“EVEN the most sophisticated electronic security can be defeated by forcing someone to reveal a password. But what if sensitive information could be stored in your brain in such a way that you couldn’t consciously disclose it, no matter how hard you tried? That is the promise of a new technique that combines cryptography with neuroscience. In initial tests, volunteers learned a password and later used that password to pass a test, but could not identify it when asked to do so. The system is based on implicit learning, a process by which people can unconsciously learn a pattern. Hristo Bojinov, at Stanford University in California and colleagues designed a game in which players intercept falling objects by pressing a key. The objects appear in one of six positions, each corresponding to a different key.”