title: Extracellular stimulation window explained by a geometry-based model of the neuron-electrode contact.
abstract: Extracellular stimulation of single cultured neurons which are completely sealing a microelectrode is usually performed using anodic or biphasic currents of at least 200 nA. However, recently obtained experimental data demonstrate the possibility to stimulate a neuron using cathodic current pulses with less amplitude. Also, a stimulation window is observed. These findings can be explained by a finite-element model which permits geometry-based electrical representation of the neuron-electrode interface and can be used to explore the required conditions for extracellular stimulation in detail. Modulation of the voltage sensitive channels in the sealing part of the membrane appears to be the key to successful cathodic stimulation. Furthermore, the upper limit of the stimulation window can be explained as a normal consequence of the neuronal membrane electrophysiology.
authors.affiliation: Institute for Biomedical Technology, Signals and Systems Group, Faculty of Electrical Engineering, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands. J.R.Buitenweg@el.utwente.nl
authors.forename: Jan Reinoud
authors.initials: JR
authors.lastname: Buitenweg
authors.forename: Wim L C
authors.initials: WL
authors.lastname: Rutten
authors.forename: Enrico
authors.initials: E
authors.lastname: Marani
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D002448:Cell Adhesion; D002462:Cell Membrane / Q000502:physiology; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible; D003198:Computer Simulation; D004558:Electric Stimulation / Q000295:instrumentation / Q000379:methods*; D004574:Electromagnetic Fields; D004594:Electrophysiology / Q000295:instrumentation / Q000379:methods; D005110:Extracellular Space / Q000502:physiology*; D020342:Finite Element Analysis; D005727:Ganglia, Spinal / Q000502:physiology; D015640:Ion Channel Gating / Q000502:physiology*; D007473:Ion Channels / Q000502:physiology; D008839:Microelectrodes; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology*; D051381:Rats; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D020099:Coated Materials, Biocompatible; D007473:Ion Channels