Very interesting book on violence & martial arts: Meditations on Violence: A Comparison of Martial Arts Training and Real World Violence
“…Under the stress hormones, peripheral vision is lost and there is physical “tunnel vision.” Depth perception is lost or altered, resulting in officers remembering a threat five feet away as down a forty-foot corridor. Auditory exclusion occurs–you may not hear gunfire, or people shouting your name or sirens.
Blood is pooled in the internal organs, drawn away from the limbs. Your legs and arms may feel weak and cold and clumsy. You may not be able to feel your fingers and you will not be able to use “fine motor skills,” the precision grips and strikes necessary for some styles such as Aikido”