Abstract:
:The space-clamped squid axon membrane and two versions of the Hodgkin-Huxley model (the original, and a strongly adapting version) are subjected to a first order dynamic analysis. Stable, repetitive firing is induced by phase-locking nerve impulses to sinusoidal currents. The entrained impulses are then pulse position modulated by additional, small amplitude perturbation sinusoidal currents with respect to which the frequencies response of impulse density functions are measured. (Impulse density is defined as the number of impulses per unit time of an ensemble of membranes with each membrane subject to the same stimulus). Two categories of dynamic response are observed: one shows clear indications of a corner frequency, the other has the corner frequency obscured by dynamics associated with first order conductance perturbations in the interspike interval. The axon membrane responds with first order perturbations whereas the unmodified Hodgkin-Huxley model does not. Quantitative dynamic signatures suggest that the relaxation times of axonal recovery excitation variables are twice as long as those of the corresponding model variables. A number of other quantitative differences between axon and models, including the values of threshold stimuli are also observed.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Fohlmeister JF,Adelman WJ Jr,Poppele REdoi
10.1016/S0006-3495(80)85078-8subject
Has Abstractpub_date
1980-04-01 00:00:00pages
79-97issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(80)85078-8journal_volume
30pub_type
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