The practice of preparing shrunken heads originally had religious significance; shrinking the head of an enemy was believed to harness the spirit of that enemy and compel him to serve the shrinker. It was said to prevent the soul from avenging his death.

What would cause a skull to shrink?

Some amount of brain shrinkage occurs naturally as people age. Other potential causes of brain shrinkage include injury, certain diseases and disorders, infections, and alcohol use. Just as the body ages, so does the brain. But not all brains age the same.

How did headhunters shrink heads?

First, the skin and hair had to be separated from the skull to allow them to shrink at different rates. Then, the eyelids were sewn shut and the mouth was stuck closed with a peg. And for the actual shrinking, the heads were put in a big pot and boiled for a very specific amount of time.