Psychology – Gleitman
This continues until the pulse is strong enough to decrease the
potential to a critical point, the threshold.
Now a new phenomena occurs. The potential suddenly collapses; in fact, it overshoot the zero mark and for a brief moment the axon interior becomes positive
relative to the outside. This brief flare lasts about 1 millisecond and quickly subsides. The potential then returns to the resting state. This entire sequence of
electrical evets is called the action potential.
The all-or-none law:
One point must be stressed. Size of the reaction is unaffected by the intensity of the stimulus, once the stimulus is a t threshold level or above. Increasing the
stimulus value above this level will not increase the intensity of the action potential or affect its speed of conduction to other points in the fiber. This phenomenon
is sometimes referred to as the allornone-law of neuron stimulation
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