the_newsbeagle writes: Yesterday, Facebook announced that it's working on a "typing by brain" project, promising a non-invasive technology that can decode signals from the brain's speech center and translate them directly to text (see the video beginning at 1:18:00). What's more, Facebook exec Regina Dugan said, the technology will achieve a typing rate of 100 words per minute. Here, a few neuroscientists are asked: Is such a thing remotely feasible? One neuroscientist points out that his team set the current speed record for brain-typing earlier this year: They enabled a paralyzed man to type 8 words per minute, and that was using an invasive brain implant that could get high-fidelity signals from neurons. To date, all non-invasive methods that read brain signals through the scalp and skull have performed much worse. Thomas Naselaris, an assistant professor at the Medical University of South Carolina, says, "Our understanding of the way the words and their phonological and semantic attributes are encoded in brain activity is actually pretty good currently, but much of this understanding has been enabled by fMRI, which is noninvasive but very slow and not at all portable," he said. "So I think that the bottleneck will be the [optical] imaging technology," which is what Facebook's gear will be using.