The Brain (Point Lookout)

 was one of the inhabitants of Point Lookout and a member of the prestigious Calvert family before the Great War. He survived the war by extracting his brain out of his body and preserving it in the Underground Lab thanks to experimental robobrain technologies. This has allowed him to survive for over 200 years and, thanks to this experiment, develop psychic powers which allow him to communicate with other people as a "voice in the head". He has a long-term rivalry with Desmond Lockheart, who apparently battled him many times before the Lone Wanderer arrived and even managed to create (or find) a device which blocks the Professor's psychic abilities.

The battle of the two rivals continues as professor becomes a "god" to a local tribal cult. He communicates with the outside world thanks to his robots and as a hologram. He uses the cult as his own agents, however the cult, due to their religious fervor and mental impairments, frequently misunderstand him leaving him very frustrated. When the tribals fail to kill Desmond and destroy the device which jamms the professor's abilities, he learns (by psychically contacting the mind of Lone Wanderer) that the jamming device is ready to be installed on the top of the ferris wheel to completely ban his powers. Calvert contacts the Lone Wanderer, appering as a voice in the head, and asks him to stop, and instead of fighting him destroy the device and kill his arch rival Desmond.

No matter which side of the conflict the Lone Wandered chooses, he is forced to kill Professor Calvert at the end of the Meeting of the Minds quest. With his death, the people of Point Lookout and the Capital Wasteland (and probably from much farther locations too) are safe from his mind-entering psychical powers.

Abilities
Professor Calvert is technically a human brain in a jar. He speaks in a rapid-fire voice and tends to refer to himself in the third person. He posses an ability to control his robots (due to both psychic power and being a part of the lab systems) and could access minds of other people from the great distance. His psychic powers are strong, but are limited by the jamming device in possession of Desmond Lockheart. He still able to communicate to people not far from his location. He also controls a local tribal cult thanks to his psychic abilities and a holographic projector he entrusted to Jackson, the cult leader.

Bugs

 * There is a common glitch where the player will randomly be informed that The Brain is unconscious whenever they go near the boardwalk. This is because Proffersor Calvert's actual actor, named The Brain, resides in an unopenable Pulowski Preservation Shelter hidden in the soda shop neighbouring the The Homestead Motel, and is possibly falling through the map and being knocked out due to falling damage.
 * If you go to the area around the Ferris Wheel you will notice a green dot on the radar to the right of the ferris wheel, indicating a friendly NPC, The Brain. He can be reached by the player although no conversation may be started with him and he has the cloak effect similar to that given by a Stealth Boy. The following is how to reach The Brain:
 * On the 360 version of the game this area is is reachable by use of stacked baby carriages, or jumping from the truck on the opposite side of House of Wares to the rooftops and jumping rooftops till you get there. Upon getting on and falling through the roof, you can find this hidden occupied Pulowski Preservation Shelter with The Brain in it. However, it cannot be opened. It is most likely here for when he talks to you during the quest Thought Control.
 * PC players can simply use the command to travel through the walls and reach the Pulowski Preservation Shelter with The Brain inside.

Trivia

 * The French movie "The City of Lost Children" features a professor named Krank who lives in a far-away lighthouse. He orders his minions to kidnap children, so that he can steal their dreams. His arch-nemesis is a professor named Irvin, who appears as a human brain in a bubbling water tank.
 * His appearance and role as an antagonist reminds of both the Calculator and Simon Barnaky. All of these characters were cybernetically preserved human brains.

Appearances
appears only in the Fallout 3 add-on Point Lookout.