Grant: Project Grant

Motor deficits resulting from disorders such as stroke, spinal cord injury (SCI), or Parkinson's Disease (PD) have a large societal cost. While these disorders impact different brain structures, their net effect is the same: the muscle contractions causing movement are altered due to abnormal communication between brain circuits and the spinal cord. Spinal epidural spinal cord stimulation (sEES)-which directly activates spinal neurons to modulate muscle output-shows great promise in providing rapid and effective alleviation of these motor deficits. Indeed, sEES has already improved walking, reaching, and grasping in clinical population suffering from SCI, PD, and stroke. However, effective and natural sEES requires tight synchronization between applied stimulation and the motor intention of the patient. Current systems apply either tonic sEES or use low-resolution control schemes such as external sensors. Recent work has proposed to directly link sEES to control signals decoded from brain activity in the motor cortex. Yet, such brain-controlled EES devices are far from widespread application due to the immense challenge of integrating with the complex dynamics of the nervous system. This project aims to address this gap by studying the interplay between spinal stimulation and volitional movement signals in the motor cortex. Our long-term goal is the development of sEES devices that seamlessly integrate with existing biological circuitry.