Update from Elon Musk & Neuralink regarding threads coming loose in their N1 implant:
In a video posted to X today, Neuralink’s leadership discuss updates, including how they are adapting their approach after unanticipated device malfunction in which implanted threads came loose (link to my summary at the bottom)
“Another of the risk mitigations that we’re looking at in the future is that the implant has a certain size, the depth of the bottom of the implant is actually thinner than the average skull. So what we want to be able to do is control the size of the gap under the implant to give the threads that travel from the implant into the brain as much slack as possible. We didn’t do this in the first participant because we didn’t want to manipulate any of their tissue that we didn’t absolutely have to.” - Matthew MacDougall, Head of Surgery
“In upcoming implants, our plan is to sculpt the surface of the skull, very intentionally, to minimize the gap under the implant, such that the bottom of the implant travels perfectly flush with the normal contour of the inner side of the skull. That will put the implant closer to the brain, will eliminate some of the tension on the threads and we think it will reduce some of the tendency of the threads to retract from the brain.” - Matthew MacDougall
“This is actually a very important detail. You want the inner contour of the brain to be flush, so the brain doesn’t want to “pucker up into the gap. That’s really quite a big deal.” - Elon Musk
“You may think the most obvious mitigation for threads that pulled out of the brain is to insert them deeper. We think so too. So we’re going to broaden the range of depth to which we insert threads…now that we know retraction is a possibility, we’re going to insert at a variety of depths that even in several cases of different amounts of retracting threads we’re going to have electrodes at the proper depth, and with the deepest threads, be able to track how much retraction has occurred across the surface of the brain from each thread.” - Matthew MacDougall
My summary of Neuralink’s thread retraction issues:
