This is most likely not a practical effect. In order to achieve this effect practically, one would need a light that is sync'd to the frame rate of the camera to turn on for 1/24 (depending on the framerate) of a second. It sounds...impractical (word jokes!).
You can easily isolate a frame in After Effects by converting you time line to frame rate time signature as opposed to seconds.
Alternatively, you can use the hotkey (ctrl + right/left arrow) to create an animated color correction to do whatever you want. In this case, you would find the brightness/contrast effect, place it on your footage, press the animation icon on the effect, go to the spot you want to be bright, ctrl+right arrow back one frame, create a key frame, crtl+left arrow two frames forward, and create another key frame. You back up one keyframe to where you want the effect to be, crank the brightness and bang, your effect is done. Quite simple.
To answer your question about RAW, it was likely shot in RAW, but that has no impact on how this effect was achieved. You can do the same with heavily compressed h.264 footage.