Synapse is the psychic network through which the Hive Mind of the Tyranids controls its countless organisms, binding an entire swarm into a single unified will. Radiating from powerful synapse-creatures such as Warriors, Tyrants, and the towering bio-titans, this invisible web of thought reaches out to direct even the most mindless of the brood.
The lesser Tyranid organisms, from the swarming Hormagaunts to the mighty Carnifex, possess little intellect of their own. Within the range of a synapse-creature they act with cold, coordinated purpose, executing the Hive Mind's strategies with flawless discipline. Sever that connection, however, and the swarm's behaviour changes utterly: some creatures fall into feral savagery, while others simply halt, purposeless without the guiding will.
For this reason, the defenders of the Imperium learn to hunt the synapse-creatures above all other targets, for to break the network is to shatter the swarm's cohesion. Yet the Hive Mind is vast and adaptive, and where one synapse node falls, the Great Devourer breeds a dozen more to take its place.