Search results
Results from the WOW.Com Content Network
After initiation of an action potential, the refractory period is defined two ways: The absolute refractory period coincides with nearly the entire duration of the action potential. In neurons , it is caused by the inactivation of the voltage-gated sodium channels that originally opened to depolarize the membrane.
The afterhyperpolarisation is one of the processes that contribute to the refractory period. Afterhyperpolarization, or AHP, is the hyperpolarizing phase of a neuron's action potential where the cell's membrane potential falls below the normal resting potential. This is also commonly referred to as an action potential's undershoot phase. AHPs ...
The period during which no new action potential can be fired is called the absolute refractory period. [43] [44] [45] At longer times, after some but not all of the ion channels have recovered, the axon can be stimulated to produce another action potential, but with a higher threshold, requiring a much stronger depolarization, e.g., to −30 mV.
Cardiac cells have two refractory periods, the first from the beginning of phase 0 until part way through phase 3; this is known as the absolute refractory period during which it is impossible for the cell to produce another action potential. This is immediately followed, until the end of phase 3, by a relative refractory period, during which a ...
Neurons naturally become hyperpolarized at the end of an action potential, which is often referred to as the relative refractory period. Relative refractory periods typically last 2 milliseconds, during which a stronger stimulus is needed to trigger another action potential. Cells can also become hyperpolarized depending on channels and ...
Neurons are diverse with respect to morphology and function. Thus, ... resulting in an undershoot phase or absolute refractory period. The undershoot phase occurs ...
Why the refractory period happens, however, still isn't one of those things. There can be a lot of variables involved in the equation of a refractory timetable, but three that may play a role are ...
concentration was approaching that of the second impulse, facilitation was increased. In this first experiment, stimuli were presented in intervals of 100 ms between the first and second stimuli. An absolute refractory period was reached when intervals were about 10 ms apart.