Hurrah for the plastic brain! At a session this morning on neural prosthetics – smart devices that restore lost nervous system functions – Michael Merzenich of UCSF praised the brain’s remarkable plasticity. Merzenich was describing the way the brain actively cooperates in recovery following a cochlear implant to restore hearing. Despite what Merzenich calls fairly primitive technology, the brain in many cases is able to interpret speech from the limited information it receives.

Neural prosthetic technology is developing fast though. In addition to cochlear implants, researchers are working on retinal implants and new implantable stimulators for bladder control. The latter is particularly important for patients who have had spinal cord injury as loss of bladder control leads to infection and kidney problems. According to William Groat of the University of Pittsburgh, who is developing an implant to stimulate the pudendal nerve, the bladder control pathway is actually a fairly simple system. Imagine, he says, how much harder it gets if you are trying to restore hand or arm function to such patients.

This is exactly what Hunter Peckham of Case Western Reserve University is doing. His team is using multiple-channel implants to restore certain movements to spinal-cord injury patients. As Peckham explains, the act of standing requires activating 8 muscles, walking another 16 or more, while coordination of the stimulation becomes much more complex. An implant for bilateral hand control involves 12 electrodes for stimulating nerves and another two for recording, all of which are connected to a single control device. The amazing recovery of function by many of these patients – allowing one patient to sit erect or to roll over, and yet another to compete as a sailor – is heartening. But as the movements become more complex – and the patients’ expectations become higher – the sheer number of electrodes involved will rise rapidly. What sort of networked implant might be needed to move this amazing research to the next level?

Hurrah for the plastic brain! At a session this morning on neural prosthetics – smart devices that restore lost nervous system functions – Michael Merzenich of UCSF praised the brain’s remarkable plasticity. Merzenich was describing the way the brain actively cooperates in recovery following a cochlear implant to restore hearing. Despite what Merzenich calls fairly primitive technology, the brain in many cases is able to interpret speech from the limited information it receives.

Neural prosthetic technology is developing fast though. In addition to cochlear implants, researchers are working on retinal implants and new implantable stimulators for bladder control. The latter is particularly important for patients who have had spinal cord injury as loss of bladder control leads to infection and kidney problems. According to William Groat of the University of Pittsburgh, who is developing an implant to stimulate the pudendal nerve, the bladder control pathway is actually a fairly simple system. Imagine, he says, how much harder it gets if you are trying to restore hand or arm function to such patients.

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