In the original Blade Runner, the Voight-Kamp…

In the original Blade Runner, the Voight-Kampff method was used to distinguish Replicants from humans. In this film, a more advanced technology analyses a Replicant’s operational stability. “The Baseline is designed to test the effects of a Blade Runner’s job on his brain and psyche.”
Explains Ryan Gosling. “Because they have to kill their own kind, they constantly need to be assessed as to whether their work is having some kind of impact on them.” 

Two versions of the Baseline scene were filmed for the movie: the original scripted version, and a much longer take written by Ryan Gosling himself.
It was a lengthy eight-minute staccato dialogue, and Gosling delivered each take without hesitation for every camera angle.
The moment it was filmed, everyone on set felt that they had witnessed something unique and powerful. “When you are shooting a movie, there’s always a scene that makes you feel you’ve made contact with the soul of the story,” recalls Villeneuve. “That was it, and it became our own Baseline for the rest of principal photography.” 

This feeling was shared by Joe Walker in editorial, “it was one of those great times as an editor, where you lift off from the page and it’s no longer about the scripted material, but there is blood running through the veins of an idea.” The long scene was later fine tuned to serve its percussive purpose in the final cut. “It’s an attack on K’s psyche, so it has to wrong foot him and be hellishly aggressive. That gave me a lot of material to work with rhythmically in the cut”

From the Art and Soul of Blade Runner 2049