Sensory Augmentation, Restoration, and Modulation Using a Spinal Neuroprosthesis

Indiana University Indianapolis, Indianapolis IN

Investigators

Linked publications, trials & patents

Abstract

Project Summary The physical world contains signals encompassing the entire electromagnetic spectrum, and yet human perception of the world is limited to our five senses. To augment our senses, it is essential to first develop methods that can effectively transmit high-bandwidth information to the brain. Researchers working on brain- machine interfaces have successfully extracted movement signals from the brain to control external devices. Yet, methods that augment, restore, or modulate sensory perception are currently limited. Lack of real-time sensory feedback from a brain-machine interface or neuroprosthetic device prevents optimal motor control and thus limits sensorimotor rehabilitation. Loss of sensation due to life-altering injuries and disorders affects the quality of life of millions of Americans. Thus, methods that mimic sensory signals and interface them directly with the brain are an unmet clinical need. This project proposes a novel spinal sensory neuroprosthetic interface using sensory spinal cord stimulation (SSCS) with the ability to augment, restore, and modulate sensory perceptions. This radically innovative approach has the potential to impact a wide array of neurological conditions by addressing sensory restoration and allows for the exploration of the limits of human sensory perception. Pre- clinical experiments in rodents and rhesus monkeys demonstrated that animals learn to detect and discriminate artificial sensations induced by SSCS. To achieve clinical translation of SSCS technology, this proposal involves a feasibility study, conducted in patients undergoing spinal cord stimulator implantation for the treatment of chronic pain. First, the relationship between SSCS-induced sensory perceptual thresholds, just-noticeable differences, and stimulation parameters will be established (Goal 1). Second, human subjects will be trained to detect and discriminate variations in signal intensity and orientation of non-native signals such as infrared, UV light, magnetic fields, etc. using SSCS-induced perceptual sense, and ultimately subjects will learn to use these novel perceptual abilities to navigate a spatial environment with non-native signal cues (Goal 2). Third, lower limb amputee subjects will learn to intuitively perceive movement and location of their prosthetic limbs during locomotion via real-time closed loop sensory feedback using SSCS (Goal 3). This project is innovative because it uses FDA-approved technology (spinal cord stimulation) in a new context, all without changing the patient’s standard-of-care. The ability to augment, restore, and modulate perceptions will be an unprecedented development in the field of sensory neuroprosthetics. Successful execution of proposed goals will not only launch a new line of augmentation research, but it will also showcase that SSCS can be widely applicable in the rehabilitation of patients suffering from sensory deficits due to neurological disorders and injuries.