If anybody needs me I’ll be in the cave of frozen memories. 

2x11 Abed’s Uncontrollable Christmas DVD Commentary

Dan Harmon: Every character shares some aspect — is based on an aspect of the writer, eventually. … I’ve been told several times by therapists … my childhood … kind of fried the circuitry in my heart which is why I have trouble with relationships. That’s why [Britta is] a robot. 

2x16 Intermediate Documentary Filmmaking DVD Commentary

Dan Harmon: This is a great exchange. Watch Britta, whose circuitry is unwired. 
Megan Ganz: Her face here.
Dan Harmon: That’s her reacting inappropriately, as Annie points out. … something scarred her, rewired her circuit board and she doesn’t react appropriately. So that’s why she’s the robot in the Christmas episode. She has these behaviours that don’t — there’s overlap there with her and Abed.