Despite these limitations, scientists continue to move BCIs forward. Pomerleau, for example, is working with researchers from the University of Pittsburgh and Carnegie Mellon University on a project known as NeuroSys.

For this group, efforts to turn thought into computing action began with observations of people's brains using a functional magnetic resonance imaging (fMRI) machine. Subjects were told to think about specific words like "search" or "dog," and the machine created an image of the neural activity, lighting up the areas of the brain that were creating the thought.

Working with many test subjects (English speakers only for now), the NeuroSys researchers started with nouns and moved on to verbs, amassing brain scans and noting similarities among them until clear patterns emerged. All this data has been incorporated into a computer program that can translate neural activity patterns to words.

The program has built up a vocabulary of 1,000 words and can parse simple sentences from subjects' brain patterns. Of course, the project needs to deal with the frustrating nuances and ambiguities of language, but it's been surprisingly successful. So far, the program is 90% accurate in predicting what subjects are thinking, according to Pomerleau.

The problem is that there are few computer users who have the desire, or the financial wherewithal, to sit in a $2 million brain scanner to compose a memo to the boss about a new marketing campaign. "A big leap is needed in the sensing technology, to a point where it can be miniaturized," says Pomerleau.