Science ·
Brain Rot, a History: From Walden to the Word of the Year
Thoreau coined it in 1854. Oxford crowned it in 2024. Here is what the science says about brain rot, and what it can’t say yet.
In 1854, Henry David Thoreau ended Walden with a complaint. England was working hard to cure the potato rot, he wrote. Would anyone “endeavor to cure the brain-rot, which prevails so much more widely and fatally?”
That is the first recorded use of the phrase, according to Oxford University Press. Thoreau’s target, in Oxford’s summary, was a culture that would “devalue complex ideas” in favor of simple ones. He thought that habit was spreading faster than any crop disease.
170 years later, Oxford made it official
On December 2, 2024, Oxford named brain rot its Word of the Year. More than 37,000 people voted. Oxford’s definition: “the supposed deterioration of a person’s mental or intellectual state,” especially from too much trivial or unchallenging material, now mostly online.
Use of the term rose 230% between 2023 and 2024. The people driving that rise were the ones supposedly rotting. Casper Grathwohl, president of Oxford Languages, pointed out that the phrase spread through social media, “the very place said to cause ‘brain rot’,” and read it as “a somewhat cheeky self-awareness” in younger generations.
That self-awareness matters. Nobody calls their own habit brain rot unless part of them is still paying attention.
The dictionaries kept going. In 2025, Dictionary.com picked 67, a word its own editors called impossible to define. You can read our entry for brain rot in the lexicon.
What the science says
The biggest study so far came out in 2025 in Psychological Bulletin, a journal of the American Psychological Association. A team led by Lan Nguyen at Griffith University pooled 71 studies covering about 98,000 people, as PsyPost reported.
The pattern was clear. People who watch more short-form video, the TikTok, Reels, and Shorts kind, tend to score worse on tests of attention and inhibitory control, which is the skill of stopping yourself from doing the next easy thing. The link was moderate. Heavier use also came with more anxiety, stress, and depression, though that link was small.
One result broke the pattern. The review found no significant overall link between short-form video and body image or self-esteem, which suggests that what people watch matters more than the format.
What it can’t say yet
Most of those 71 studies were cross-sectional. They measured people once, at one moment. That design can show two things travel together. It can’t show which one causes the other.
PsyPost spelled out the obvious alternative: people who already struggle with attention or anxiety may be the ones who reach for the endless feed. The study can’t rule that out. So when someone tells you short videos rot your brain, the honest answer is that heavy users do worse on attention tests, and nobody has yet proven the videos did it.
The genre that named itself
Then came Italian brainrot. In early 2025, TikTok filled with AI-generated creatures: a shark in sneakers, a crocodile fused to a bomber, a ballerina with a cappuccino for a head. Each one got a nonsense Italian name, read aloud by a text-to-speech voice.
The first widely cited character was Tralalero Tralala, posted in January 2025, according to Wikipedia. Who made it is disputed. Several accounts get credit, and Wikipedia says the exact origin is unclear.
The genre wears the insult as a name. It is brain rot on purpose, and everyone watching is in on the joke.
Why we built a field guide
Thoreau asked who would cure the brain-rot. We think the cure starts with the same curiosity that keeps people scrolling, pointed somewhere useful.
So every creature in our field guide is a way into something real. The shark in sneakers comes with shark biology and the history of the shoe. Every word in the lexicon comes with where it actually came from. And every specimen links to a free 3D print, because the fastest way to stop consuming something is to make it.
Around here, brain rot is where the learning starts.
Sources
- Oxford University Press, “‘Brain rot’ named Oxford Word of the Year 2024”, December 2, 2024.
- Dictionary.com, “Word of the Year 2025”.
- Nguyen, L., et al., “Feeds, feelings, and focus: A systematic review and meta-analysis examining the cognitive and mental health correlates of short-form video use,” Psychological Bulletin, 2025. PubMed record.
- PsyPost, “Large meta-analysis links TikTok and Instagram Reels to poorer cognitive and mental health”.
- Wikipedia, “Italian brainrot”.