The basic principle of the functional activity of the nervous system is the propagation of central nervous excitation from neuron to neuron and from neuron to neuronal fiber through electrical or chemical synaptic transmission.
Electrical synaptic transmission is non-directional and works by using the excitation and inhibition of neuronal synapses to generate potential changes, and information is transmitted between neurons and between neurons and effectors through synapses, allowing the transmission of information between contact sites or structures to realize the functional activities of the nervous system.
Chemical synapses are capable of both directional and non-directional transmission, but require a transmitter to act within the synapse or on a portion of the membrane structure for localized transmission, which is more efficient than electrical synapses, but can only be unidirectional.
In addition, there are two special synaptic transmission methods, including nerve-muscle and nerve-gland, which can transmit signals directly to the active parts of the nervous system to realize the functional activities of the nervous system.