Learn how to tap into your “gut feeling,” which knows more than you think it does; and why Earth's core is growing lopsided. You do have a "gut feeling" — and it knows more than you think by Cameron Duke Annie Murphy Paul. (2021, July 29). Interoception: how to improve your “gut feeling.” Big Think; Big Think. https://bigthink.com/personal-growth/interoception-how-to-improve-your-gut-feeling Armstrong, K. (2019). Interoception: How We Understand Our Body’s Inner Sensations. APS Observer, 32(8). https://www.psychologicalscience.org/observer/interoception-how-we-understand-our-bodys-inner-sensations Lewicki, P., Czyzewska, M., & Hoffman, H. (1987). Unconscious acquisition of complex procedural knowledge. Journal of Experimental Psychology: Learning, Memory, and Cognition, 13(4), 523–530. https://doi.org/10.1037/0278-7393.13.4.523 Ceunen, E., Vlaeyen, J. W. S., & Van Diest, I. (2016). On the Origin of Interoception. Frontiers in Psychology, 7. https://doi.org/10.3389/fpsyg.2016.00743 Plans, D. (2019, February 5). We’ve Lost Touch with Our Bodies. Scientific American Blog Network. https://blogs.scientificamerican.com/observations/weve-lost-touch-with-our-bodies/ Price, C. J., & Hooven, C. (2018). Interoceptive Awareness Skills for Emotion Regulation: Theory and Approach of Mindful Awareness in Body-Oriented Therapy (MABT). Frontiers in Psychology, 9. https://doi.org/10.3389/fpsyg.2018.00798 Craig, A. D. (2009). How do you feel — now? The anterior insula and human awareness. Nature Reviews Neuroscience, 10(1), 59–70. https://doi.org/10.1038/nrn2555 Earth's core is growing lopsided by Grant Currin Cottier, C. (2021). Earth’s Inner Core Is Growing Lopsided. Discover Magazine; Discover Magazine. https://www.discovermagazine.com/planet-earth/earths-inner-core-is-growing-lopsided Frost, D. A., Lasbleis, M., Chandler, B., & Romanowicz, B. (2021). Dynamic history of the inner core constrained by seismic anisotropy. Nature Geoscience, 14(7), 531–535. https://doi.org/10.1038/s41561-021-00761-w Is Earth’s core lopsided? Strange goings-on in our planet’s interior. (2021, June 3). Phys.org. https://phys.org/news/2021-06-earth-core-lopsided-strange-goings-on.html Ling, T. (2021, June 4). Scientists have measured how Earth’s core grows (and found something really strange). BBC Science Focus Magazine; BBC Science Focus Magazine. https://www.sciencefocus.com/planet-earth/earth-core-asymmetric-growth/ BONUS: Cohen, R. (2020, January 23). The Silurian Hypothesis. The Paris Review. https://www.theparisreview.org/blog/2020/01/23/the-silurian-hypothesis/ Follow Curiosity Daily on your favorite podcast app to learn something new every day withCody Gough andAshley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.
Learn how to tap into your “gut feeling,” which knows more than you think it does; and why Earth's core is growing lopsided.
You do have a "gut feeling" — and it knows more than you think by Cameron Duke
Earth's core is growing lopsided by Grant Currin
Follow Curiosity Daily on your favorite podcast app to learn something new every day with Cody Gough and Ashley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.
Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/earths-core-growing-lopsided-and-the-science-of-gut-feelings
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 scientific explanation for your “gut feeling” — and why it knows more than you think; and why Earth’s core is growing lopsided.
CODY: Let’s satisfy some curiosity.
It might seem like a bad idea to “go with your gut” sometimes. I mean, what does your gut know, anyway? That gut feeling has a scientific name, and according to research, it knows more than you think it does.
In 1992, a neuroscientist ran an experiment where he had participants watch a target disappear and reappear on a screen. They did this over and over again for a few hours. What the participants didn’t know was that the targets were following a predictable pattern — although it was a really complicated one. And after a while, the participants began to accurately predict where the target would appear next. But here’s the thing: they couldn’t explain how they knew. Even when they were offered $100 to identify the pattern, they couldn’t do it.
Pawel Lewicki was the neuroscientist who ran that experiment. And he called the phenomenon “nonconscious information acquisition.” Basically, we have the ability to sense, store, and recall information completely unconsciously.
This phenomenon is governed by something called interoception. That refers to an awareness of the inner state of the body — things like hunger and your heartbeat. Think of it as a sense like sight or smell, but much more subtle. Just like sight and smell involve sensors that pass information to the brain, sensors all over your body pass information to a brain structure called the insula, which is a region embedded within the cerebral cortex.
These sensors might not be giving our conscious minds the kinds of concrete information that our eyes or nose do, but that doesn’t mean the information we are getting isn’t useful — or that it doesn’t affect our conscious decisions.
Further research was able to shed light on exactly how this happens. In one experiment, participants turned over playing cards from four decks. Some cards gave a reward and others came with a penalty. What the players didn’t know is that half of the decks were rigged to take larger penalties than the others. As they played, researchers used electrodes attached to the players’ fingers to monitor their levels of physiological arousal. Soon into the game, the participants began sweating ever so slightly whenever they contemplated playing from the rigged decks. But the players didn’t notice that they were sweating, and they had no idea why they were making the decisions that they were making.
Essentially, their brains were collecting and storing information that the conscious mind wasn’t tracking. Whenever the players were about to make a bad decision in the game, their nervous systems sent out a little warning sign that actually affected their behavior.
Interoception is powerful. Remember that when you’ve got a bad feeling about something, it’s probably not for nothing.
Seismologists have some surprising news: Earth’s inner core is growing... lopsided. The core itself isn’t deformed, thanks to gravity, but the finding still poses a mystery that scientists are trying to solve.
Studying the inner core is not an easy thing to do. The researchers behind this study used data from earthquakes: they can measure the amount of time it takes seismic waves from earthquakes in one part of the world to travel through the planet and reach the other side, and use that data to make some inferences about the stuff the waves had to travel through. They used those numbers in some very precise calculations to figure out what’s been going on at the very center of the Earth.
The study let the scientists estimate the age of the inner core, which they think is between half-a-billion and one-and-a-half billion years old. That means it took at least a couple billion years for the planet to cool down enough for its fully liquid core to differentiate into the outer core, which is still liquid, and the inner core, which is made of crystallized iron and nickel. Earth is still generating some heat through radioactive decay, but a lot of its thermal energy is left over from its initial formation. We’re all living on a very beautiful — and very effective — thermos.
According to data, the inner core puts on a new layer about 1 millimeter thick every year. That’s how long a fingernail grows every ten days! The painstakingly slow growth happens each time a tiny amount of iron or nickel cools down enough to form a crystal.
But here’s the surprise: it isn’t cooling down at the same rate everywhere. Part of the core that’s underneath Indonesia is cooling off a lot faster than other regions. Researchers think about 60 percent more crystals are forming in that part of the core than on the opposite side.
Does that mean Earth is doomed to grow lopsided, wobble off its orbit, and be catapulted out of the Solar System and into deep space!? No. It turns out the core is still a sphere, even after who-knows-how-many hundred-million years of lopsided growth. The researchers say gravity is always shifting matter to maintain a spherical core.
While scientists don’t know what causes the uneven growth, this discovery does solve another mystery: why crystals in the inner core align in a North-South direction, rather than pointing every which way. This alignment means that earthquakes travel faster between the poles than they do across the equator. If the inner core is always redistributing these crystals to maintain its shape, it makes sense that they’d flow in an orderly direction. At least that’s one mystery about the center of the Earth that scientists no longer have to dig for.
Let’s recap today’s takeaways
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ASHLEY: Today’s writers were Cameron Duke and Grant Currin.
CODY: Our managing editor is Ashley Hamer.
ASHLEY: Our producer and audio editor is Cody Gough.
CODY: [AD LIB SOMETHING FUNNY] Join us again tomorrow to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!