Violetta's brain is a miscellaneous item in Fallout: New Vegas.
Characteristics
It is one of three possible replacement brains for the companion Rex during the quest Nothin' But a Hound Dog. If this is used as the replacement brain for Rex, he will have an increase in movement speed. Other dropped dog brains are Rey's brain and Lupa's brain.
Location
It is found on the dead body of Violetta, one of Violet's guard dogs during the quest, Three-Card Bounty.