||"The best physiological description of how an action potential induces phasic,
synchronous neurotransmitter release was obtained for the synapse formed by
the calyx of Held, the only synapse for which models are available that accurately
account for all properties of release (reviewed in Meinrenken et al. 2003). The calyx
of Held forms a large nerve terminal (~15 µm diameter) that envelops the soma
of the postsynaptic neuron like a cup, hence its name." Wiki-"The Calyx of Held is a particularly large synapse in the mammalian auditory central nervous system".