| ||For the psychic nullifier that appears in Fallout: New Vegas, see Psychic nullifier (Fallout: New Vegas).|
It is placed on the head of a psyker to disable or prevent them from using their powers. A psychic nullifier also blocks incoming telepathic attacks when worn by a non-psyker, such as those frequently experienced in the Corridor of Revulsion. The Vault Dweller can obtain one to aid in passing through the corridor on the way to the Master.
Gideon and the other three psykers each have nullifiers in the game. The Vault Dweller can kill Gideon or persuade him to give the "helm". The others can be obtained either through theft or killing them.