A developmental disorder on the milder end of the autism spectrum, Asperger's syndrome affects social interaction and communication skills.
As a child, Boyle, now 52, suffered from learning disabilities she was told resulted from oxygen deprivation at birth. A year ago, she sought the advice of a specialist who determined she had an above average IQ.
"I was told I had brain damage. It was the wrong diagnosis when I was a kid," she told the Observer. "I always knew it was an unfair label. Now I have a clearer understanding of what's wrong and I feel relieved and a bit more relaxed about myself."
Boyle became an overnight celebrity in 2009 when her audition for "Britain's Got Talent" went viral. In the clip, the modest church volunteer wowed a skeptical panel of judges, including Simon Cowell, with her rendition of "I Dreamed a Dream" from "Les Misérables." After finishing in second place on the reality competition show, an "emotionally drained and exhausted" Boyle was admitted to the Priory Hospital, a psychiatric clinic in London.
She has since become a top-selling recording artist and also recently appeared in a small role in the religious-themed film "The Christmas Candle."
"It will not make any difference to my life. It's just a condition that I have to live with and work through," Boyle said of her diagnosis. "I think people will treat me better because they will have a much greater understanding of who I am and why I do the things I do."