Stanford engineer discovers neural cells that “plan” movement of body parts.Reaching out to touch a dot on a computer screen may seem simple, but it requires a complex chain of signals that link together the eye, brain and arm. Damage to any part of that chain, such as a spinal injury, stroke or neurodegenerative disease, can make even the simplest tasks impossible.

Stanford engineer Krishna Shenoy and a group of researchers at Caltech have shown that at least some links in that chain can be dramatically bypassed. The study is a significant advance in the growing field of neural prosthetics.

The advantage of using planning cells is that they encode a simpler set of parameters than motor cells do. Whereas motor cells generate complex signals that control the three-dimensional path of an arm as it moves toward its target, planning cells encode primarily two parameters: where and when to move.

Systems based on planning cells may be able to use fewer brain cells, and thus simpler electronics, than those based on motor cells.