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Humans judge each other within 33 milliseconds of seeing each other! We learn better if we think we have to teach someone else, and video games are good for us!

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Hosted by: Hank Green
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Hello! I'm Hank Green, and this week on SciShow News, we're talking about you, or at least about us. Humans, and some of the weird things our brains do: how we're bad at judging people, bad at studying, and that video games might actually be good for kids - in moderation of course.


 We're Bad Judges (0:28)

Let's start out with our complete inability to stop basing our opinion of people on the way that they look. This prejudice isn't always something that's learned, and it's something very hard to fight against, with our brains making snap judgments about people in, apparently, 33 milliseconds after seeing a face. That's faster than it takes us to even be aware that we have been shown a face.

This, according to a study from NYU's Jonathan Freeman who says that the results are, quote, "consistent with an extensive body of research suggesting that we form spontaneous judgments of other people that can be largely outside awareness". The study focused on the perception of trustworthiness and the roll of the amygdala, a part of the brain important in decision-making and emotional reactions.

They monitored activity in the amygdala while showing subjects a range of faces, some of them with high cheekbones and eyebrows, which people judge as trustworthy, and others with low, furrowed brows and low cheekbones which have been rated by a large body of research as untrustworthy. Some of the faces were real people; others were computer generated.

The amygdala of the test subjects responded the same whether the subject were allowed to perceive the image for a prolonged period of time, or for mere milliseconds - too quick to even be consciously perceived. So, yeah, when we say that humans make "flash judgments" we're not being hyperbolic.

And if you're wondering, there is no evidence that people who look untrustworthy or trustworthy actually are. So yeah, we're just bad at that.

 Learning for Teaching (1:50)

What else are you bad at? Studying, probably. If you want to get better at it, you might just have to think about it differently.

According to research from Washington University in St. Louis, people learn significantly more effectively when they're told to prepare to teach someone the material than if they're just told that they'll be tested on the material, even when they're given the same amount of time with the material. This suggests that when digesting material, thinking about how you will present it to another person is a better framework than thinking about how you're going to store it in your own brain.

This is especially important for getting the main points of the material. Testing on details showed less difference between those expecting to teach versus those expecting to test. On main points, however, learners expecting to teach scored 25 to 50 percent higher. So, apparently, if you want to learn, just think about how to teach.

 Minecraft is Good! (2:36)

And finally, video games are good for kids! And by extension, let's just assume, for everyone and just, like, stop watching SciShow and go play Minecraft. That's what I'm going to do, 'cause...

According to a new study in the journal Pediatrics, which surveyed a large group of ten to fifteen-year-old children on their time spent gaming and their level of psycho-social adjustment: children who spent more than 3 hours per day playing video games were found to rank lower in life satisfaction, pro-social behavior, and dealing with problems than all other groups, while those who gamed for less than an hour a day were found to have the highest rankings of all the groups, including those who didn't game at all.

It's worth remembering, of course, that none of the differences here were gigantic. The variance between all of the sets was only 1.6 percent.

Also, it isn't necessarily the video games causing the difference. It seems possible, for example, that kids who have access to video games but have the self control or family structures necessary to limit play might be more likely to be psycho-socially well adjusted.

 Closing (3:34)

Thanks for watching this psychology-based episode of SciShow News. Over on SciShow Space this week we'll be talking about the end of a space probe's ten year journey to rendezvous and orbit with a comet, and some surprising observation of Jupiter's moon, Io, and our moon... the Moon.

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