Human Physiology/The Nervous System

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Summation

When excitatory synapses exceed the amount of inhibitory synapses there are, then the excitatory synapses will

prevail over the other. The same goes with inhibitory synapses, if there are more inhibitory synapses than excitatory,

the synapses will be inhibited. To determine all of this is called summation.

Classification by discharge patterns:

Neurons can be classified according to their electrophysiological characteristics (note that a single action potential is

not enough to move a large muscle, and instead will cause a twitch).

Tonic or regular spiking: 

Some neurons are typically constantly (or tonically) active. Example: interneurons in

neurostriatum.

Phasic or bursting: 

Neurons that fire in bursts are called phasic.

Fast spiking: 

Some neurons are notable for their fast firing rates. For example, some types of cortical inhibitory

interneurons, cells in globus pallidus.

Thin-spike: 

Action potentials of some neurons are more narrow compared to the others. For example, interneurons

in prefrontal cortex are thin-spike neurons.

Classification by neurotransmitter released:

Some examples are cholinergic, GABAergic, glutamatergic and dopaminergic neurons.