Synaptic Signaling

Neurons communicate with each other and with other cells mainly through chemical signaling at synapses.

These specialized regions are where the axon terminal of the presynaptic cell, which sends the message, comes into close proximity to the postsynaptic cell, which receives it.

The signal consists of neurotransmitter molecules, which are stored in membrane-bound organelles called synaptic vesicles within the axon terminal.

When an electrical signal, known as an action potential, happens in the presynaptic neuron, it causes these vesicles to fuse with the cell membrane.

As the vesicles fuse, they release neurotransmitters into the synaptic cleft, the narrow space between cells.

The neurotransmitters then diffuse across the cleft and bind to receptors on the postsynaptic cell. This binding triggers a response in the postsynaptic cell, which, in this case, is a neuron. As a result, an action potential may be produced.

Together, these synaptic signals allow neurons to pass information through neural circuits across the body.