MISSING: Cerebellum!

A woman, age 24, was admitted to hospital in China after complaining of dizziness and nausea, only to find she had part of her brain missing. Her mother reported she had not walked until age 7 and she had not been able to walk steadily her whole life. A CAT scan revealed that she had no cerebellum and that the space was instead filled with cerebrospinal fluid.

Top image: Normal brain showing cerebellum (http://myweb.tiscali.co.uk/ataxia.pages/)

Bottom image: Brain missing cerebellum (Feng Yu et al.)

The cerebellum modifies motor commands in order to maintain balance and posture, coordinate voluntary movements, and it plays a part in motor learning and cognitive functions. Although it represents 10% of the brain’s total volume, it contains 50% of its neurons.

Only a few are known to have lived without the entire cerebellum, but it usually causes severe mental impairment, motor disorders or epilepsy. However, this woman only had a moderate motor deficiency, and despite her speech only becoming understandable at age 7, she only had mild speech problems.

The doctors suggest that normal cerebellar function may have been taken over by the cortex, showing how plastic the brain is, being able to compensate for such an important part.