title: Electrical activity of ON and OFF retinal ganglion cells: a modelling study.
abstract: OBJECTIVE
  Retinal ganglion cells (RGCs) demonstrate a large range of variation in their ionic channel properties and morphologies. Cell-specific properties are responsible for the unique way RGCs process synaptic inputs, as well as artificial electrical signals such as that from a visual prosthesis. A cell-specific computational modelling approach allows us to examine the functional significance of regional membrane channel expression and cell morphology.
  
  
  METHODS
  In this study, an existing RGC ionic model was extended by including a hyperpolarization activated non-selective cationic current as well as a T-type calcium current identified in recent experimental findings. Biophysically-defined model parameters were simultaneously optimized against multiple experimental recordings from ON and OFF RGCs.
  
  
  RESULTS
  With well-defined cell-specific model parameters and the incorporation of detailed cell morphologies, these models were able to closely reconstruct and predict ON and OFF RGC response properties recorded experimentally.
  
  
  CONCLUSIONS
  The resulting models were used to study the contribution of different ion channel properties and spatial structure of neurons to RGC activation. The techniques of this study are generally applicable to other excitable cell models, increasing the utility of theoretical models in accurately predicting the response of real biological neurons.
authors.affiliation: Graduate School of Biomedical Engineering, UNSW Australia, Sydney, NSW 2052, Australia.
authors.forename: Tianruo
authors.initials: T
authors.lastname: Guo
authors.forename: David
authors.initials: D
authors.lastname: Tsai
authors.forename: John W
authors.initials: JW
authors.lastname: Morley
authors.forename: Gregg J
authors.initials: GJ
authors.lastname: Suaning
authors.forename: Tatiana
authors.initials: T
authors.lastname: Kameneva
authors.forename: Nigel H
authors.initials: NH
authors.lastname: Lovell
authors.forename: Socrates
authors.initials: S
authors.lastname: Dokos
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D003198:Computer Simulation; D006801:Humans; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology; D012165:Retinal Ganglion Cells / Q000502:physiology*; D012984:Software; D057488:Visual Prosthesis