occurs between wakefulness and sleep?

Stage 1 sleepStage 1 sleep is a transitional phase that occurs between wakefulness and sleep, the period during which we drift off to sleep. During this time, there is a slowdown in both the rates of respiration and heartbeat.

Which stage of sleep is a transition between wakefulness and sleep?

Stage 1 non-REM sleep

Stage 1 non-REM sleep marks the transition from wakefulness to sleep. This stage typically lasts less than 10 minutes and is marked by a slowing of your heartbeat, breathing, and eye movements , as well as the relaxation of your muscles.

What is stage 3 of sleep?

Stage 3 sleep is also known as 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.

What is Stage 4 of sleep?

Stage 4 is an even deeper sleep where the brain waves further slow and sleepers are very difficult to wake. It’s believed that tissue repair occurs during the stage of sleep and that hormones are also released to help with growth.

What is the alpha stage of sleep?

The early portion of stage 1 sleep produces alpha waves, which are relatively low frequency (8–13Hz), high amplitude patterns of electrical activity (waves) that become synchronized (Figure). This pattern of brain wave activity resembles that of someone who is very relaxed, yet awake.

What is Stage 2 of sleep?

Stage 2: You are in light sleep. Your heart rate slows and your body temperature drops. Your body is getting ready for deep sleep. This can last for 10-25 minutes. Stages 3: This is the deep sleep stage.

Are there 4 or 5 stages of sleep?

There are five stages of sleep during the sleep cycle.

Scientists categorized the stages of sleep based on the characteristics of the brain and body during sleep. Stage 1,2,3, and 4, are categorized as ‘non-REM sleep’, and the fifth stage, is REM sleep.

What are the 5 stages of sleep called?


  • Sleep is broken down into 5 phases: wake, N1, N2, N3, and R. …
  • The first stage is the wake stage or stage W, which further depends on whether the eyes are open or closed. …
  • This is the stage associated with dreaming.

What happens in Stage 1 of sleep?

The first stage of the sleep cycle is a transition period between wakefulness and sleep. If you awaken someone during this stage, they might report that they were not really asleep.

What are the 4 stages of NREM sleep?

NREM sleep is divided into stages 1, 2, 3, and 4, representing a continuum of relative depth. Each has unique characteristics including variations in brain wave patterns, eye movements, and muscle tone. Circadian rhythms, the daily rhythms in physiology and behavior, regulate the sleep-wake cycle.

What are the stages of sleep?

Sleep has been traditionally divided into 4 categories: awake, light, deep, and REM sleep. Each one plays an essential role in maintaining your mental and physical health. Note: As you’re reading about sleep, you may also see the terms “NREM” or “Stages 1-4.” These are simply other terms for the phases of sleep.

What stage of sleep is theta waves?

Stage Two sleep

The theta waves characteristic of Stage Two sleep are interrupted by occasional series of high-frequency waves known as sleep spindles. These bursts of activity have a frequency of eight to fourteen Hz and an amplitude of 50 to 150 µV.

Does stage 2 sleep have theta waves?

As we move into stage 2 sleep, the body goes into a state of deep relaxation. Theta waves still dominate the activity of the brain, but they are interrupted by brief bursts of activity known as sleep spindles (Figure SC.

Which waves are to wakefulness and which waves are to deep sleep?

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 ([link]). During this time, an individual’s heart rate and respiration slow dramatically.

During which stage of sleep do sleep spindles and K-complexes appear quizlet?

In Stage 2 EEG shows SLEEP SPINDLES (brief bursts of high frequency periodically appear. The presence of these indicate that the person is truly asleep. EEG patterns also show K COMPLEXES, which are bursts of low frequency and slightly higher amplitude waves.

What are sleep spindles and K complexes?

K complexes are large waves that stand out from the background and often occur in response to environmental stimuli such as sounds in the bedroom. Sleep spindles are brief bursts of fast activity that appear something like the shape of an “eye” as they rapidly increase in amplitude and then rapidly decay.

Which stage of sleep typically follows Stage 4 sleep quizlet?

Following stage 4, the sleeper enters REM sleep, where dreaming occurs. A cycle of sleep (stages 1 to 4 followed by a period of REM) lasts approximatly 90 minutes. Since we sleep an average of 8 hours, there are 5 such cycles per night and therefore 5 dreams per night.

What are the 4 stages of sleep quizlet?

Terms in this set (6)

  • Stage 1. transition from wakefulness and sleep. Lasts 1-7 minutes. …
  • Stage 2. Beginning of sleep, high frequency bursts of brain activity called Sleep Spindles. …
  • Stage 3. Deep Sleep.
  • Stage 4. Deep Sleep. …
  • Non-REM Sleep. where you spend 80% of your sleep time. …
  • REM Sleep. 205 of your sleep time.

What are the 5 stages of sleep quizlet?

Terms in this set (5)

  • Stage 1: -Light sleep~ Theta sleep (4-7 CPS) -Hypnic jerk. …
  • Stage 2: -Light sleep, theta waves (4-7 CPS) -slightly deeper stage of sleep. …
  • Stage 3: -Deep sleep, Delta waves (less than 4 CPS)
  • Stage 4: -Purely delta waves (close to 1 CPS) -the deepest stage of sleep. …
  • Stage 5: -Rapid Eye Movement.

What happens to Stages 3 and 4 sleep as the night progresses quizlet?

We spend less time in stage 3 and 4 sleep as the night progresses, and more in REM. The period between being asleep and waking up, when brainwaves are predominantly alpha waves.

Which of the following are happening during stages 3 and 4 of sleep?

In stage 3, extremely slow brain waves called delta waves begin to appear, interspersed with smaller, faster waves. By stage 4, the brain produces delta waves almost exclusively. It is very difficult to wake someone during stages 3 and 4, which together are called deep sleep.

What happens during Stage 1 NREM sleep quizlet?

In this stage of sleep, alpha waves are replaced with theta waves. In this stage, and individual’s eye roll slowly, muscles relax and heart and breathing rate decreases. Occurs during stage 1 NREM sleep, characterized by medium frequency brainwaves with mixed amplitudes.

What term do sleep researchers designate stages 1 through 3 of sleep?

N1 sleep: N1 refers to the first stage of NREM sleep and is also known as stage 1. N2 sleep: N2 is the second stage of NREM sleep, also known as stage 2. N3 sleep: N3 is the third and final stage of NREM sleep and is also known as stage 3, deep sleep, delta sleep, or slow-wave sleep.

What happens during stage 1 sleep psychology quizlet?

Stage 1 can be considered a transition period between wakefulness and sleep. In Stage 1, the brain produces high amplitude theta waves, which are very slow brain waves. This period of sleep lasts only a brief time (around 5-10 minutes).