Why Aren't You Supposed to Wake a Sleepwalker?

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iStock

Reader Gabrielle wrote in to ask: “Why can't we wake a sleepwalker? Is it a can't do, or a shouldn't do?”

Despite urban legends claiming that waking a sleepwalker will send them into shock or give them a heart attack, it’s pretty much harmless. While you can wake them up, you probably shouldn’t, and that’s for both your benefit.

Waking a sleepwalker has never been shown to cause them any harm, but there’s plenty of potential for the person doing the waking to get hurt. Sleepwalking usually occurs during Stage 3 non-rapid eye movement sleep, also known as slow wave sleep, and this stage of sleep is very deep. While waking straight from stage 3 is difficult, it can be done—but doing so can leave a person in a state of cognitive impairment (sleep scientists call it sleep inertia) for around 30 minutes.

Sleep experts warn that forcefully bringing a person out of a deep sleep into this impaired state can cause them to become startled, confused or agitated. Not immediately recognizing you as someone they know, they may push you, strike you, or otherwise lash out at you. Even if they don’t react aggressively, some sleepwalkers have been known to drive or prepare meals in their sleep, and having a groggy, confused person behind the wheel or at the stove can be dangerous for them and for others.

Instead of trying to wake a sleepwalker, the Sleep Disorders Center at NYU recommends gently leading them by the arm to guide them back to bed.

Take Advantage of Amazon's Early Black Friday Deals on Tech, Kitchen Appliances, and More

Amazon
Amazon

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Even though Black Friday is still a few days away, Amazon is offering early deals on kitchen appliances, tech, video games, and plenty more. We will keep updating this page as sales come in, but for now, here are the best Amazon Black Friday sales to check out.

Kitchen

Instant Pot/Amazon

- Instant Pot Duo Plus 9-in-115 Quart Electric Pressure Cooker; $90 (save $40) 

- Le Creuset Enameled Cast Iron Signature Sauteuse 3.5 Quarts; $180 (save $120)

- KitchenAid KSMSFTA Sifter with Scale Attachment; $95 (save $75) 

- Keurig K-Mini Coffee Maker; $60 (save $20)

- Cuisinart Bread Maker; $88 (save $97)

- Anova Culinary Sous Vide Precision Cooker; $139 (save $60)

- Aicook Juicer Machine; $35 (save $15)

- JoyJolt Double Wall Insulated Espresso Mugs - Set of Two; $14 (save $10) 

- Longzon Silicone Stretch Lids - Set of 14; $13 (save $14)

HadinEEon Milk Frother; $37 (save $33)

Home Appliances

Roomba/Amazon

- iRobot Roomba 675 Robot Vacuum with Wi-Fi Connectivity; $179 (save $101)

- Fairywill Electric Toothbrush with Four Brush Heads; $19 (save $9)

- ASAKUKI 500ml Premium Essential Oil Diffuser; $22 (save $4)

- Facebook Portal Smart Video Calling 10 inch Touch Screen Display with Alexa; $129 (save $50)

- Bissell air320 Smart Air Purifier with HEPA and Carbon Filters; $280 (save $50)

Oscillating Quiet Cooling Fan Tower; $59 (save $31) 

TaoTronics PTC 1500W Fast Quiet Heating Ceramic Tower; $55 (save $10)

Vitamix 068051 FoodCycler 2 Liter Capacity; $300 (save $100)

AmazonBasics 8-Sheet Home Office Shredder; $33 (save $7)

Ring Video Doorbell; $70 (save $30) 

Video games

Sony

- Marvel's Spider-Man: Game of The Year Edition for PlayStation 4; $20 (save $20)

- Marvel's Avengers; $27 (save $33)

- Minecraft Dungeons Hero Edition for Nintendo Switch; $20 (save $10)

- The Last of Us Part II for PlayStation 4; $30 (save $30)

- LEGO Harry Potter: Collection; $15 (save $15)

- Ghost of Tsushima; $40 (save $20)

BioShock: The Collection; $20 (save $30)

The Sims 4; $20 (save $20)

God of War for PlayStation 4; $10 (save $10)

Days Gone for PlayStation 4; $20 (save $6)

Luigi's Mansion 3 for Nintendo Switch; $40 (save $20)

Computers and tablets

Microsoft/Amazon

- Apple MacBook Air 13 inches with 256 GB; $899 (save $100)

- New Apple MacBook Pro 16 inches with 512 GB; $2149 (save $250) 

- Samsung Chromebook 4 Chrome OS 11.6 inches with 32 GB; $210 (save $20) 

- Microsoft Surface Laptop 3 with 13.5 inch Touch-Screen; $1200 (save $400)

- Lenovo ThinkPad T490 Laptop; $889 (save $111)

- Amazon Fire HD 10 Tablet (64GB); $120 (save $70)

- Amazon Fire HD 10 Kids Edition Tablet (32 GB); $130 (save $70)

- Samsung Galaxy Tab A 8 inches with 32 GB; $100 (save $50)

Apple iPad Mini (64 GB); $379 (save $20)

- Apple iMac 27 inches with 256 GB; $1649 (save $150)

- Vankyo MatrixPad S2 Tablet; $120 (save $10)

Tech, gadgets, and TVs

Apple/Amazon

- Apple Watch Series 3 with GPS; $179 (save $20) 

- SAMSUNG 75-inch Class Crystal 4K Smart TV; $998 (save $200)

- Apple AirPods Pro; $169 (save $50)

- Nixplay 2K Smart Digital Picture Frame 9.7 Inch Silver; $238 (save $92)

- All-New Amazon Echo Dot with Clock and Alexa (4th Gen); $39 (save $21)

- MACTREM LED Ring Light 6" with Tripod Stand; $16 (save $3)

- Anker Soundcore Upgraded Bluetooth Speaker; $22 (save $8)

- Amazon Fire TV Stick with Alexa Voice Remote; $28 (save $12)

Canon EOS M50 Mirrorless Camera with EF-M 15-45mm Lens; $549 (save $100)

DR. J Professional HI-04 Mini Projector; $93 (save $37)

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Why Doesn’t the U.S. Use the Metric System?

Choose your fighter.
Choose your fighter.
William Warby, Unsplash

After the French Revolution in the late 18th century, the fledgling French republic devised a new unit of measurement called the “meter”—one ten-millionth of the distance between the North Pole and the equator. That became the basis for the metric system, which was eventually adopted in many other countries around the world.

The U.S. wasn’t among them. Though Thomas Jefferson did show interest in the system when he was secretary of state in the 1790s, no change ever came to fruition. According to Northwestern University history professor Ken Alder, Americans may have simply been resistant to the idea of standardizing something on a global scale. “I understand when people resent it as a remote force of globalization that produces uniformity, and it's perfectly rational to want local control,” he told Live Science. “It can also be about taking a position against something that's hyperrational and French.”

Furthermore, Britain’s Industrial Revolution began to take hold in the U.S. during the 1800s, and most manufacturers were calibrating machinery and measuring products using inches, pounds, and all the other familiar units of Britain’s imperial system. As Encyclopaedia Britannica explains, shifting to the metric system would’ve been laborious and costly; whenever Congress brought it up, business owners and citizens quickly shut it down. Two centuries later, those same issues continue to keep the U.S. from committing to the metric system.

That’s not to say we haven’t tried. In 1975, Congress passed the Metric Conversion Act, which encouraged businesses to transition to metric units of measurement. Since it wasn’t mandatory—and imperial units would still be accepted—it hardly upended the status quo. Later that decade, President Jimmy Carter spearheaded a campaign to swap miles for kilometers on road signage, but that didn’t stick, either.

Alder pointed out that France was probably only able to implement a whole new system because the country was in a state of complete upheaval at the time, and many other old processes were changing, too. Britain was also undergoing a large-scale political renovation when it finally switched to the metric system in the 1970s. Because the U.S. government has been relatively static since the formation of the Constitution, we haven’t had a similar opportunity.