Affiliations: Department of Neurology, Campus Bio-Medico University, Rome, Italy | Biomedical Robotics and Biomicrosystems Lab., University Campus Bio-Medico, Rome, Italy | LET's – ISTC – CNR, Ospedale Fatebenefratelli, Isola Tiberina, Rome, Italy | Institute of Neuroscience, Newcastle University, Medical School, Newcastle upon Tyne, UK | Casa di Cura S. Raffaele, Cassino and IRCCS S. Raffaele-Pisana, Rome, Italy | Institute of Neurology, Catholic University, Rome, Italy
Note: [] These authors contributed equally to this work as first author.
Note: [] These authors contributed equally to this work as first author. Corresponding author: Dr. Camillo Porcaro, LET'S-ISTC-CNR, Department of Clinical Neuroscience, Fatebenefratelli Hospital – Isola Tiberina, 00186 Rome, Italy. E-mail: camillo.porcaro@istc.cnr.it
Note: [] These authors contributed equally to this work as last author.
Note: [] These authors contributed equally to this work as last author.
Abstract: Purpose: This work investigates how a direct bidirectional connection between brain and hand prosthesis modifies the bi-hemispheric sensorimotor system devoted to the movement control of the lost limb. Hand prostheses are often unable to satisfy users' expectations, mostly due to the poor performance of their interfacing system. Neural Interfaces implanted inside nerves of the stump offer the advantage of using the bidirectional neural pathways ‘naturally’ dispatching signals to control proper hand actions and feed-back sensations. Learning to control a neurally-interfaced hand prosthesis and decode sensory information was previously observed to reduce the inter-hemispheric asymmetry of cortical motor maps and the clinical symptoms of phantom limb syndrome. Methods: Electroencephalographic (EEG) data was analysed using Functional Source Separation (FSS), a semi-blind method that incorporates prior knowledge about the signal of interest into data decomposition to give access to cortical patch activities. Results: Bi-hemispheric cortices showed normalization of their activity (topographical and spectral patterns) and of functional connectivity between homologous hand controlling areas, during the delivery of the motor command to the cybernetic prosthesis. Conclusions: The re-establishment of central-peripheral communication with the lost limb induced by a neurally-interfaced hand prosthesis produces beneficial plastic reorganization, not only restructuring contralateral directly-connected control areas, but also their functional balance within the bi-hemispheric system necessary for motor control.
