The Stages of Sleep Explained – What Happens During REM and Non-REM Sleep

Sleep is vital for our health, cognitive function, and overall well-being. Yet many people don’t fully understand the different stages of sleep and what happens during each stage. In this blog post, we’ll provide an overview of the various stages of sleep and the characteristics of REM (rapid eye movement) and non-REM sleep.

The Stages of Sleep

There are two main types of sleep: non-REM and REM sleep. Non-REM sleep progresses through three different stages:

 

Stage 1: This is light sleep where you are easily woken up. Your muscles relax, your heartbeat slows, and brain activity begins to slow.

 

Stage 2: This is deeper sleep with increased brain wave activity. You become disengaged from your surroundings. This stage accounts for about half of the total sleep time.

 

Stage 3: This is the deepest stage of non-REM sleep. It’s harder to wake someone up during this restorative stage. Muscles are relaxed, blood pressure drops, and breathing slows.

 

After deep non-REM sleep, we enter REM sleep where dreaming occurs due to increased brain activity.

 

REM Sleep

REM sleep first occurs about 90 minutes after falling asleep. Your brain activity increases during REM, similar to when you’re awake. Your eyes move rapidly behind closed eyelids. As brain activity increases, you start to dream vividly. The body becomes immobile and relaxed, with muscles inactive to prevent acting out dreams.

 

REM sleep is crucial for memory consolidation and learning. The increased brain activity transfers and processes memories from short-term to long-term storage.

 

Non-REM Sleep

Non-REM sleep makes up about 75 percent of total sleep time. Stages 3 and 4, the deep stages, are most important for physical recovery. Your immune system functions most actively during deep sleep, working to heal and protect the body.

 

Growth and tissue repair also occur predominantly during deep non-REM sleep. The body releases hormones that restore muscles and tissues. Overall, non-REM sleep is vital for your body’s rejuvenation.

The Sleep Cycle

We cycle between non-REM and REM sleep several times throughout the night. Each complete sleep cycle lasts around 90 minutes. Most people experience four to six sleep cycles per night. Quality sleep means spending sufficient time in both deep non-REM and active REM sleep.

 

Getting adequate deep non-REM and REM sleep is vital for learning, memory retention, overall health, and well-being. Understanding the different stages of sleep gives us insight into how sleep works and why it’s so important for optimal rest. Pay attention to your sleep needs and aim to get enough deep and REM sleep every night.

 

Expert Care for Your Sleep Needs

If you’re having trouble sleeping or want to learn more about improving your sleep quality, be sure to contact us. Dr. Simmons can provide customized advice and effective treatment plans to help you get the restful sleep your body and mind need. Schedule a consultation with Dr. Simmons by calling (818) 300-0070. Investing in your sleep health is one of the best things you can do for your overall well-being. Dr. Simmons looks forward to helping you achieve restful, rejuvenating nights and increased energy during the day.