Does Self-Control Deplete Over the Course of the Day? Maybe Not, Says New Study

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iStock

For months now, I’ve been trying to cut out sugar from my diet. I’ve read about all the ways my sweet tooth will be the death of me, and I’ve resolved to give it up. And yet, even as I write this, my long-term goal to eat healthy is losing out to my eternal desire to eat M&Ms at my desk. Is it because it’s the end of the day, and I’ve been trying to make choices for eight hours already? Or is it something else?

A new study in PLOS One pushes back on the popular theory known as "ego depletion," which hypothesizes that self-control is a finite resource that depletes throughout the day, much like energy levels. Instead, researchers from the University of Toronto and the learning technology company Cerego found that people's self-control depletes when it comes to doing one task for a long period of time, but that self-control fatigue isn't a factor when you're switching tasks. In other words, it's hard to say no to the box of cookies all day long, but saying no to the box of cookies won't impede other acts of self-control, like your ability to focus on your homework instead of turning on the TV.

The study used data from Cerego, which publishes online study materials, examining the study behaviors of two groups of college students using the Cerego system as part of semester-long psychology courses. The researchers looked at data from two groups of users, one group of 8700 students and one of almost 8800, focusing on how long they worked during each session and how well they performed at the memory tests within the curriculum.

If self-control really is a finite resource, it should be depleted by the end of the day, after people presumably have spent many hours resisting their first impulses in one way or another. But the researchers found that this wasn't true. Overall, students didn't do any better if they used the program earlier in the morning. Instead, performances peaked around 2 p.m., and people logged in to use the software more and more as the day went on, suggesting that the motivation to learn doesn't fall off at night (though that may also be because that's when college students do their homework in general).

However, mental resources did seem to be drained by doing the same task for a long period of time. The researchers found that after a certain point, students' performance dropped off, peaking at about 28 minutes of work. They made about 5 percent more mistakes 50 minutes into the session compared to that peak.

When it comes to the idea that we exhaust our store of self-control, the authors write, "the notion that this fatigue is completely fluid, and that it emerges after minutes of self-control, is under considerable doubt."

The notion of ego depletion comes from a 1998 study in which researchers asked participants to hang out in a room full of fresh-baked cookies, telling them to eat only from a bowl of radishes, leaving the cookies untouched. Then, those volunteers worked on an impossible puzzle. Volunteers who had spent time avoiding the delicious pull of cookies gave up on the mind-boggling task an average of 11 minutes earlier than a group of volunteers who were brought into the same room and allowed to eat as many cookies as they wanted. (Lucky them.)

Since then, the idea has taken off, leading to hundreds of subsequent studies and even influencing the habits of people like Barack Obama, who told Vanity Fair in 2011 that he only wore blue or gray suits in order to cut down on the non-vital decisions he had to make throughout the day.

This current study isn't the first to challenge the theory’s veracity, though. In 2016, a 2000-person replication study by some of the same authors (with scientists in 23 different labs) pushed back on the theory of ego depletion, finding that short spurts of self-control didn't have any effect on subsequent tasks. This study just adds to the evidence against the well-established idea.

So it's looking more and more like ego depletion isn't a good excuse for my afternoon vending-machine habit. Perhaps the true secret to excellent self-control is this: Just be a raven.

6 Protective Mask Bundles You Can Get On Sale

pinkomelet/iStock via Getty Images Plus
pinkomelet/iStock via Getty Images Plus

Daily life has changed immeasurably since the onset of COVID-19, and one of the ways people have had to adjust is by wearing protective masks out in public places, including in parks and supermarkets. These are an essential part of fighting the spread of the virus, and there are plenty of options for you depending on what you need, whether your situation calls for disposable masks to run quick errands or the more long-lasting KN95 model if you're going to work. Check out some options you can pick up on sale right now.

1. Cotton Face Masks; $20 for 4

Protective Masks with Patterns.
Triple7Deals

This four-pack of washable cotton face masks comes in tie-dye, kids patterns, and even a series of mustache patterns, so you can do your part to mask germs without also covering your personality.

Buy it: $20 for four (50 percent off)

2. CE- and FDA-Approved KN95 Mask; $50 for 10

A woman putting on a protective mask.
BetaFresh

You’ve likely heard about the N95 face mask and its important role in keeping frontline workers safe. Now, you can get a similar model for yourself. The KN95 has a dual particle layer, which can protect you from 99 percent of particles in the air and those around you from 70 percent of the particles you exhale. Nose clips and ear straps provide security and comfort, giving you some much-needed peace of mind.

Buy it: $50 for 10 (50 percent off)

3. Three-Ply Masks; $13 for 10

Woman wearing a three-ply protective mask.
XtremeTime

These three-ply, non-medical, non-woven face masks provide a moisture-proof layer against your face with strong filtering to keep you and everyone around you safe. The middle layer filters non-oily particles in the air and the outer layer works to block visible objects, like droplets.

Buy it: $13 for 10 (50 percent off)

4. Disposable masks; $44 for 50

A batch of disposable masks.
Odash, Inc.

If the thought of reusing the same mask from one outing to the next makes you feel uneasy, there’s a disposable option that doesn’t compromise quality; in fact, it uses the same three-layered and non-woven protection as other masks to keep you safe from airborne particles. Each mask in this pack of 50 can be worn safely for up to 10 hours. Once you're done, safely dispose of it and start your next outing with a new one.

Buy it: $44 for 50 (41 percent off)

5. Polyester Masks; $22 for 5

Polyester protective masks.
Triple7Deals

These masks are a blend of 95 percent polyester and 5 percent spandex, and they work to block particles from spreading in the air. And because they're easily compressed, they can travel with you in your bag or pocket, whether you're going to work or out to the store.

Buy it: $22 for five (56 percent off)

6. Mask Protector Cases; $15 for 3

Protective mask case.
Triple7Deals

You're going to need to have a stash of masks on hand for the foreseeable future, so it's a good idea to protect the ones you’ve got. This face mask protector case is waterproof and dust-proof to preserve your mask as long as possible.

Buy it: $15 for three (50 percent off)

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Tear Gas vs. Pepper Spray: What’s the Difference?

This is probably pepper spray.
This is probably pepper spray.
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Pepper spray and tear gas are both non-lethal irritants that cause extreme burning of the eyes, nose, and throat—but there are a few key differences between the two substances.

For one, they’re created from different chemicals. According to biohazard remediation company Aftermath, the active ingredient in pepper spray is oleoresin capsicum, which comes from the compound that makes hot peppers so hot: capsaicin. If you’ve ever accidentally rubbed your eyes after chopping a chili pepper, you’ve gotten a very tiny taste of what it’s like to be sprayed with pepper spray. Tear gas, on the other hand, contains 0-Chlorobenzylidenemalononitrile (CS), 2-chlorobenzalmalononitrile (CN), or a similar artificial chemical. At room temperature, both of those chemicals are powdery solids, not gases—they’re mixed with liquids or gases so they can be dispersed in the air.

Delivery methods differ, too. Pepper spray often comes in an aerosol can, which shoots it in a stream, a mist, or some other relatively direct path (though it’s also available as a gel or foam). As the Berkeley Science Review explains, tear gas is mainly dispersed with a grenade, which releases the substance over a wide area when it explodes. Since the grenades can cover so much ground, law enforcement officers are more likely to use tear gas to try to break up a crowd, and civilians are more likely to carry pepper spray as a personal safety measure.

The immediate effects of the two substances are similar—burning sensation in mucous membranes, rise in blood pressure, difficulty breathing, runny nose, etc.—but tear gas can also cause nausea and vomiting in higher concentrations.

For more on tear gas, including what to do if you’re exposed to it, head here.

[h/t Aftermath]