Remarkable. Here's what seems to be the key point (reordered a bit for clarity):
The study supported our hypothesis [...] that the premotor cortex represents intended speech as an 'auditory trajectory,' that is, as a set of key frequencies (formant frequencies) that vary with time in the acoustic signal we hear as speech. [...] In an intact brain, these frequency trajectories are sent to the primary motor cortex where they are transformed into motor commands to the speech articulators. [...We] had to interpret these frequency trajectories in order to translate them into speech. [...] In other words, we could predict the intended sound directly from neural activity in the premotor cortex, rather than try to predict the positions of all the speech articulators individually and then try to reconstruct the intended sound [...]
Also remarkable (but maybe this is old hat to people who know about this stuff?) is that the signals they're interpreting come from neurites that started actually growing into the electrode months after it had been implanted.
I suppose there is a big difference between being able to interpret pre-speech frequencies in a normal brain (i.e. of a person who hasn't used this device before), versus someone being able to train themselves to communicate using this device over time. Given how adaptable the brain is, it's the latter that would seem to be the big win (and the article does vaguely imply this). Of course the device presumably wouldn't work at all if it weren't rooted in normal speech function.
The study supported our hypothesis [...] that the premotor cortex represents intended speech as an 'auditory trajectory,' that is, as a set of key frequencies (formant frequencies) that vary with time in the acoustic signal we hear as speech. [...] In an intact brain, these frequency trajectories are sent to the primary motor cortex where they are transformed into motor commands to the speech articulators. [...We] had to interpret these frequency trajectories in order to translate them into speech. [...] In other words, we could predict the intended sound directly from neural activity in the premotor cortex, rather than try to predict the positions of all the speech articulators individually and then try to reconstruct the intended sound [...]
Also remarkable (but maybe this is old hat to people who know about this stuff?) is that the signals they're interpreting come from neurites that started actually growing into the electrode months after it had been implanted.
I suppose there is a big difference between being able to interpret pre-speech frequencies in a normal brain (i.e. of a person who hasn't used this device before), versus someone being able to train themselves to communicate using this device over time. Given how adaptable the brain is, it's the latter that would seem to be the big win (and the article does vaguely imply this). Of course the device presumably wouldn't work at all if it weren't rooted in normal speech function.