By Luke Salkeld
As anyone who suffers migraines knows, the pain can leave you speechless. But Sarah Colwill has experienced a much more unusual vocal effect - she now speaks with a Chinese accent.
The disturbing impact of a chronic migraine has left her voice unrecognisable to family and friends.
Doctors say she has Foreign Accent Syndrome, a condition which damages the part of the brain that controls speech and word formation.
It is so rare, there are only 60 recorded cases in the world.
Mrs Colwill, 35, is baffled by the effects and fears she may never regain her normal pronunciation and tone of voice.
She said the change happened after she had such an extreme headache in March that she called for an ambulance.
Paramedics said her voice sounded strange and when she arrived at hospital she realised she was speaking like a Chinese woman.
The IT project manager, who was born in Germany but has lived in Plymouth since she was a child, is having speech therapy to try to revert to her Devon accent.
Mrs Colwill said she had no idea why she had picked up the Far Eastern speech pattern.
"I have never been to China. I just want my own voice back but I don't know if I ever will. I moved to Plymouth when I was 18 months old so I've always spoken like a local.
"But following one attack an ambulance crew said I sounded Chinese. I spoke to my step-daughter on the phone from hospital and she didn't recognise who I was. She said I sounded Chinese.
"Since then I have had my friends hanging up on me because they think I'm a hoax caller.
"I speak in a much higher tone now, my voice is all squeaky. To think I am stuck with this accent is getting me down."
Mrs Colwill has suffered severe headaches for a decade but this year was diagnosed as having rare sporadic hemiplegic migraines.
The condition causes blood vessels in the brain to expand, resulting in stroke-like symptoms such as paralysis on one side of the body.
The effects normally last for around seven days but Mrs Colwill had several migraine attacks at once, culminating with an excruciating attack on March 20 which caused the brain damage.
She has been contacted by Professor John Coleman, a phonetics expert at Oxford University.
He said Foreign Accent Syndrome is thought to be caused by strokes and brain injuries but the condition is so rare there is limited research into why it happens. - Daily Mail