text: For technical reasons, synaptic structure and function have been historically studied at unusually large model synapses, for example:
  * Squid giant synapse
  * Neuromuscular junction (NMJ), a cholinergic synapse in vertebrates, glutamatergic in insects
  * Ciliary calyx in the ciliary ganglion of chicks
  * Calyx of Held in the brainstem
  * Ribbon synapse in the retina
  * Schaffer collateral synapses in the hippocampus. These synapses are small, but their pre- and postsynaptic neurons are well separated (CA3 and CA1, respectively).