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Some Possible Limits on the Minimum Electrical Signals of Biological Significance

  • Frank S. Barnes
  • Mohammad Seyed-Madani

Abstract

It is of interest to consider what might be the lowest-level electric and magnetic signals that are biologically important. This is important in helping to decide what experiments are worth performing, as well as in setting safety standards. Deciding what the lowest-level fields or currents are is not a simple issue, because the biological effects of an externally applied electric field or current may be dependent on the particular cell or organ to which they are applied as well as on the time of their application. The amplitude of the current, the field direction, the pulse length, the frequency and the shape of the signal may all be important when the system is nonlinear or time-dependent. Thus two current pulses of the same size and shape may have quite different effects on the firing rate of a pace-maker cell, depending on the point of the firing cycle at which they are injected or on the closeness of the repetition rate to the natural firing rate. In addition, we can reasonably expect that the minimum signal for which we can detect a biological change will decrease as our measuring techniques improve, and as our biological understanding improves.

Keywords

Firing Rate Noise Voltage Squid Axon Mylar Film Minimum Signal Level 
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.

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Copyright information

© Springer Science+Business Media New York 1987

Authors and Affiliations

  • Frank S. Barnes
    • 1
  • Mohammad Seyed-Madani
    • 1
  1. 1.Dept. of Electrical & Computer EngineeringUniversity of ColoradoBoulderUSA

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