Summary
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1.
The electrical response released by the slime mold,Physarum polycephalum, through mechanical and electrical stimuli disobeys the all-or-none law.
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2.
A stimulating current flowing outwards through the surface of the protoplasm is more effective in evoking a response than a current flowing in the opposite direction.
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3.
The process underlying electrical responses is the same irrespective of the means of stimulation, either mechanical or electrical.
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4.
The strength-duration relation agrees well with the Weiss' formulao=b (1+k/t, in whichb (rheobase) is 2–10 volts andk (chronaxie) is approximately 1 millisecond.
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5.
The “action potential” of the slime mold accompanies a simultaneous change in the electric impedance of the protoplasm. There is always a close parallelism between them.
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6.
Protoplasmic flow can proceed unhindered at the moment when electrical responses are induced.
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Literature
Cole, K. S., and H. J. Curtis, 1938, Electric impedance of Nitella during activity. J. Gen. Physiol.22, 37–64.
— 1939, Electric impedance of the squid giant axon during activity. J. Gen. Physiol.22, 649–670.
Heilbrunn, L. V., 1943, An outline of general physiology. 2nd ed. Philadelphia and London.
Kamiya, N., and S. Abe, 1950, Bioelectric phenomena in the myxomycete plasmodium and their relation to the protoplasmic flow. J. Colloid Sci. 5 (1).
Katz, B., 1942, Impedance changes in frog's muscle associated with electrotonic and “end-plate” potentials. J. Neurophysiol.5, 169–184.
Kuffler, S. W., 1942, Further study on transmission in an isolated nerve-muscle fibre preparation. J. Neurophysiol.5, 309–322.
Lapicque, L., 1926, L'excitabilité en fonction du temps. Presses universitaires, Paris.
Seifriz, W., and N. Epstein, 1941, Shock anesthesia in myxomycetes. Biodynamica3, (67), 191–197.
Tasaki, I., and K. Mizuguchi, 1949, The changes in the electric impedance during activity as the effect of alkaloids and polarization upon the bioelectric processes in the myelinated nerve fiber. Bioch. et Biophys. Acta3, 484–493.
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Tasaki, I., Kamiya, N. Electrical response of a slime mold to mechanical and electrical stimuli. Protoplasma 39, 333–343 (1950). https://doi.org/10.1007/BF01249160
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DOI: https://doi.org/10.1007/BF01249160