title: Smaller, softer, lower-impedance electrodes for human neuroprosthesis: a pragmatic approach.
abstract: Finding the most appropriate technology for building electrodes to be used for long term implants in humans is a challenging issue. What are the most appropriate technologies? How could one achieve robustness, stability, compatibility, efficacy, and versatility, for both recording and stimulation? There are no easy answers to these questions as even the most fundamental and apparently obvious factors to be taken into account, such as the necessary mechanical, electrical and biological properties, and their interplay, are under debate. We present here our approach along three fundamental parallel pathways: we reduced electrode invasiveness and size without impairing signal-to-noise ratio, we increased electrode active surface area by depositing nanostructured materials, and we protected the brain from direct contact with the electrode without compromising performance. Altogether, these results converge toward high-resolution ECoG arrays that are soft and adaptable to cortical folds, and have been proven to provide high spatial and temporal resolution. This method provides a piece of work which, in our view, makes several steps ahead in bringing such novel devices into clinical settings, opening new avenues in diagnostics of brain diseases, and neuroprosthetic applications.
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia Genoa, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Castagnola
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia Genoa, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Ansaldo
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia Genoa, Italy.
authors.forename: Emma
authors.initials: E
authors.lastname: Maggiolini
authors.affiliation: Struttura Complessa di Neurochirurgia, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia Udine, Italy.
authors.forename: Tamara
authors.initials: T
authors.lastname: Ius
authors.affiliation: Struttura Complessa di Neurochirurgia, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia Udine, Italy.
authors.forename: Miran
authors.initials: M
authors.lastname: Skrap
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia Genoa, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Ricci
authors.affiliation: Robotics, Brain and Cognitive Sciences Department, Istituto Italiano di Tecnologia Genoa, Italy ; Section of Human Physiology, Department of Biomedical Sciences, University of Ferrara Ferrara, Italy.
authors.forename: Luciano
authors.initials: L
authors.lastname: Fadiga
keywords: Intracortical microelectrodes; brain-conformability; carbon nanotubes; conductive polymers; hydrogel; micro-electrocorticography (ECoG); neural recording; neural stimulation