The point of contact is known as the synapse. The receptive surfaces consist of the membrane of the cell body, the dendrites or the synaptic terminal of the axon. Communication between neurons can occur through electrical or chemical synaptic connections. Electrical synapses consist of low-resistance connections between the membranes of two neurons where a change in potential in a presynaptic neuron can be transmitted to a postsynaptic neuron with little attenuation. Electrical synapses are found extensively in the invertebrate and lower-vertebrate nervous system and at some sites in the mammalian nervous system.
Chemical synapses are the predominant type of interneuronal communication in the mammalian brain.
Action potentials in the presynaptic neuron cause the release of neurotransmitters from synaptic vesicles. The synaptic potentials produced in the postsynaptic membrane are graded responses, in contrast to the all or none behaviour of the action potential transmitted along axons.