Brain surgeons at Boston University have enabled a mute man to speak again by implanting an electrode into his brain. The electrode senses when he's thinking about vowels and reproduces them using a speech synthesizer.
The man first lost his ability to speak after head trauma caused extensive bleeding into the pons area of his brain stem. BU researchers loaded him into a fMRI machine and asked him to attempt to produce specific vowels. After determining that his brain still worked regularly, they implanted an electrode directly onto its speech production parts.
The electrode itself is a marvel of science, containing neurotrophic factors which allow tissue to grown into and around it. While it sounds kind of gross, this stabilizes the electrode and allows it to reside long-term in the brain. It can only sense vowels right now, but the BU team is hoping that this type of technology will let mutes produce words directly in five years or so. [The Future of Things]