The item is in the engine room of the Duchess Gambit, on the table next to Tobar. It can only be obtained after completing the quest Walking with Spirits and asking Nadine in the Ark & Dove cathedral to remove the player character's scar.
- Taking it may have originally been intended to reward the player character with the removed Gray Matters perk.
- It appears that the player character had significantly less brain taken out than most of the quantities in the other jars that can be observed; this might be why the player character isn't affected by the lobotomy like the tribals. There is also no change to any of Lone Wanderer's stats or skills.
- Upon examining this item, the game states that "you feel a terrible sense of loss" when looking at this familiar piece of gray matter. This is a direct reference to Fallout 2's mutated toe. However, there is no option to eat your lump of brain in Fallout 3 as there was in Fallout 2 with your mutated toe.
- The 'familiar' piece of brain will be on the Duchess Gambit even before you start the quest. On the PC version, you can unlock the door with console commands and find it.