Your brain has been replaced with advanced technologies: Your head can no longer be crippled and is resistant to chem addiction (+25% resistance) and shock from bodily damage (+5% Damage Threshold, minimum +1).”— Fallout: New Vegas description
In the initial dialogue with Dr. Klein as part of the quest Welcome to the Big Empty, you find out that your brain, heart, and spine have been removed and replaced. This perk represents the replacement of your brain. While you technically have these perks from the start of the add-on, they are unlocked in the course of the conversation.
Your head cannot be crippled, you gain 5% DT (with a minimum of +1) and +25% resistance to chem addictions.
- Big Brained does not work correctly. A fix for the PC version is available here. The DT added by this perk and