In Star Trek: Voyager, the Borg vinculum coordinates the thoughts and activities of drones in a collective.
The vinculum is a specialized Borg device that links the neural activity of drones and helps organize information within a Borg vessel. It acts as a central processing and coordination point, filtering individual signals into a unified collective consciousness.
Voyager explores the device in “Infinite Regress,” when Seven of Nine is affected by a vinculum recovered from a damaged Borg vessel. The story demonstrates that the technology can carry traumatic or conflicting neural patterns, causing Seven to experience multiple personalities associated with species assimilated by the Borg.
The vinculum is not the same thing as a Borg implant, cortical node, or alcove. Individual drones have implanted hardware, while the vinculum serves a larger communal function aboard a Borg ship. Its name comes from the Latin word for a bond or connection.