How Zombies Brains Work

Regardless to how a Zombie turns, they all act pretty much the same. This is do to whats going on in their brain. Okay a typical Zombie to me, moves slow and stumbles, continually eats even if full, Zombies can see, smell ,and hear, and has no decision making process. Why would a Zombie move slow and stumble about, walking is controlled by the Cerebellum, so knowing that we can conclude that a Zombies Cerebellum is up and running but damaged. Zombies just love to eat and eat, but its not just a love for eating, there's a part in the brain called Ventromedial Hypothalamus which tells you when your full, this is pretty much nonexistent in a Zombies brain. The sense of sight comes from a part of the Occipital lobe, smell comes from a part of the Olfactory bulb, and hearing comes from a part of the Temporal lobe, the lobes themselves don't work just the parts related to those senses. Now why would a Zombies decision making go right out the window, well  problem solving or decision making is controlled by the Frontal lobe and this in a Zombie is completely dead, leaving the zombie with no problem solving or decision making. One last thing that all Zombies have in common is their need to eat living human flesh. I feel that in the cases were a parasite/ bacteria or a virus is the culprit for turning a person into a Zombie that they are the reason Zombies target normal humans. In these cases it could be possible that when the parasite/ bacteria or virus get into the host's brain cells it programs the host to infect and spread so that the parasite/ bacteria or virus can live on and prosper. Since humans have made there way to the top of the food chain these parasites/ bacteria or viruses feel that these are the safest host to be in, so they only program the host to infect other humans. Zombies running on the most basic of instincts can still use it's intact senses to tell the difference between Zombie and human. Sight, can see the difference in speed. Smell, can smell difference in decomposing flesh and living. Hearing, Zombies really don't make alot of noise other than occasional moan and humans tend to yell, knock stuff over, shoot, and lots of other things that Zombies can hear and hone in on. This is what I think makes a typical Zombie tick.