Your social brain is porous — beliefs leak in from the people around you, and once inside, they don't leave just because someone proves them wrong. This lesson focuses on one mechanism in that catalog, and it might be the most unsettling: the continued-influence effect. The short version is that false information keeps influencing your reasoning even after you've been told, understood, and accepted that it was false. Not because you're gullible. Because of how your brain is built.

Ullrich Ecker (b. 1978, Germany / Australia) — a cognitive psychologist who studies misinformation at the University of Western Australia — has run dozens of experiments on this. The setup is always some version of the same thing: give people a story with a false detail, later correct it clearly, then test their reasoning. The correction reduces reliance on the false information. It almost never eliminates it. People keep using the misinformation to fill in gaps, draw inferences, and make sense of events — even when they can correctly tell you the misinformation was wrong.

That experiment is almost exactly what Ecker and his colleagues ran. Participants read a story about a warehouse fire. One version mentioned flammable materials at the scene. Then they were told: actually, there were no flammable materials. When asked open-ended questions about the fire — why it spread, how dangerous it was — people who'd read the original false detail kept referencing it, even after correction, far more than people who'd never read it at all. The correction left a gap where a story used to be. The brain, which hates gaps, filled it with what it already had. This is the mechanism: your mind doesn't store information like a file you can delete. It stores it like a thread in a web. Pull the thread and the web doesn't disappear — it just sags in that spot, and the surrounding threads pull inward to compensate.

This is why the most effective corrections aren't just 'that was false.' They're 'that was false, and here's what actually happened.' Ecker's research consistently shows that corrections with an alternative explanation reduce continued influence far more than corrections that simply deny. Your brain needs something to hold onto. Give it nothing and it reaches for what it already has. The Iraq WMD belief persisted partly because the correction — 'we were wrong, there were none' — left the entire narrative of the invasion without a coherent anchor. No replacement story. So the original one kept filling the space, even in people who intellectually knew it was false. Knowing and reasoning are not the same process. The continued-influence effect is what happens in the gap between them.