This is an excellent video that demonstrates the physiological reaction to fight or flight and instincts.
The subject to the trooper's right draws a gun and fires and the trooper avoids being shot, returns fire and eventually wins the fight.
Often, the trooper is criticized for his tactics because he steps between the two vehicles in the illuminated area. However, he reacts in an instinctive manner and as his brain regains control, his tactics improve.
This video is dissected in "Fundamental Body Language" in depth and provides great lessons in our reactions to extreme stimuli.
We will never criticize this trooper.