Biological Cybernetics

, Volume 18, Issue 1, pp 49–60 | Cite as

Adaptation and accommodation in the squid axon

  • Jürgen F. Fohlmeister


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 IK, the potassium channel of the Hodgkin-Huxley model is reinterpreted in a natural way such that the K+ conductance is directly dependent on IK 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.


Potassium Channel Active Response Qualitative Change Direct Connection Current Formulation 
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Copyright information

© Springer-Verlag 1975

Authors and Affiliations

  • Jürgen F. Fohlmeister
    • 1
  1. 1.Laboratory of NeurophysiologyUniversity of MinnesotaMinneapolisUSA

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