chapter  5
10 Pages

Synaptic transmission

The function of a neuron is to communicate or relay information to another cell by way of an electrical impulse. A

synapse

is the site at which the impulse is transmitted from one cell to the next. A neuron may terminate on a muscle cell, glandular cell, or another neuron. The discussion in this chapter will focus on neuron-to-neuron transmission. At these types of synapses, the

presynaptic neuron

transmits the impulse

toward

the synapse and the

postsynaptic neuron

transmits the impulse

away

from the synapse. Specifically, it is the axon terminal of the presynaptic neuron that comes into contact with the cell body or the dendrites of the postsynaptic neuron. Most neurons, particularly in the CNS, receive thousands of inputs. As will become evident, the transmission of the impulse at the synapse is

unidirectional

and the presynaptic neuron influences activity of the postsynaptic neuron only.