In addition to its intraganglionic role in bilateral coordination of feeding in Aplysia, GABAergic signaling also contributes to motor program generation and specification via interganglionic
projections from the cerebral ganglion.
Cervical interganglionic branch or cervical sympathetic trunk: The most rostral part of the sympathetic trunk was separated from the rostromedial margin of the vagus nerve over the medial surface of middle part of the caudal belly of the digastric muscle, approximately 2.5-4.5 mm distocaudal to the ventral pole of the CCG.
The most rostral part of the cervical interganglionic branch little distal to the ventral pole of the CCG laterally coursed by the pharyngeal branch of the vagus nerve, while passing rostrally toward the pharynx (Figs.
The cerebro-pedal, cerebro-pleural, and cerebro-buccal connectives, as well as the cerebral commissure were supplied by numerous GLU-LIR processes, indicating a well-developed interganglionic GLUergic connectivity.
The relatively small number of GLU-LIR neurons, combined with rich arborization and projection patterns at both central (ganglion neuropil, connectives and commissures) and peripheral (nerves and tissue) levels, indicate a broad involvement of this amino acid in different regulatory processes, including intra- and interganglionic integration, as well as afferent and efferent roles.
They have proprioceptors similar to those of lobsters, but they differ in terms of their balancing systems and their condensed nervous system, which allows rapid interganglionic conduction.
Compared with the ladder-like nerve cord of macrurans (crayfish and lobsters), their nervous system shows condensation and fusion of thoracic ganglia, allowing rapid interganglionic conduction of impulses.