Vinculum
The Vinculum is the processing device at the core of every Borg vessel, which interconnects the minds of all the drones via a neural Interlink Frequency. It purges individual thoughts and disseminates information relevant to the Collective. The vinculum is equipped with several safeguards to prevent it from being deactivated, and is capable of adapting to new threats.
In 2375, a Borg vinculum in a debris field attempted to establish a link to Seven of Nine's cortical implants. The vinculum was malfunctioning, sending erratic orders that caused the neural patterns of previously assimilated individuals to surface in Seven's conciousness, with symptoms similar to multiple personality disorder.
The USS Voyager retrieved the vinculum and found that it had been infected with a synthetic pathogen, created by Species 6339 to attack the Borg. The crew was able to deactivate the vinculum by targeting its transneural matrix with a dampening field. They then beamed the vinculum into space, so that Species 6339 could return it to the debris field to infect more Borg ships. (VOY: "Infinite Regress")
