A 24-year-old woman in China just made a shocking discovery: for her entire life, she lived with a hole in her brain where her cerebellum should be.

The cerebellum is thought to control motor function. It may also aid in processing certain emotions like fear and pleasure, and help with language and other things, but the only thing scientists have definite proof of is its role in motor function.

The case was reported in an August 22 issue of the journal Brain. The woman, born with cerebellar agenesis, a condition defined by the complete lack of the cerebellum, went to the hospital because she was experiencing nausea and vomiting. She also reported shaking while walking, and said that she had always been unsteady on her feet, which may have been caused by the absence of the cerebellum.

This case shows that either the cerebellum does not play as crucial a role in motor function as previously thought, or that humans have an astonishing ability to compensate for missing brain functions and develop around them. Some research has indicated that when children or infants are missing part of their brain from a very young age, their body can adapt to the change and compensate for it, rewiring the brain. That might explain how this woman was able to go for so long without even realizing that she was missing an important part of the brain.

"It shows that the young brain tends to be much more flexible or adaptable to abnormalities," said Dr. Raj Narayan, a professor of neurosurgery at North Shore University Hospital in New York. Dr. Narayan did not work on this case.

"When a person is either born with an abnormality or at a very young age loses a particular part of the brain, the rest of the brain tries to reconnect and to compensate for that loss or absence."

There were some abnormalities with this woman that went unnoticed: she did not talk intelligibly until age 6, or walk unassisted until age 7. The girl never went to school. However, for the most part she seems fairly normal. She is a mother now, and gave birth without any trouble. No one else in her family seems to have any neurological damage, the report said.

The world is full of extraordinary cases of people who are missing part of their normal brain function. Oliver Sacks, a neurologist, writes about many interesting cases in his books, such as "The Man Who Mistook His Wife for a Hat."