When at war there is no time for error or hesitation that is commonly found in human behavior. There is no room to freeze when being shot at. When someone starts attacking you it is pertinent that you automatically find out what is going on and begin your plan of attack. Because this is not normally how one would respond, this behavior has to be trained. The military uses a role model, I.E. the drill Sergeant that all recruits look up to and aspire to be. They will begin to mimic his movements and behaviors that will make them better suited in war. They also train in highly stimulating environments with life like targets. For example they may train with lots of screaming, gunshots, explosions, etc. and have to shot at human shaped targets so that they become desensitize to the noise and are able to think under pressure. This training rewires their brain and the soldier no longer has normal responses to these types of situations. They now perform better under pressure and are more likely to succeed in their mission.