title: A Simple and Accurate Model to Predict Responses to Multi-electrode Stimulation in the Retina.
abstract: Implantable electrode arrays are widely used in therapeutic stimulation of the nervous system (e.g. cochlear, retinal, and cortical implants). Currently, most neural prostheses use serial stimulation (i.e. one electrode at a time) despite this severely limiting the repertoire of stimuli that can be applied. Methods to reliably predict the outcome of multi-electrode stimulation have not been available. Here, we demonstrate that a linear-nonlinear model accurately predicts neural responses to arbitrary patterns of stimulation using in vitro recordings from single retinal ganglion cells (RGCs) stimulated with a subretinal multi-electrode array. In the model, the stimulus is projected onto a low-dimensional subspace and then undergoes a nonlinear transformation to produce an estimate of spiking probability. The low-dimensional subspace is estimated using principal components analysis, which gives the neuron's electrical receptive field (ERF), i.e. the electrodes to which the neuron is most sensitive. Our model suggests that stimulation proportional to the ERF yields a higher efficacy given a fixed amount of power when compared to equal amplitude stimulation on up to three electrodes. We find that the model captures the responses of all the cells recorded in the study, suggesting that it will generalize to most cell types in the retina. The model is computationally efficient to evaluate and, therefore, appropriate for future real-time applications including stimulation strategies that make use of recorded neural activity to improve the stimulation strategy.
authors.affiliation: National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, Australia.|Department of Electrical and Electronic Engineering, NeuroEngineering Laboratory, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Matias I
authors.initials: MI
authors.lastname: Maturana
authors.affiliation: Department of Physics, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Nicholas V
authors.initials: NV
authors.lastname: Apollo
authors.affiliation: National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, Australia.
authors.forename: Alex E
authors.initials: AE
authors.lastname: Hadjinicolaou
authors.affiliation: Department of Physics, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Garrett
authors.affiliation: National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, Australia.|Department of Electrical and Electronic Engineering, NeuroEngineering Laboratory, University of Melbourne, Parkville, Victoria, Australia.|Department of Optometry and Vision Sciences, ARC Centre of Excellence for Integrative Brain Function, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Shaun L
authors.initials: SL
authors.lastname: Cloherty
authors.affiliation: Department of Electrical and Electronic Engineering, NeuroEngineering Laboratory, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Kameneva
authors.affiliation: Department of Electrical and Electronic Engineering, NeuroEngineering Laboratory, University of Melbourne, Parkville, Victoria, Australia.|Centre for Neural Engineering, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: David B
authors.initials: DB
authors.lastname: Grayden
authors.affiliation: National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, Australia.|Department of Optometry and Vision Sciences, ARC Centre of Excellence for Integrative Brain Function, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Ibbotson
authors.affiliation: National Vision Research Institute, Australian College of Optometry, Carlton, Victoria, Australia.|Department of Optometry and Vision Sciences, ARC Centre of Excellence for Integrative Brain Function, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Hamish
authors.initials: H
authors.lastname: Meffin
mesh_terms: D000200:Action Potentials; D000818:Animals; D019295:Computational Biology; D066298:In Vitro Techniques; D016014:Linear Models; D008959:Models, Neurological; D058117:Neural Prostheses / Q000706:statistics & numerical data; D017711:Nonlinear Dynamics; D025341:Principal Component Analysis; D011474:Prosthesis Design; D051381:Rats; D020318:Rats, Long-Evans; D012160:Retina / Q000166:cytology / Q000502:physiology*; D012165:Retinal Ganglion Cells / Q000502:physiology