Letting Eyewitnesses Sleep Could Make For More Accurate Testimony

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iStock

Despite what watching Law & Order might have taught you, eyewitness accounts of crimes are far from trustworthy. Human memory is fallible, and in fact, eyewitnesses are notoriously bad at providing accurate evidence. Misidentification by eyewitnesses has played a role in 70 percent of convictions overturned by DNA evidence in the U.S., according to the New York-based Innocence Project. But a new study suggests one way to help eyewitnesses provide more accurate evidence: sleep.

Published in the journal PLOS ONE and spotted by Futurity, the study finds that witness testimony is more accurate during police lineups if the person is well-rested.

In the study, Michigan State University students watched a video of a staged crime in which a man planted a bomb on a rooftop. They were then asked to look through several black-and-white lineups of six people, some of which included the perpetrator from the video, and some of which only had look-alike fillers. The participants had to wait 12 hours between watching the video and picking out the criminal from the lineup, but not all of them spent it the same way. Some watched the video in the morning and looked at the lineup at night, while others watched the video at night and then looked at the lineup in the morning, after they had slept.

The researchers found that when participants slept between seeing the “crime” and being presented with potential suspects, they were less likely to pick someone out of lineups that only included fillers. In other words, they were better able to reject innocent lookalikes, noting correctly that the perpetrator they had seen wasn’t present at all. People who had not slept misidentified an innocent person as the perpetrator 66 percent of the time compared to 42 percent of the people who had slept. That doesn’t seem like a huge difference, but even one misidentification in real life can have serious consequences for innocent people accused of crimes. The results track with existing research on sleep that has found that it plays an important role in cognitive processes like learning and memory.

However, sleep didn’t make the participants any better at identifying the correct suspect when he was in the lineup. Both groups could pick him out with about 50 percent accuracy. Essentially, sleep isn’t going to solve crimes, but it could help ensure that the wrong person doesn’t go to prison.

Previously, a 2016 study in Psychological Science found that it’s relatively easy for police to nudge witnesses into picking their prime suspect from a lineup by making sure that they’re the only person in the group with a particular distinguishing feature, like a beard. These unfair lineups not only resulted in misidentification, but participants who chose from them were more confident about their (incorrect) choice than people who saw more fair lineups.

Taking a long nap isn’t the only way to improve lineup accuracy. The criminal justice advocates at the Innocence Project recommend several methods to make sure that witness testimony is more accurate, such as making sure that the people shown in the lineups all roughly match the description of suspect (beard and all), having the lineup administered by an officer who doesn’t know which person in the lineup is the police’s suspect, and making sure the witnesses know that the perpetrator might not be in the lineup at all, and that the investigation will continue even if they don’t pick anyone.

[h/t Futurity]

10 of the Best Indoor and Outdoor Heaters on Amazon

Mr. Heater/Amazon
Mr. Heater/Amazon

With the colder months just around the corner, you might want to start thinking about investing in an indoor or outdoor heater. Indoor heaters not only provide a boost of heat for drafty spaces, but they can also be a money-saver, allowing you to actively control the heat based on the rooms you’re using. Outdoor heaters, meanwhile, can help you take advantage of cold-weather activities like camping or tailgating without having to call it quits because your extremities have gone numb. Check out this list of some of Amazon’s highest-rated indoor and outdoor heaters so you can spend less time shivering this winter and more time enjoying what the season has to offer.

Indoor Heaters

1. Lasko Ceramic Portable Heater; $20

Lasko/Amazon

This 1500-watt heater from Lasko may only be nine inches tall, but it can heat up to 300 square feet of space. With 11 temperature settings and three quiet settings—for high heat, low heat, and fan only—it’s a dynamic powerhouse that’ll keep you toasty all season long.

Buy it: Amazon

2. Alrocket Oscillating Space Heater; $25

Alrocket/Amazon

Alrocket’s oscillating space heater is an excellent addition to any desk or nightstand. Using energy-saving ceramic technology, this heater is made of fire-resistant material, and its special “tip-over” safety feature forces it to turn off if it falls over (making it a reliable choice for homes with kids or pets). It’s extremely quiet, too—at only 45 dB, it’s just a touch louder than a whisper. According to one reviewer, this an ideal option for a “very quiet but powerful” heater.

Buy it: Amazon

3. De’Longhi Oil-Filled Radiator Space Heather; $79

De’Longhi/Amazon

If you prefer a space heater with a more old-fashioned vibe, this radiator heater from De’Longhi gives you 2020 technology with a vintage feel. De’Longhi’s heater automatically turns itself on when the temperatures drops below 44°F, and it will also automatically turn itself off if it starts to overheat. Another smart safety feature? The oil system is permanently sealed, so you won’t have to worry about accidental spills.

Buy it: Amazon

4. Aikoper Ceramic Tower Heater; $70

Aikoper/Amazon

Whether your room needs a little extra warmth or its own heat source, Aikoper’s incredibly precise space heater has got you covered. With a range of 40-95°F, it adjusts by one-degree intervals, giving you the specific level of heat you want. It also has an option for running on an eight-hour timer, ensuring that it will only run when you need it.

Buy it: Amazon

5. Isiler Space Heater; $37

Isiler/Amazon

For a space heater that adds a fun pop of color to any room, check out this yellow unit from Isiler. Made from fire-resistant ceramic, Isiler’s heater can start warming up a space within seconds. It’s positioned on a triangular stand that creates an optimal angle for hot air to start circulating, rendering it so effective that, as one reviewer put it, “This heater needs to say ‘mighty’ in its description.”

Buy it: Amazon

Outdoor Heaters

6. Mr. Heater Portable Buddy; $104

Mr. Heater/Amazon

Make outdoor activities like camping and grilling last longer with Mr. Heater’s indoor/outdoor portable heater. This heater can connect to a propane tank or to a disposable cylinder, allowing you to keep it in one place or take it on the go. With such a versatile range of uses, this heater will—true to its name—become your best buddy when the temperature starts to drop.

Buy it: Amazon

7. Hiland Pyramid Patio Propane Heater; Various

Hiland/Amazon

The cold’s got nothing on this powerful outdoor heater. Hiland’s patio heater has a whopping 40,000 BTU output, which runs for eight to 10 hours on high heat. Simply open the heater’s bottom door to insert a propane tank, power it on, and sit back to let it warm up your backyard. The bright, contained flame from the propane doubles as an outdoor light.

Buy it: Amazon

8. Solo Stove Bonfire Pit; $345

Solo Stove/Amazon

This one is a slight cheat since it’s a bonfire pit and not a traditional outdoor heater, but the Solo Stove has a 4.7-star rating on Amazon for a reason. Everything about this portable fire pit is meticulously crafted to maximize airflow while it's lit, from its double-wall construction to its bottom air vents. These features all work together to help the logs burn more completely while emitting far less smoke than other pits. It’s the best choice for anyone who wants both warmth and ambiance on their patio.

Buy it: Amazon

9. Dr. Infrared Garage Shop Heater; $119

Dr. Infrared/Amazon

You’ll be able to use your garage or basement workshop all season long with this durable heater from Dr. Infrared. It’s unique in that it includes a built-in fan to keep warm air flowing—something that’s especially handy if you need to work without wearing gloves. The fan is overlaid with heat and finger-protectant grills, keeping you safe while it’s powered on.

Buy it: Amazon

10. Mr. Heater 540 Degree Tank Top; $86

Mr. Heater/Amazon

Mr. Heater’s clever propane tank top automatically connects to its fuel source, saving you from having to bring any extra attachments with you on the road. With three heat settings that can get up to 45,000 BTU, the top can rotate 360 degrees to give you the perfect angle of heat you need to stay cozy. According to a reviewer, for a no-fuss outdoor heater, “This baby is super easy to light, comes fully assembled … and man, does it put out the heat.”

Buy it: Amazon

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Your Tattoos Could Be Messing With Your Sweat Glands

Tattoos might inhibit a person's ability to sweat.
Tattoos might inhibit a person's ability to sweat.
vgajic/iStock via Getty Images

For centuries, tattoos have reflected cultural traditions, personal beliefs, self-expression, and one’s preferred motorcycle club affiliation. But those who have used their bodies as a giant canvas for permanent ink with meaning might have a little trouble cooling off. That’s because tattoos might actually be interfering with sweating, according to a new study.

A paper published in the Journal of Applied Physiology recruited 10 subjects with tattoos and had them wear tube-lined suits containing warm water. When fitted against the skin, the warmth induced sweating. Skin covered by a tattoo produced roughly 15 percent less sweat than unmarked skin in the same subject.

While the sample size was small, the study follows other research into the effects of tattooing on sweat glands. In 2017, Alma College’s Maurie Luetkemeier used an electric current to produce sweat and found inked skin produced 50 percent less sweat, though the method to promote the sweat was considerably different than how the body cools itself naturally. Another study used exercise to observe sweating and found no difference in tattooed and non-tattooed skin.

This latest research seems to indicate that thermal-induced sweating can indeed be interrupted by tattoo ink and that a person’s sweat glands suffer an undetermined amount of damage as a result of being tattooed, which involves a needle being inserted into the skin’s dermal layer. While further research will be needed to make more solid conclusions, it’s something to consider the next time you ponder getting that full-back dragon rendering.

[h/t New Atlas]