A Horse Can't Tell What a Jacket Is — but It Never Forgets What It Learned Ten Years Ago

Picture a horse named True. He's four or five years old, wandering around a ranch in Minnesota with his owner, when he spots something new in the distance: a stack of steel fence panels, about 10 feet long and 5 feet high, piled up like giant metal Jenga blocks. True stops, sizes them up, gets curious, and basically asks with his whole body: what is that? Then he moves on. No big deal.

The next day, same ranch, same fence panels — except this time they're approaching from a different direction. The moment True's owner steps out of the barn, he snorts. Not a little snort. He "blew, actually" — and according to the scientist standing next to him, a horse's blow is loud enough "to break eardrums." He's more scared than he was the day before, even though he'd already seen these exact panels less than 24 hours earlier.

That doesn't sound like an animal with a good memory. It sounds like the opposite. But here's the twist: this same horse can remember something completely useless for ten years straight — better than you probably remember your own locker combination from last year. To understand why, you have to meet the woman who owns him, and rethink everything you assume a "smart" brain looks like.

Her name is Janet Jones. She's a neuroscientist who has ridden horses since she was a kid, and she just wrote a book called A Horse's World. True — full name True North — is her own horse, a Dutch Warmblood with a diamond-shaped white patch on his forehead that reminded her of the North Star, which is how he got his name. She sat down with Short Wave host Emily Kwong, who — born, by her own account, in the Chinese zodiac year of the horse — admits she's "a bit obsessed" with them. You can hear it in how the whole conversation crackles with real excitement, not textbook seriousness.

Your Brain Has a Skip-the-Line Pass. Horses Don't.

Try this experiment in your head. Your friend puts on "an oversized thing with a zipper down the front." Your brain doesn't pause to investigate — it fires off one word instantly: jacket. And once something's filed under "jacket," it stays filed. Even if that jacket ends up crumpled on the floor, your brain doesn't treat it as a strange new object. It's already been cleared. Safe.

Quick decode: scientists call this shortcut categorical perception — your brain's way of sorting the world into bins so it doesn't have to fully re-investigate every familiar-looking thing from scratch, every single time.

Horses barely have this shortcut. Jones's explanation is blunt: horses are prey animals, so anything that hasn't been fully checked out could be a threat — they can't afford to assume "I saw that yesterday, so it's fine." Humans aren't prey, so we don't need to be that paranoid. That's why True's brain, faced with the exact same pile of fence panels on day two, basically ran the entire danger-assessment process over again from zero. It also explains a headache horse trainers know all too well: a horse can learn a bad habit in exactly one try — a single accidental mistake can get locked in as a permanent lesson.

But Its Memory Might Put Yours to Shame

Here's the first jaw-dropping fact. In one study — the episode doesn't name the researchers or the university, so that's all the detail there is — horses were taught a rule for telling different geometric shapes apart. Once the experiment ended, those horses never touched the rule or saw those shapes again.

Ten years later, researchers brought one of the horses back and tested it. On the original shapes: 100% accuracy. On brand-new shapes it had never seen, applying that same old rule: accuracy barely dipped, to 98%.

Now compare that to us. By Jones's account (she doesn't name a source for this either), a human who learns a rule and never uses it again remembers about 50% of it after just one hour. After 24 hours, that's down to 30%. After a week, an "embarrassing" 10%. Horses, meanwhile, hang on to totally useless information for a minimum of ten years. When Kwong heard the numbers, she blurted out, "They're like elephants" — a fun comparison, but just something she said in the moment, not a data point from the episode itself. Take it as color, not science.

355 Trillion Faces, and Nobody Really Knows What's Behind Them

Second jaw-dropper: according to Jones's book, horses may be capable of more than 355 trillion distinct facial expressions. Most people look at a horse's long face and big eyes and assume: not much going on in there, expression-wise. That number blows the assumption apart, hinting that horses might feel a far richer range of emotions than they've ever gotten credit for.

But Jones doesn't run with that. She hits the brakes immediately, stressing that whatever horses actually feel is likely nothing like what humans feel, and that the research simply isn't far enough along to say much more than that. A number that huge is exciting enough on its own — and a scientist willing to follow it up with "honestly, we don't know yet" is worth remembering just as much as the 355 trillion itself.

(Side note: if a horse's mind already sounds stranger than you expected, Short Wave has an earlier episode about octopus cognition — and what it might tell us about alien life. Horses were surprising enough. Octopuses might be even weirder.)

Riders and Horses: the Only Predator-and-Prey Pair That Shares a Nervous System

Third jaw-dropper, and the strangest one in the whole episode: Jones says humans and horses are the only known pair of species that share neural activity across two separate brains, in real time.

The mechanism turns out to be almost embarrassingly simple. A rider presses the calf of her left leg into the horse's side. The horse's skin receptors pick that up and send the signal up the spine into the horse's brain. The horse moves in response — and the rider's own skin receptors instantly catch that motion and relay it back up to her brain. Press, move, feel, repeat: it's like an invisible phone line strung between two bodies, running nonstop through dressage, showjumping, and racing — mostly without either horse or rider ever noticing it's there.

Here's what makes it genuinely strange: horses are prey animals; humans, evolutionarily speaking, are closer to predators. That's not exactly a pairing built on trust. And yet it's precisely this predator-prey combination that pulls off a level of neural syncing no other pair of species is known to reach. Jones is specific about it: as far as anyone knows, it's the only prey-and-predator pair that manages this.

So Was That Fence-Spooked Horse Actually... Smart?

Back to True. He didn't have a bad memory — this is an animal that can hang onto a totally pointless shape-sorting rule for ten straight years. He just doesn't have the shortcut sitting in your brain. Every time, he has to honestly re-evaluate the world from scratch — even if that means getting spooked twice by the exact same stack of metal panels.

And that shortcut in your head? Convenient, sure. But not free. Jones doesn't soften this part: human categorical perception "does create a proclivity toward stereotypes and prejudices" — our brains lump every person in a group together without asking permission, often without us even noticing it's happening. It's a bias you have to catch and correct on purpose. Horses, precisely because they lack that automatic sorting system, can't take that shortcut with people either — left untrained, a horse meets every single person as an individual, no group assumptions attached.

It's a wiring that makes a horse's life more exhausting — and, in its own way, fairer. It can't take shortcuts in judging the world. Human brains, so good at taking shortcuts that we barely notice we're doing it, have to work a little harder to pry those automatic labels back open and look again. Next time your brain slaps a label on someone or something in half a second flat, think of True. He doesn't get that shortcut. Every single time, he actually has to look.