Motor-parietal cortical neuroprosthesis with somatosensory feedback for restoring hand and arm functions in tetraplegic patients.

• Applicant: Dr. Christian Klaes
• Subject Area: Clinical Neurology; Neurosurgery and Neuroradiology ; Medical Physics, Biomedical Technology
• Term: from 2016 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 289947155

A neuroprosthesis is a system which allows a severely disabled person to control an extracorporeal robotic device with his or her thoughts. Recent developments in neuroprosthetics have great potential to increase the quality of life and autonomy for paralyzed patients. Although a couple of clinical studies for upper limb cortical prostheses have been started in the USA many aspects of neuroprosthetic systems remain open to research. It is not clear, for example, which areas of the brain are providing the best control signals. Most studies so far focused on the motor cortex and its low-level motor commands. In a recent human study my colleagues and I at Caltech could demonstrate that high-level cognitive signals which we derived from the posterior parietal cortex (PPC) can be used to drive a neuroprosthesis as well. The proposed project intends to combine the signals from both cortical areas - the motor cortex and PPC - to provide improved performance. Furthermore by utilizing intracortical microstimulation in the somatosensory cortex it is intended to elicit tactile sensations which are completely lost to tetraplegics who are paralyzed from the neck down. The implementation of effective somatosensory feedback is also likely to improve performance especially in fine motor tasks and has the potential to substantially improve quality of life. Another essential part of the project will be to use immersive virtual reality to study the influence of perspective, visual presentation and multiple control scenarios before transitioning to a physical robotic limb. Virtual reality provides us with the opportunity to experiment with multiple perspectives, control schemes and scenarios in a save and rapid way. Finally, it is intended to use a hybrid control system in which computer assistance is combined with cortical control signals. This combined system would be more robust against long-term signal degradation and could provide optimal assistance in activities of daily living for tetraplegic patients.

• DFG Programme: Independent Junior Research Groups
• Major Instrumentation: 2 x Neural Signal Processors, plus electrode arrays, connectors, headstages and micro stimulator
• Instrumentation Group: 3430 Elektro-Enzephalographen