Learn about the first physical evidence that shows how our brains store short-term memory; EndeavorRx, the first ever prescription video game; and why hummingbirds can see colors that you can’t.
Learn about the first physical evidence that shows how our brains store short-term memory; EndeavorRx, the first ever prescription video game; and why hummingbirds can see colors that you can’t.
Scientists may have found how short term memory is physically stored by Andrea Michelson
The first prescription video game ever was just approved by the FDA by Grant Currin
Hummingbirds can see even more colors than we thought by Grant Currin
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Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/the-first-prescription-video-game-solving-the-mystery-of-short-term-memory-and-hummingbirds-extraordinary-vision
CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from curiosity-dot-com. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, you’ll learn about the first physical evidence that shows how our brains store short-term memory; the first ever prescription video game; and why hummingbirds can see colors that you can’t.
CODY: Let’s satisfy some curiosity.
When you remember a name or a phone number, how is it stored in your brain? Like, is it just a nebulous mix of chemical signals, or is there an actual physical trace of a memory in there? Well, scientists just devised an amazing method to answer that question, and they say it’s the latter. Scientists may have actually discovered the physical representation of short-term memory.
To better understand how memories are stored in our own brains, researchers at the Institute of Science and Technology Austria took a close look at neurons (or brain cells) in mice. They focused on the hippocampus, where both humans and mice store memories, and zoomed in on a single point of connection between two neurons. That point is called a synapse, and it’s where messages are sent from one neuron to another. Those messages come in the form of chemicals called neurotransmitters, which travel in little bubbles called vesicles.
The scientists accomplished something that study author David Vandael [van-DELL, I think] called “close to impossible”: they recorded electrical signals from the sending neuron and receiving neuron at the same time while the mouse completed memory-stimulating tasks. They found that when a neuron fires off a signal, the connection between that neuron and the one receiving the signal strengthens temporarily. That’s called synaptic plasticity, and they expected it to happen. But how it happened was pretty surprising.
It turns out that the connection is made stronger not by an increase in the amount of neurotransmitters in the synapse, but by an increase in the neurotransmitters that have yet to be released. Before they’re sent across the synapse, vesicles full of neurotransmitters gather on the sending neuron. And during those moments when the signal was strengthened, Vandael and his colleagues noticed that there were more vesicles on deck. More vesicles means more neurotransmitters are ready to be released when the time is right.
The vesicles can sit there for a few minutes at a time, and they’ll stay for longer if there’s not too much other activity going on. Starting to sound familiar? Vandael thinks these vesicles might be a physical representation of short-term memory. The idea that there may be physical traces of memory called “engrams” has been around since the early 20th century, but we’ve never seen physical evidence for them. This may be the mythical engram. And the phone number you remembered? It may be there in bubbles of neurotransmitters waiting to be released.
The FDA recently announced some big news for kids with ADHD and the people who love them: their next treatment might involve a video game. That’s right! After years of testing, a company in Arizona has won approval to market a video game to help treat kids from 8 to 12 years old who struggle with ADHD. It’s called EndeavorRx, and it’s the first video game-based therapy the FDA has ever authorized.
Now, EndeavorRx isn’t a cure for ADHD or even a standalone therapy. But seven years of clinical trials that involved about 600 kids convinced the FDA that the game can be a useful part of a therapeutic regimen — a regimen that may include other forms of clinical therapies, medication, and educational programs.
To win approval, the game’s developer had to show the FDA that the game-based treatment is safe and effective. In one of the five studies they presented as evidence — which, I should point out, were funded by the game company — 348 kids with ADHD spent four weeks playing one of two games: EndeavorRx, or a spelling game that wasn’t designed to treat ADHD. Each participant played for 25 minutes per day, five days a week. Their symptoms were measured before the month of gameplay and then again afterward.
The results weren’t spectacular, but they were encouraging — and convincing enough to get government approval. After those four weeks, about 30 percent of kids who played EndeavorRX showed no sign of an attention deficit in at least one of the ways the researchers used to measure it. The improvement lasted for up to a month after the treatment. That wasn’t true of the control group.
What’s this prescription video game like? It’s played on an iPhone or iPad, and the user’s job is to fly around fantastical landscapes and avoid obstacles while collecting alien-looking targets. They’re guided by aliens who cruise on flying saucers. It’s designed to stress the user’s ability to pay attention to multiple things at once, according to the developer.
The FDA created a new regulatory classification to approve the game. That means similar treatments can be approved more easily in the future. Maybe one day, video games will become a regular part of a mental health treatment regimen. Better practice now, just in case.
Is there anything nicer than walking through a field of wildflowers? A new study says yes: flying through the same field, with the eyes of a hummingbird. Their ability to see ultraviolet light gives hummingbirds access to a super-chromatic wonderland mostly invisible to us humans.
The closest we can get to imagining what hummingbirds see is to think about purple. Why? Because purple is a nonspectral color. You can’t make it with monochromatic light. In other words, it’s not in the rainbow. This is weird, but stay with me: our brains create purple when our eyes detect light with short wavelengths — like blue and violet — and light with long wavelengths — like red — at the same time. Instead of splitting the difference and showing us medium-wavelength light — you know it as green — our brains create something different: purple. It’s the only nonspectral color humans can see because our eyes can only have three kinds of light-detecting cells. One for light with long wavelengths, another for medium, and a third for short.
CODY: So you’re saying the color purple literally doesn’t exist? [answer]
ASHLEY: Hummingbirds have four kinds of light-detecting cells: those same three plus one for light with supershort wavelengths, also known as ultraviolet light. That means they can see five nonspectral colors: purple, also known as violet plus red; along with ultraviolet-plus-red, ultraviolet-plus-yellow, ultraviolet-plus-green, and ultraviolet-plus-purple. At least in theory.
To find out whether hummingbirds could actually see all those nonspectral colors, the researchers behind the recent study set up some LED tubes and sugarwater. The LED tubes let them make nonspectral colors, like ultraviolet plus red. And the sugarwater let them train wild hummingbirds to associate a particular nonspectral color with the nectar-like reward. Over the course of 19 experiments, hummingbirds consistently showed that they could detect color differences that humans can’t see at all. In one experiment they distinguished between green and a mixture of ultraviolet plus green. In another, they could tell the difference between two mixtures of ultraviolet plus red: one that had more ultraviolet and one that had more red.
What do these combinations look like? Unfortunately, the researchers and humans in general have absolutely no idea. But they do know hummingbirds probably aren’t the only species that can see them. Most birds and a lot of fish and reptiles have those same four light-detecting cells. And there’s a very good chance that dinosaurs did, too. When it comes to being able to see these wild colors, humans may be the odd ones out.
CODY: Let’s recap the main things we learned today. Starting with
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CODY: Today’s stories were written by Andrea Michelson and Grant Currin, and edited by Ashley Hamer, who’s the managing editor for Curiosity Daily.
ASHLEY: Today’s episode was produced and edited by Cody Gough.
CODY: Join us again tomorrow to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!