Direct cortical control of 3d neuroprosthetic devices

摘要

Control signals for an object are developed from the neuron-originating electrical impulses detected by arrays of electrodes chronically implanted in a subject's cerebral cortex at the pre-motor and motor locations known to have association with arm movements. Taking as an input the firing rate of the sensed neurons or neuron groupings that affect a particular electrode, a coadaptive algorithm is used. In a closed-loop environment, where the animal subject can view its results, weighting factors in the algorithm are modified over a series of tests to emphasize cortical electrical impulses that result in movement of the object as desired. At the same time, the animal subject learns and modifies its cortical electrical activity to achieve movement of the object as desired. In one specific embodiment, the object moved was a cursor portrayed as a sphere in a virtual reality display. Target objects were presented to the subject, who then proceeded to move the cursor to the target and receive a reward. In a noncoadaptive use of the algorithm as previously modified by a co-adaptation, unlearned targets were presented in the virtual reality system and the subject moved the cursor to these targets. In another embodiment, a robot arm was controlled by an animal subject.