Ramaswamy Palaniappan, a computer scientist at the University of Essex, believes that your identity can be revealed by the brain waves that are stimulated when you gaze at a picture. He is one of a handful of researchers toiling away in the field of EEG (electroencephalogram) biometrics; another is Julie Thorpe, at Carleton University in Ottawa, who believes that we will eventually use "passthoughts", rather than passwords, to access our computers.

While people may be tricked into giving up their passwords, smartcards may be lost or stolen, as can biometric templates stored on computers for comparing eye or fingerprint scans, so-called "passthoughts" are unique.

We present a novel idea for user authentication that we call pass-thoughts. Recent advances in Brain-Computer Interface (BCI) technology indicate that there is potential for a new type of human-computer interaction: a user transmitting thoughts directly to a computer. The goal of a pass-thought system would be to extract as much entropy aspossible from a user’s brain signals upon "transmitting" a thought. Provided that these brain signals can be recorded and processed in an accurate and repeatable way, a pass-thought system might provide a quasi two-factor, changeable, authentication method resistant to shoulder-surfing. The potential size of the space of a pass-thought system would seem to be unbounded in theory, although in practice it will be finite due to system constraints. In this paper, we discuss the motivation and potential of pass-thought authentication, the status quo of BCI technology, and outline the design of what we believe to be a currently feasible pass-thought system.