抄録
When V-t relation was calculated by using bipolar stimulus on excised single nerve fibre, it appeared roughly a hyperbola. However, Vt-t relation did not appear perfectly lineal. Especially in the zone where the utilizing time is short, it bended downwards. Consequently, Weiss's experimental formula did not stand.
When Hill's theoretical formula was viewed from the experimental results, the local potential constant (κ) became larger as the utilizing time became longer, and thus it was learnt that κ is the function of t. The constant (p) in Sakamoto's theory did not become a constant, but it became larger as the utilizing time was extended. Thus, it was learnt that p is also the function of t.
As κ is the value direct in proportion to chronaxie, the increase of κ by the extention of utilizing time means that increase of chronaxie, thus it was learnt that the irritability becomes lower as the utilizing time becomes longer.
The above diversion from the theoretical formula is primarily attributable to the anelectrotonus effect of the anode located in the proximity of the cathode. As the anelec-trotonus develops gradually, it is not developed sufficiently with a short period application even at a high voltage. However, if the utilizing time is extended, the anelectrotonus is developed to a fair degree even at a low voltage. The above is the reason why stronger anelectrotonus effect is exercised with a longer utilizing time than a shorter utilizing time, thus the irritability become lower. Consequently, for the purpose to avoid the influence of the anode side in the dipolar stimulation, application of electric current during a short period of time less than 0.3 msec is recommended.
