Learn about imaginary beams of motion coming from people’s eyes; where lost luggage ends up; and octopus sleep cycles. Following someone's gaze may involve imagining a beam of motion from their eyes by Grant Currin Our Brains “See” Beams Of Motion Emanating From People’s Faces Towards The Object Of Their Attention. (2021, February 25). Research Digest; Research Digest. https://digest.bps.org.uk/2021/02/25/our-brains-see-beams-of-motion-emanating-from-peoples-faces-towards-the-object-of-their-attention/ Guterstam, A., & Graziano, M. S. A. (2020). Visual motion assists in social cognition. Proceedings of the National Academy of Sciences, 117(50), 32165–32168. https://doi.org/10.1073/pnas.2021325117 Guterstam, A., & Graziano, M. S. A. (2020). Implied motion as a possible mechanism for encoding other people’s attention. Progress in Neurobiology, 190, 101797. https://doi.org/10.1016/j.pneurobio.2020.101797 Guterstam, A., Wilterson, A. I., Wachtell, D., & Graziano, M. S. A. (2020). Other people’s gaze encoded as implied motion in the human brain. Proceedings of the National Academy of Sciences, 117(23), 13162–13167. https://doi.org/10.1073/pnas.2003110117 This Is Where Most of the Lost Luggage in the US Ends Up originally aired May 10, 2018 https://omny.fm/shows/curiosity-daily/everything-repellent-clothing-resonant-breathing-a We finally discovered alternating sleep states in an octopus by Cameron Duke Medeiros, S. L. de S., Paiva, M. M. M. de, Lopes, P. H., Blanco, W., Lima, F. D. de, Oliveira, J. B. C. de, Medeiros, I. G., Sequerra, E. B., Souza, S. de, Leite, T. S., & Ribeiro, S. (2021). Cyclic alternation of quiet and active sleep states in the octopus. IScience, 0(0). https://doi.org/10.1016/j.isci.2021.102223 Schnell, A. (2021, April 1). Sleeping octopuses might experience fleeting dreams – new study. The Conversation. https://theconversation.com/sleeping-octopuses-might-experience-fleeting-dreams-new-study-158237#:~:text=During%20quiet%20sleep%2C%20octopuses%20are Subscribe to Curiosity Daily to learn something new every day with Cody Gough and Ashley Hamer. You can also listen to our podcast as part of your Alexa Flash Briefing; Amazon smart speakers users, click/tap “enable” here: https://www.amazon.com/Curiosity-com-Curiosity-Daily-from/dp/B07CP17DJY
Learn about imaginary beams of motion coming from people’s eyes; where lost luggage ends up; and octopus sleep cycles.
Following someone's gaze may involve imagining a beam of motion from their eyes by Grant Currin
This Is Where Most of the Lost Luggage in the US Ends Up originally aired May 10, 2018 https://omny.fm/shows/curiosity-daily/everything-repellent-clothing-resonant-breathing-a
We finally discovered alternating sleep states in an octopus by Cameron Duke
Subscribe to Curiosity Daily to learn something new every day with Cody Gough and Ashley Hamer. You can also listen to our podcast as part of your Alexa Flash Briefing; Amazon smart speakers users, click/tap “enable” here: https://www.amazon.com/Curiosity-com-Curiosity-Daily-from/dp/B07CP17DJY
Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/octopuses-have-sleep-cycles-too
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 imaginary beams of motion coming from people’s eyes; where most of the lost luggage in the US ends up; and why it’s a big deal that we discovered alternating sleep states in an octopus.
CODY: Let’s satisfy some curiosity.
Do your eyes shoot out invisible beams that scan the world? If you asked a little kid how vision works, they might say “yeah” — or at least, something along those lines. The funny thing is, ancient thinkers like Ptolemy and Galen thought the same thing. And a good number of college students who’d just taken a psychology class also thought something along those lines, at least according to one study.
That’s, you know, kind of the opposite of how it works. But the misconception is so common that some psychologists argue that our brains must be predisposed to thinking that way.
In fact, there’s some evidence that points in that direction. One study found that when people look at an image of someone gazing at an object, they’re slower to recognize subtle movement between the eyes and that object, as if their brains were already visualizing movement in that direction. Another study found that seeing someone gaze at an object activated the same motion areas of the brain as actual motion does. According to that study, quote, “It is as if the brain draws a quick visual sketch with moving arrows to help keep track of who is attending to what.”
And a new study now offers some real-world evidence to back up these claims.
For the study, Princeton researchers had volunteers look at a screen where two goofy cartoon faces were staring at a soccer ball sitting between them. The volunteers had to quickly say which face was paying more attention to the soccer ball. Complicating things slightly was the background, where a ton of tiny dots were moving at random.
The faces were identical, so half the volunteers said the face on the left was paying better attention and the other half said it was the face on the right.
But that was just the beginning. See, the researchers made a few different versions of this little animation. It always looked like the dots were moving randomly, but sometimes the dots were very, very subtly moving in a specific direction — so subtly that the majority of the participants didn’t consciously notice it. And that’s where the results got interesting.
It made no difference at all when the dots were moving from the ball toward one of the faces. But get this: when the dots were moving from one of the faces toward the ball, a majority of participants thought that person was paying closer attention! The difference wasn’t huge, but it stuck out in the stats: a 56/44 split.
Those results suggest that human brains are, in fact, predisposed to imagining sight as something that comes from the eye. Our brains might be using their own visual shorthand to keep track of everyone’s attention — and we don’t even know they’re doing it.
CODY: As more people get the COVID-19 vaccine, more people will be hopping on airplanes. And more people on planes means one thing: more lost luggage. Here’s a story we remastered from 2018 that is nothing if not a curiosity.
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It feels like we learn something mind-blowing about octopuses pretty much every week. The closer scientists look at them, the more they realize that certain traits we think of as uniquely human — or at least uniquely mammalian — aren’t actually that unique. Now we can put one more on the list: a new study has confirmed the first-ever observation of distinct sleep cycles in octopuses.
In a recent experiment, a team led by Sylvia Medeiros, a researcher at a University in Brazil, watched four octopuses while they slept. They recorded their sleep and paid careful attention to their bodies as they snoozed. To make sure the octopuses were actually sleeping, the team would check the octopus’ arousal levels by showing it an image of a crab or by thumping on the glass. During these observations, the researchers saw what seemed to be two distinct stages of sleep. One, which the researchers dubbed "quiet sleep," kind of looks like what you’d expect a sleeping octopus looks like. It stayed very still with its eyes narrowed to slits, and its skin was pale. But after about 40 minutes of quiet sleep, the octopus would transition to "active sleep." During active sleep, the octopus’ skin began changing color and the animal began shifting around, swaying back and forth and moving its arms a little. It had an uncanny similarity to our own REM sleep, which is the sleep stage when we dream.
All animals are known to sleep at some level. However, only animals on our branch of the evolutionary tree are known to have distinct sleep stages. Well, until now. Octopuses are distantly related enough to humans to rule out the possibility of inheriting this particular brand of sleep from a common ancestor. They must have evolved it independently.
This further deepens the mystery of the evolution of sleep. It’s obviously important enough to be maintained from our ancestors, but the fact that it could evolve independently means there must be something crucial about it.
Now, this doesn’t mean that octopuses can dream. In fact, we don’t have any direct evidence that non-human animals actually dream. We might be convinced that our dogs are chasing dream rabbits, but confirming this is very difficult. The same goes for octopus dreams.
But if they do dream, I wonder what they dream about?
Let’s recap today’s takeaways
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ASHLEY: Today’s writers were Grant Currin and Cameron Duke.
CODY: Our managing editor is Ashley Hamer.
ASHLEY: Our producer and audio editor is Cody Gough.
CODY: Fulfill your wildest dreams by join us again tomorrow to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!