Microelectrodes signal distortion

At a recording microelectrode, ac electrode polarization, in addition to producing a frequency-sensitive voltage drop, may also introduce signal distortion. 

A rudimentary representation for an input circuit with glass microelectrodes (using a dc amplifier) is shown in Figure 7.5. represents the series resistance of the glass micropipette. A detailed description of electrode polarization problems was presented in Chapter 4. For this discussion it is sufficient to consider only the elements shown in Figure 7.5 since any signal distortion produced by electrode polarization can be incorporated into the description of. ... 

Signal distortion in electrophysiological recording systems may arise from a variety of sources series ac polarization impedance developed at electrode-electrolyte interfaces fluid interfaces in glass microelectrode systems and associated fluctuations of tip potentials and related phenomena stimulus-isolation units residual and stray capacitances not corrected for by compensating preamplifiers contact problems thermal noise and noise generated by other sources. 

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