Scientific Questions

The following main scientific questions (SQs) will be investigated by the NEBIAS Consortium:

• SQ1: Restorability of the natural neural “pathway”. The NEBIAS proposal aims at investigating the potentials and limits of intraneural implantable interfaces to restore the bidirectional link between external artificial devices and the nervous system. Therefore, the implantation will be done more distally (to control a hand prosthesis) or more proximally (for a transhumeral prosthesis).
• SQ2: Brain/PNS connection. The NEBIAS proposal will represent a unique opportunity to gather more information about the way the CNS and PNS can generate movements and process the (artificial) sensory information. Even if we will address a specific and artificial case (controlling prostheses) the results could help to understand motor control in a more general way.
• SQ3: Neural plasticity. Using a multi-modal cortical analysis the modifications of the activities of the central nervous system will be investigated during the control of the NEBIAS prostheses.
• SQ4: Sensory feedback. What kind of information has to be provided to the user and to the artificial control/processing algorithms in order to provoke an increased and more effective understanding of the environment? Is sensory feedback able to improve the performance of the user?
• SQ5: Motor learning. Learning new motor skills requires a bulk of repetitive training during which the various stages of the new skill need to be allocated within a fluid and continuous movement to be executed as fast and precisely as possible. Such level of excellence in not reachable until a mainly cortical and voluntary control is needed. Maximum level of performance is reached once the new skill becomes automatic, namely when it stops needing step-by-step voluntary and cortical control. Thereafter, if further trained, also the automatic—mainly subcortical—motor skills can improve in their efficacy until reaching a plateau dictated by the general context (individual motor abilities such as strength, speed, sense of rhythm, balance, etc.). However, in the experimental model we are proposing here, the amount of real learning of new motor skills is minimal since the subject is required to convey to the robotic hand the very same motor order as previously dispatched to the ‘real’ hand.
• SQ6: Assessment of performance of the user. The NEBIAS Consortium will address the issues related to the usability of the neurocontrolled prosthesis by the user. The following questions will be also investigated: (i) are the performances of these systems good enough to address real-life situations? (ii) Which level of shared control between the user’s brain and the machine is required for an effective use of the prosthesis? (iii) Is it possible to control/use the prosthesis while carrying out other activities? To answer this question specific experiments (e.g., dual task trials, assistive hand assessment, assistive hand assessment procedures, box and blocks test, etc.) and assessment parameters will be identified and used during the project.