Stages of Sleep

Stage 3

Deep, slow brain waves known as Delta Waves begin to emerge during this stage. It is a transitional period between light sleep and a very deep sleep.

Alpha Waves

It's a restful place. During this stage, it's not unusual to experience strange and extremely vivid sensations or a feeling of falling followed by sudden muscle contractions. These are known as hypnogogic hallucinations. You may even feel like you are hearing someone call your name, or the phone ringing.

Theta Waves

Present during deep meditation and light sleep, including the all-important REM dream state. It is only experienced momentarily as you drift off to sleep from Alpha and wake from deep sleep (from Delta).

Stage 4

This is sometimes referred to as Delta Sleep because of the delta waves that occur during this time. Stage Four is a deep sleep that lasts for about 30 minutes. Sleepwalking and bed-wetting typically happen at the end of Stage Four sleep.

Stage 2

This stage of sleep lasts about 20 minutes. Our brain begins to produce very short periods of rapid, rhythmic brain wave activity known as Sleep Spindles. Body temperature begins dropping and heart rate starts slowing down.

Stage 1

When we are preparing to drift off, we go though Alpha and Theta, and have periods of dreaminess, almost like daydreaming, except we are beginning to fall asleep. These are interesting states, in that we experience them throughout the day and some people may have more of these waves than others. We then begin to enter Theta, which is still a relatively light period between being awake and asleep. This usually lasts for 5-10 minutes. Research has shown that the average sleeper takes about 7 minutes to fall asleep. You may fall asleep sooner, or take longer.

Beta Waves

Associated with normal waking consciousness and a heightened state of alertness, logic and critical reasoning. Important for effective functioning throughout the day, they also can translate into stress, anxiety and restlessness.

Stage 5

Most dreaming occurs during this stage, known as REM. REM sleep is characterized by eye movement, increased respiration rate and increased brain activity. REM sleep is also referred to as paradoxical sleep because, while the brain and other body systems become more active, your muscles become more relaxed, or paralyzed. Dreaming occurs because of increased brain activity, but voluntary muscles become paralyzed. Voluntary muscles are those that you need to move by choice, for example, your arms and legs. Involuntary muscles are those that include your heart and gut. They move on their own. Rapid eye movement, or REM sleep, is when you typically dream. You may have images float by in earlier stages, particularly when you are going through Alpha or Theta, but the actual dream state occurs in REM. This period of paralyzation is a built-in protective measure to keep you from harming yourself. When you are paralyzed, you can't leap out of bed and run. Do you ever feel like you can't escape during a dream? Well, the truth is, you can't. You can breathe, and your heart is working, but you really can't move.