The part of the brain that controls vision is at the back of the cereberum, just above the cerebelum, which controls balance.
So, when hitting someone's head, connecting with the back of it is a sound strategy. It is not as protected by the skull as the frontal lobe and causes disturbances in vision, as well as balance.
Actually, in a fight, the best places to hit would be the groin, the solar plexus - as behind the solar plexus is the diaphragm. Bruising it or crushing it will render the opponent unable to breathe, either temporarily or forever - as well as the trachea and the sides of the ribcage, as a broken rib can puncture the lungs, causing death by drowning in your own fluids, or secondary drowning. One emergency treatment is to poke a hole in the collapsed lung and allowing the fluid to be drained from the body, and then re-inflating the lung by blowing into it.
A little bit of knowledge is more dangerous than no knowledge.