An elderly Chinese woman has woken up after having a stroke unable to speak her native language but fluent in English.
Liu Jieyu, 94, a resident of Hunan province, previously taught English but had not uttered a word of the language for more than 30 years.
Ms Jieyu was admitted to hospital after experiencing what doctors described as a cerebral infarction, which is a type of stroke where the blood supply is limited instead of instantly cut off by a blockage.
When she awoke two weeks later, the retired teacher asked: "Where am I? What is happening?" An English-speaking doctor confirmed she was speaking the language, albeit slowly.
Medic Tao Hou said: "I can't ever remember having a case like this before but we anticipate with proper rehabilitation and rest she should regain the ability to speak Chinese.
"We assume that the area dealing with her ability to speak Chinese has been damaged, but brain cells have an ability to repair themselves to a certain extent, so we would hope to see at least some improvement."
There have been a number of similar cases in which damage to the brain has had an impact on a person's linguistic abilities, the Daily Mail reports.
After being involved in a car accident, Australian Ben McMahon woke from a coma able to speak Mandarin, while a 13-year-old Croatian girl woke up able to speak German rather than her native tongue.
A US navy veteran found unconscious in a motel room with no recollection of his identity woke up speaking fluent Swedish.
Queensland brain scientist Pankaj Shah proposed a possible explanation last year, suggesting that the brain is made up of different circuits involving language, breathing, speaking and thinking.
In the case of Ben McMahon, he stated that the parts of the brain that recalled English were damaged in the crash but those that retained Mandarin were activated when he awoke.
More commonly, people wake up from comas able to speak their native language but with a different accent.
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