Artificial cortico-muscular connection via neural interface to regain volitional control of limb movements

Abstract

Motor impairment following stroke is one of the most important issues to be addressed in clinical care. In this review, we summarize a study in which lost volitional motor control of the hand was regained in a monkey model of stroke using an “artificial cortico-muscular connection” (ACMC) via a neural interface that bypassed the damaged neural pathway after stroke. The ACMC was produced by a computer interface that can detect the high-gamma cortical oscillations and converted in real-time to activity-contingent electrical stimuli delivered to the paralyzed muscles. As a result, within 20 min, the monkeys learned rapidly to use the ACMC and reacquired volitional motor control of the affected hand. Learning to use the ACMC was achieved regardless of whether the input signal was extracted from the primary motor area or the primary somatosensory area, and the activation areas of the input high-gamma signals were changed to concentrate around the arbitrarily-assigned input electrode as learning progressed. This study may have the potential to lead to the development of a clinically effective neural prosthesis to regain lost motor function by bypassing the lesion site and activating paralyzed muscles via an artificial neural connection, even after a limb is paralyzed due to stroke.