Health

The science behind why your body jerks when you fall asleep

Have you ever gone to sleep at night and dreamt that you were falling? Then suddenly, your body jerks, and you are startled awake. An experience like this can…
The science behind why your body jerks when you fall asleep

Have you ever gone to sleep at night and dreamt that you were falling? Then suddenly, your body jerks, and you are startled awake. An experience like this can be somewhat unsettling, but if it’s happened to you, you’re not alone. This strange occurrence is called a hypnic jerk, and a 2016 study found that sixty to seventy percent of people experience them [1].

The Stages of Sleep
The science behind why your body jerks when you fall asleep
Before getting into the cause of these hypnic jerks, let’s first do a refresher on the stages of sleep:

Stage One

This is what happens when you first start nodding off. This short period lasts several minutes. During this time your heartbeat, breathing, and eye movements slow, and your muscles relax with occasional twitches. Your brainwaves also begin to slow from their wakefulness patterns.

Stage Two

This is a period of light sleep before you enter a deeper sleep. Here, your heartbeat and breathing slow, and your muscles relax even further. Your body temperature drops and eye movements stop. Your brain activity also slows, but you experience occasional bursts of electrical activity.

Stage Three

You need stage three to feel refreshed in the morning. This is when your heartbeat and muscles are at their slowest, your muscles are relaxed, and it might be difficult to wake you.

REM Sleep

Rapid eye movement sleep occurs about ninety minutes after you fall asleep. Your eyes move rapidly from side to side and your brain wave activity becomes closer to that of wakefulness. Your breathing becomes faster and irregular, and your heart rate and blood pressure increase, almost to waking levels. This is when most of your dreaming takes place. You cycle through these stages four or five times every night. Depending on what cycle you’re in, the stages will vary in length [2].

Hypnic Jerks

Hypnic jerks are basically involuntary sleep movements that occur as you transition from wakefulness to sleep. They are sometimes referred to as hypnagogic jerks or sleep starts. They are not very well understood, however, they do tend to occur more often when you’re trying to force your brain to engage in an activity when you’re sleep-deprived. Rafael Pelayo, a sleep specialist at the Stanford Sleep Medicine Center, says that it’s because certain parts of your nervous system are awake, while others are asleep.

Recommended Article Teen athlete Austin Metcalf’s final post is heartbreaking

Essentially, you can think of a hypnic jerk as a misfire caused by your nervous system sending your body mixed messages. Generally, they occur when you’re transitioning from wakefulness into stage one of sleep. As explained, REM sleep typically occurs ninety minutes after falling asleep. When you’re really sleep-deprived, however, you go straight from stage one to REM sleep. You basically skip right over stages two and three. Paleyo says that a hypnic jerk is a clear sign from the body that you need to sleep. “Nothing else is going to satisfy that urge.” [3]

Are Hypnic Jerks Dangerous?

Luckily, no. Hypnic jerks, while they can be scary at the moment, are benign and do not need to be treated. Some may feel anxious after experiencing one and have difficulty falling back to sleep. If this happens to you, try to remind yourself that it doesn’t mean anything and that there’s nothing wrong. This may help to ease your mind so you can go back to sleep.

Hypnic Jerks and Lack of Sleep

Sometimes, though, you may experience a hypnic jerk when sleep is not an option. For some, they can occur when they’re over tired in a class lecture or a meeting. If this is the case, Palayo has a few suggestions:

Focus on something that’s more important about that scenario than falling asleep.
Make eye contact with the speaker.
Drink coffee beforehand if you know you’re going to have trouble staying alert.
Make sure to get seven to nine hours of sleep every night to avoid being over-tired [3].

While hypnic jerks are not dangerous, they are a sign that you’re not getting enough sleep. If you notice them happening frequently, ask yourself why you might be over-tired and consider making some changes.

Have you read them?

The Naked Gun Trailer Teases Liam Neeson in Strawberry-Pink Underwear and an O.J. Simpson Joke

Here’s Why You Shouldn’t Sleep With A Fan At Night

How Water Fasting Can Regenerate the Immune System, Slow Aging, Reduce Heart Attack Risk and More

Ex-Yankees star Brett Gardner’s son Miller died from silent killer

News Feed

04.04.2025 17:10 News

Teen athlete Austin Metcalf’s final post is heartbreaking

04.04.2025 17:05 Celebrities

Glen Powell Shares Marriage Desires After Attending Sister’s Wedding Alongside Sydney Sweeney: ‘Want to Do it Right’

04.04.2025 17:01 Health

9 Early Signs of Diabetes You May Not Be Noticing

04.04.2025 16:56 Tips & Tricks

Did you know: When a Spider visits your home it’s a sign

04.04.2025 16:52 Celebrities

‘Baywatch’ alum Donna D’Errico slammed for seductive snaps

04.04.2025 16:47 Celebrities

The Naked Gun Trailer Teases Liam Neeson in Strawberry-Pink Underwear and an O.J. Simpson Joke

04.04.2025 16:24 Health

Here’s Why You Shouldn’t Sleep With A Fan At Night

04.04.2025 16:18 Health

How Water Fasting Can Regenerate the Immune System, Slow Aging, Reduce Heart Attack Risk and More

04.04.2025 16:15 Celebrities

Ex-Yankees star Brett Gardner’s son Miller died from silent killer

04.04.2025 16:11 Celebrities

Paradise’s Sarah Shahi ‘Heard’ Her Dog Get Attacked and Taken by a Coyote: ‘My Heart Is in Pieces’

04.04.2025 16:08 Spotlight

Very few people see all the faces in this picture – how many can you find?

04.04.2025 16:04 Stories

I broke down saying goodbye to my K9- partner…

04.04.2025 15:23 Celebrities

Elon Musk’s Estranged Daughter Shuts Down Katniss Everdeen Comparisons: ‘I Was Born into the Aristocracy’

04.04.2025 15:21 Spotlight

Find The Correct Shadow.

04.04.2025 15:18 Health

If You See These Painful Red Bumps, Here’s What It Really Means

04.04.2025 15:14 America

High school track meet turns tragic: Texas teen fatally stabbed by fellow student

04.04.2025 15:10 Celebrities

Tom Hanks’ Daughter E.A. Hanks Reflects on Troubled Childhood After Parents’ Divorce in New Book

04.04.2025 15:06 Items

Rediscovering the Marvel of Simplicity

04.04.2025 15:02 Stories

My Mom Thought No Man Was Good Enough for Me Until One Invited Her on a Date

04.04.2025 14:55 Celebrities

Hailey Okula dies during childbirth after 2-year struggle to get pregnant

03.04.2025 23:17 Celebrities

Tom Cruise Breaks Silence on ‘Top Gun’ Costar Val Kilmer’s Death

03.04.2025 23:14 Tips & Tricks

What’s The Purpose Of The Fabric Strip Across Hotel Beds

03.04.2025 23:11 Health

The nose knows: Unraveling the enigmatic link between the sense of smell and mortality

03.04.2025 23:08 Spotlight

You Won’t Believe Which Coin Hits the Bottom First—The Answer Will Blow Your Mind!

03.04.2025 23:03 News

Teen Idol Johnny Tillotson, known for ‘Poetry in Motion,’ has passed away

03.04.2025 22:56 Celebrities

Michelle Williams Quietly Welcomed Baby No. 4 Via Surrogate, Her 3rd With Husband Thomas Kail

03.04.2025 22:52 Health

Why Nobody Should Be Eating Salmon Anymore

03.04.2025 22:47 Celebrities

Kurt Russell says Val Kilmer gave him a dark gift after filming Tombstone

03.04.2025 22:44 News

Nursing Influencer Hailey Okula’s Cause of Death Revealed After She Dies Due to ‘Complications from Childbirth’ of First Baby

03.04.2025 22:36 Spotlight

The meaning of wearing ankle bracelets

Exit mobile version