Abstract：
:Propagation speed of an impulse is influenced by previous activity. A pulse following its predecessor too closely may travel more slowly than a solitary pulse. In contrast, for some range of interspike intervals, a pulse may travel faster than normal because of a possible superexcitable phase of its predecessor's wake. Thus, in general, pulse speeds and interspike intervals will not remain constant during propagation. We consider these issues for the Hodgkin-Huxley cable equations. First, the relation between speed and frequency or interspike interval, the dispersion relation, is computed for particular solutions, steadily propagating periodic wave trains. For each frequency, omega, below some maximum frequency, omega max, we find two such solutions, one fast and one slow. The latter are likely unstable as a computational example illustrates. The solitary pulse is obtained in the limit as omega tends to zero. At high frequency, speed drops significantly below the solitary pulse speed; for 6.3 degrees C, the drop at omega max is greater than 60%. For an intermediate range of frequencies, supernormal speeds are found and these are correlated with oscillatory swings in sub- and superexcitability in the return to rest of an impulse. Qualitative consequences of the dispersion relation are illustrated with several different computed pulse train responses of the full cable equations for repetitively applied current pulses. Moreover, changes in pulse speed and interspike interval during propagation are predicted quantitatively by a simple kinematic approximation which applies the dispersion relation, instantaneously, to individual pulses. One example shows how interspike time intervals can be distorted during propagation from a ratio of 2:1 at input to 6:5 at a distance of 6.5 cm.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Miller RN,Rinzel Jdoi
10.1016/S0006-3495(81)84847-3subject
Has Abstractpub_date
1981-05-01 00:00:00pages
227-59issue
2eissn
0006-3495issn
1542-0086pii
S0006-3495(81)84847-3journal_volume
34pub_type
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pub_type： 杂志文章
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更新日期：1996-08-01 00:00:00
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更新日期：2000-08-01 00:00:00
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pub_type： 杂志文章
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更新日期：1979-05-01 00:00:00
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更新日期：1984-06-01 00:00:00
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更新日期：2003-06-01 00:00:00
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更新日期：2004-04-01 00:00:00
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更新日期：1987-03-01 00:00:00
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更新日期：2017-03-14 00:00:00
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更新日期：2000-02-01 00:00:00
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