We have all gotten angry at one time or another. We have screamed, we have thrown all kinds of curses, the vein in our foreheads has become very fat. But why? What are the evolutionary roots of this behavior? What good has it been that our ancestors got angry the way we do?
Apparently, the fastest way for our brain to change our surroundings (that is, what makes us angry) is emotion.
When we get angry, as the studies of Charles Carver and Eddie Harmon-Jones with brain scans point out, activity in the obitofrontal cortex is increased, a region of the brain normally related to the control of emotions and goal-oriented behavior.
This is all very well, but does anger serve a physiological level?

Apparently, yes, as is clear from the studies carried out by Miguel Kazén and his collaborators at the University of Osnabrück: worries or threats cause us stress, but the anger we experience when we get angry reduces our cortisol levels, the stress hormone, which in turn decreased the potential damage caused by stress.
Dean Burnett offers a possible explanation for this paradoxical observation in his book The Idiot Brain , alluding to the fact that certain studies suggest that anger produces increased activity in the left cerebral hemisphere, in the anterior cingulate cortex and the frontal cortex:
These are regions associated with the production of motivation and reactive behaviors. They are present in both hemispheres of the brain, but perform different tasks in each of them; In the right hemisphere, they produce negative, avoidant or withdrawn reactions to unpleasant things, while in the left, they generate positive, active, approaching behaviors.
That is, one part of our brain says "run away, go back, hide yourself" and the other part says: "I’m not going to take this anymore, we have to remedy it":
It is more likely that, in people who have a more extroverted personality and who feel more self-confident, the left bond is the dominant one, while in those of the more neurotic or introverted type, the right one is the dominant one.