A young Chinese woman who struggled with balance, dizziness, and slurred speech went to a hospital for treatment, only to discover that she was missing her cerebellum, according to a case study published in the journal Brain.
The 24-year-old is one of nine people diagnosed with cerebellar agenesis, or the total absence of a cerebellum, the study says. The woman reported having problems walking steadily for more than 20 years and, after suffering from nausea and vomiting for a whole month in 2014, decided to go to the hospital.
That’s when doctors reviewed CT and MRI scans and diagnosed her with the extremely rare condition.
According to the woman’s mother, the young woman learned to stand on her own when she was four years old, and began walking on her own at seven years old, albeit with an unsteady gait, the study says. She also reportedly never ran or jumped as a child, and “her speech was not intelligible until six years old.”
The report says the woman has mild mental impairment and medium motor deficits but she’s also married and has a one-year-old daughter. They added that her word comprehension and expression were normal.
The authors noted in the report: “In our case, complete absence of the cerebellum results in only mild to moderate motor deficiency.” They added, “dysarthria [difficulty speaking] and ataxia [coordination problems], although clearly present, were less than would be expected in completely [sic] absence of the cerebellum.”
The cerebellum, also called the “small brain,” makes up 10 percent of the brain but accounts for 50 percent of its neurons, and is responsible for fine motor skills, speech, and balance.
The absence of it, called cerebellum agenesis, is extremely rare. Only about nine living human beings have been recorded to have this condition, and its diagnosis usually occurs by autopsy.