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  2. Action potential - Wikipedia

    en.wikipedia.org/wiki/Action_potential

    As an action potential (nerve impulse) travels down an axon there is a change in electric polarity across the membrane of the axon. In response to a signal from another neuron, sodium- (Na +) and potassium- (K +)–gated ion channels open and close as the membrane reaches its threshold potential.

  3. Cardiac action potential - Wikipedia

    en.wikipedia.org/wiki/Cardiac_action_potential

    The slope of phase 0 on the action potential waveform (see figure 2) represents the maximum rate of voltage change of the cardiac action potential and is known as dV/dt max. In pacemaker cells (e.g. sinoatrial node cells ), however, the increase in membrane voltage is mainly due to activation of L-type calcium channels.

  4. Afterhyperpolarization - Wikipedia

    en.wikipedia.org/wiki/Afterhyperpolarization

    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 have been segregated into "fast", "medium", and "slow" components that appear to have distinct ...

  5. Excitatory postsynaptic potential - Wikipedia

    en.wikipedia.org/wiki/Excitatory_postsynaptic...

    In neuroscience, an excitatory postsynaptic potential (EPSP) is a postsynaptic potential that makes the postsynaptic neuron more likely to fire an action potential. This temporary depolarization of postsynaptic membrane potential , caused by the flow of positively charged ions into the postsynaptic cell, is a result of opening ligand-gated ion ...

  6. Quantitative models of the action potential - Wikipedia

    en.wikipedia.org/wiki/Quantitative_models_of_the...

    Figure FHN: To mimick the action potential, the FitzHugh–Nagumo model and its relatives use a function g(V) with negative differential resistance (a negative slope on the I vs. V plot). For comparison, a normal resistor would have a positive slope, by Ohm's law I = GV, where the conductance G is the inverse of resistance G=1/R.

  7. Electrotonic potential - Wikipedia

    en.wikipedia.org/wiki/Electrotonic_potential

    Electrotonic potentials represent changes to the neuron's membrane potential that do not lead to the generation of new current by action potentials. [1] However, all action potentials are begun by electrotonic potentials depolarizing the membrane above the threshold potential which converts the electrotonic potential into an action potential. [2]

  8. Compound action potential - Wikipedia

    en.wikipedia.org/wiki/Compound_action_potential

    Alike individual action potentials, CAP waveforms are typically biphasic presenting a negative and positive peak. The morphological attributes of the CAP (amplitude, spread, latency) depend on various factors including electrode placement, stimulus intensity, number of fibers recruited, the synchronization of action potentials, and conduction ...

  9. Ventricular action potential - Wikipedia

    en.wikipedia.org/wiki/Ventricular_action_potential

    The action potential of a ventricular myocyte. In electrocardiography, the ventricular cardiomyocyte membrane potential is about −90 mV at rest, [1] which is close to the potassium reversal potential. When an action potential is generated, the membrane potential rises above this level in five distinct phases. [1]