This concept is dependent on the theories which are related to the current that passes through a conductor and on potential differences. When the action potential gets triggered then the spine pushes the neurotransmitters from the terminal of presynaptic to postsynaptic.
It starts from a point and soon spreads to the dendrites entire length. Then, it propagates down the axon.
The process of synaptic potential is complex which happens because of the action potential that crosses the membrane of the neuron.
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