title: Modelling the effect of hydration on skin conductivity.
abstract: BACKGROUND
  Electrical signals are recorded from and sent into the body via the skin in a number of applications. In practice, skin is often hydrated with liquids having different conductivities so a model was produced in order to determine the relationship between skin impedance and conductivity.
  
  
  METHODS
  A model representing the skin was subjected to a variety of electrical signals. The parts of the model representing the stratum corneum were given different conductivities to represent different levels of hydration.
  
  
  RESULTS
  The overall impedance and conductivity of the cells did not vary at frequencies below 40 kHz. Above 40 kHz, levels of increased conductivity caused the overall impedance to decrease.
  
  
  CONCLUSIONS
  The variation in impedance with conductivity between 5 and 50 mSm-1can be modelled quadratically while variation in impedance with conductivity between 5 and 5000 mSm-1can be modelled with a double exponential decay.
authors.affiliation: Institute of Complex Systems and Simulation, University of Southampton, Southampton, UK.|Electronics and Computer Science, University of Southampton, Southampton, UK.
authors.forename: L
authors.initials: L
authors.lastname: Davies
authors.affiliation: Electronics and Computer Science, University of Southampton, Southampton, UK.
authors.forename: P
authors.initials: P
authors.lastname: Chappell
authors.affiliation: Electronics and Computer Science, University of Southampton, Southampton, UK.|Optoelectronics Research Centre, University of Southampton, Southampton, UK.
authors.forename: T
authors.initials: T
authors.lastname: Melvin
mesh_terms: D004553:Electric Conductivity; D017097:Electric Impedance; D005712:Galvanic Skin Response / Q000502:physiology*; D006801:Humans; D008954:Models, Biological; D012867:Skin / Q000378:metabolism*; D012879:Skin Physiological Phenomena; D014867:Water / Q000008:administration & dosage / Q000502:physiology*
chemical_list: D014867:Water
keywords: bioimpedance; modelling; skin conductance; skin potential