io9 interviews Jake Gyllenhaal for Source Code interviews Jake Gyllenhaal for Source Code

-"Did you study the science behind the film?
-Gyllenhaal: Particularly my job is more about, what would be the emotional effects of something like this? What would it be like if I found myself there. If I had a background in the army and in flying helicopters. If I was put in this situation, how would I respond? To me it was the human behavior aspect of it that I was fascinated with.
Duncan sent me lots of different videos. And one of them was pilots in pilot traininf school, when they do G-force training. And their responses to the first time they go into G-force, because they have a simulator that they go into. It's actually relatively funny, because a lot of them lose consciousness, and then come to and don't know what happened. That's what I was into. This is a similar experience. When he wakes up at first (and I don't know if this is in the final version of the movie) but we did say, the first time, "Did I A-lock?" which is a common response when you lose consciousness when you go into G-force. He comes to and he's like "whoa am I just tripping out am I hallucinating did my helicopter go down?" Nope, you're on a train sitting next to a woman saying she knows you and you have no idea who she is. And you're in somebody else's body". Source: