Why are Headwounds the Traditional Weakness of Zombies?

In the zombie universe, it was always a bit of a problem describing the exact process of zombification because of 2 schools of thought; 1) the scientists that attributed the phenomena to a microscopic brain controlling parasite or unusual radiation capable of reanimating the brain, and 2) those that believed that it was a supernatural event, attributed to voodoo, black magic, satanic curse, God's wrath, etc.

If there's a scientific explanation, then parasitical activity could very well spread throughout the entire host, with the organisms actually supplying the functions needed for movement. If radiation, then perhaps the brain can actually continue controlling the body but only for a short period as rapid decomposition sets in (probably harder to believe).

As far as supernatural causes if this was the case, then everything above is moot and the head might just be the focal point where the supernatural activity is centered. Perhaps destroying the head dissipates the energy that is creating motor movement, who knows?

Wish I knew more but all I know is what little I've read about and seen in the movies. Btw, thanks for your post, that was an interesting question and I'm sure there are those working on a believable, more rational explanation.

It's covered in Zombie Survival Guide by Max Brooks, writer of WW Z. Find it. If you're a WWZ fan, you'll like it.
Don't recall the details, but somehow the bodily functions are totally reworked when infected. The body doesn't decay in the normal sense. The flesh is toxic and immune to any organisms bacteria/maggots that would facilitate decay. It's like flesh soaked in formaldahyde (sp?).

You will find countless explanations how Zombies in movies like "World War Z" or "The Walking Dead" work.



But the actual answer is "magic", because those Zombies defy all laws of nature.