Abstract
Current clamp data of the squid axon indicate that there is a qualitative change in the adaptive response as the magnitude of the current step is increased. Large stimulus currents have a strong inhibitory effect on spike generation and on active responses in general. Such currents always lead to only one action-potential and to the elimination of post-spike subthreshold oscillation. In view of a direct connection between stimulus current and potassium current I K, the potassium channel of the Hodgkin-Huxley model is reinterpreted in a natural way such that the K+ conductance is directly dependent on I K in addition to a voltage dependence. The I-Kdependence seems to dominate whenever the stimulus current is greater than approximately 35 μA/cm2. For current ramps, and large current steps, such a current formulation leads to good agreement with the data.
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Research supported by NIH grants NS-5494 and NS-11 695. Computer facilities were made available by a grant from the U.S. Air Force Office of Scientific Research AFSC-1221.
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Fohlmeister, J.F. Adaptation and accommodation in the squid axon. Biol. Cybernetics 18, 49–60 (1975). https://doi.org/10.1007/BF00337055
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DOI: https://doi.org/10.1007/BF00337055