ELECTRONIC FEATURE EXTRACTOR FOR ACTION POTENTIALS

An electronic feature-extraction system is presented that simplifies the measurement of five parameters of the action potential. These parameters are: (a) the peak amplitude of the action potential, (b) the maximum slope, (c) the threshold as measured at the inflection on the rising phase of the action potential, (d) the time interval between the inflection and the peak of the action potential, and (e) the time constant of the 'exponentially' rising foot of the action potential. Using this equipment, the foot of the action potential was found in the squid giant axon to be close to a pure exponential only at temperatures less than 15° C. © 1979 IFMBE.