Yeah, I remember reading about that on Slashdot years ago. That must have been nearly ten years ago.

That is true. I offer interventions to my patients that I would never choose myself. But it is hard to predict what I would choose if I were in their shoes. (Or hospital gowns, rather.)

I doubt this technology will work in the spinal cord. Getting nerves to grow in the peripheral nervous system is pretty easy - they do it on their own. Damaged peripheral nerve axons regrow at a rate of about 1 mm/day, so if you damage a nerve in your armpit it will take weeks to regrow all the way down to your fingertips. Getting nerves to grow in the central nervous system (brain + spinal cord) is tricky. The molecular signaling in the central nervous system actively inhibits regrowth of damaged nerve axons, but we are learning how to experimentally manipulate that signaling to allow some axons to regrow after injury. Someday we hope to therapeutically manipulate that signaling, to help patients with spinal cord injuries, multiple sclerosis, etc.

The nervous system is hugely complex, as you suggested. It is incomprehensibly complex. It is absolutely, beautifully complex. That's why I love it so much.

I am a doctor. In fact, I am a neurologist (IAAN). This article is fascinating, and I hope they keep working on this technology and get it working. That being said, I would never plug one of these things into my own amputated limb. Going to medical school and doing residency have turned me into something of a Luddite. Medical technology is cool, but every treatment has potential benefits and toxicities. The adverse event I would worry about most with this technology is neuropathic pain. Neuropathic pain is notoriously difficult to treat. What if you plugged this device into some amputee's limb and gave them excruciating pain? I would rather have a metal hook for a hand.