Action potential versus postsynaptic potential
From WikiLectures
| parametr | AP | PSP |
|---|---|---|
| significance | transmission of excitement without quality change (noise) over long distances | processing, connecting individual PSPs and deciding whether a new AP should be created |
| behaviour | all or nothing - the transmission is digital (even if it happens to change along the way, the
resulting cell will only evaluate whether the signal arrived or not) |
continuous, can have different values |
| amplitude | about 100 mV | 1–10 mV |
| duration | about 10–40 ms | 1–5 ms |
| ion channels | voltage controlled | chemically controlled |
| permeability especially for | Na+, K+ (fast channel) | K+ (leak channel) |
| localization | axons | postsynaptic membrane (soma = neuron body), dendrites) |
| spread (to distance) | no decrement (no amplitude reduction, up to meters) | with decrement (signal strength decreases, 10–100 μm) |
