'Tem merda na cabeça' is a piece of Brazilian internet slang that travelled as a shareable voice meme, passed around in group chats and meme pages as a jokey way to call someone clueless. Like the Emotional Damage meme, it thrives as a reaction clip: short, quotable and instantly understood by anyone in on the joke. Its exact original video is hard to pin down, which is typical of WhatsApp-era meme audio, but the phrase keeps resurfacing in edits, streams and comment sections wherever Portuguese-speaking communities gather online.