Structures, Materials, and Processes at the Electrode-to-Tissue Interface

  • Aditi RayEmail author
  • James D. Weiland


This chapter reviews the basic concepts of neural stimulation along with safety considerations for both the electrode and tissue. The section on electrode–electrolyte interface describes the basic mechanism of charge injection at the interface introducing the reader to the electrode double layer. The use of circuit models to represent the physical processes at the interface and in the bulk tissue is discussed. The next section provides a detailed description of the biopotential electrode along with measurement techniques used in electrode characterization. Following this, an overview of popular electrode materials for neural stimulation is provided for the reader. These include conventional materials such as platinum and iridium oxide, as well as newer materials like conducting polymers and carbon nanotubes. The next section reviews the concept of extracellular stimulation introducing the reader to Goldman Equation used to describe the membrane potential. Finally the section dedicated to safe stimulation of tissue describes the mechanisms of neural injury and parameters considered to ensure safe neural stimulation. Special emphasis is placed on safety studies of retinal stimulation.


Titanium Nitride Charge Injection Neural Stimulation Iridium Oxide Return Electrode 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Anodic iridium oxide films


Complimentary metal-oxide semiconductor


Carbon nanotubes


Constant phase element


Cyclic voltammetry


Early axonal degeneration


Electrochemical impedance spectroscopy




Inner helmholtz plane


Outer helmholtz plane


Phosphate buffered saline




Post stimulus time histograms


Stimulation induced depression in neuronal excitability


Sputtered iridium oxide film


Titanium nitride


Thermal iridium oxide film


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Department of Biomedical EngineeringLos AngelesUSA

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