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  2. Action potential - Wikipedia

    en.wikipedia.org/wiki/Action_potential

    When an action potential arrives at the end of the pre-synaptic axon (top), it causes the release of neurotransmitter molecules that open ion channels in the post-synaptic neuron (bottom). The combined excitatory and inhibitory postsynaptic potentials of such inputs can begin a new action potential in the post-synaptic neuron.

  3. Threshold potential - Wikipedia

    en.wikipedia.org/wiki/Threshold_potential

    In electrophysiology, the threshold potential is the critical level to which a membrane potential must be depolarized to initiate an action potential. In neuroscience , threshold potentials are necessary to regulate and propagate signaling in both the central nervous system (CNS) and the peripheral nervous system (PNS).

  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. Biological neuron model - Wikipedia

    en.wikipedia.org/wiki/Biological_neuron_model

    Fig. 1. Neuron and myelinated axon, with signal flow from inputs at dendrites to outputs at axon terminals. The signal is a short electrical pulse called action potential or 'spike'. Fig 2. Time course of neuronal action potential ("spike"). Note that the amplitude and the exact shape of the action potential can vary according to the exact ...

  6. Hyperpolarization (biology) - Wikipedia

    en.wikipedia.org/wiki/Hyperpolarization_(biology)

    Diagram of membrane potential changes during an action potential. Hyperpolarization is a change in a cell's membrane potential that makes it more negative. Cells typically have a negative resting potential, with neuronal action potentials depolarizing the membrane.

  7. Hodgkin–Huxley model - Wikipedia

    en.wikipedia.org/wiki/Hodgkin–Huxley_model

    In order to arrive at the complete solution for a propagated action potential, one must write the current term I on the left-hand side of the first differential equation in terms of V, so that the equation becomes an equation for voltage alone.

  8. Outline of the human nervous system - Wikipedia

    en.wikipedia.org/wiki/Outline_of_the_human...

    An action potential (or nerve impulse) is a transient alteration of the transmembrane voltage (or membrane potential) across the membrane in an excitable cell generated by the activity of voltage-gated ion channels embedded in the membrane. The best known action potentials are pulse-like waves that travel along the axons of neurons. Membrane ...

  9. File:Membrane Permeability of a Neuron During an Action ...

    en.wikipedia.org/wiki/File:Membrane_Permeability...

    In the stages of an action potential, the permeability of the membrane of the neuron changes. At the resting state (1) , sodium and potassium ions are unable to pass through the membrane, and the neuron has a negative charge inside (mainly due to the large proteins that are negatively charged, as well as the lower amount of positive K+ ions ...