john krakauer of what you hope to do with stroke. why don't you outline what you are thinking about that. >> well, right so i think what follows then, i see, because the very same plasticity in these extreme cases where you are disconnected, where are you going to have to bypass the severed pathways and control an external device with this plas 'tis at this time, in patients who have stroke, for example where they still have some residual movement left, the question you want to ask is a similar one. can you somehow augment their plasticity in sort of enhance their recovery. and so there are a number of points to make about that. most patients after injury which are less extreme than what we just saw, recover to some degree and they recover most of the time within the first few months after stroke. but not completely. and we know from animal models that this seems to be a time window of plasticity that finishes after about three months in humans. about four weeks in ro dent models. so what we want to do is can we use technology to try