You should always watch what you say, but now you might have to watch what you think.
Scientists at UC Berkeley can now decode what a person is thinking based on the words they hear, after an experiment was conducted on 15 patients who were already receiving treatment for intractable epilepsy and volunteered.
The Guardian reports the scientists removed a portion of the patients' skulls and laid electrodes on their brains.
More on the actual science from the Guardian:
"The brain seems to break sounds down into their constituent acoustic frequencies. The most important range for speech is 1-8,000 Hertz.
Pasley compared the technique to a pianist who can hear a piece in their mind just by knowing which keys are played.
He next played a collection of new words to the patients to see if the algorithms could pick out and repeat recognisable words. Among them were words such as "Waldo", "structure", "doubt" and "property".
The scientists got their best results when they recorded activity in the superior temporal gyrus, part of the brain that sits to one side, above the ear."
The technology is in its infancy, but researchers believe someday prosthetics could be implanted in to people's brains to help them speak. It could be groundbreaking for those who can't speak on their own, but if this technology gets in the wrong hands, the implications could be as spooky as they are amazing.