Savant syndrome comes in different forms. In congenital savant syndrome the extraordinary savant ability surfaces in early childhood. In acquired savant syndrome astonishing new abilities, typically in music, art or mathematics, appear unexpectedly in ordinary persons after a head injury, stroke or other central nervous system (CNS) incident where no such abilities or interests were present pre-incident.
But in sudden savant syndrome an ordinary person with no such prior interest or ability and no precipitating injury or other CNS incident has an unanticipated, spontaneous epiphanylike moment where the rules and intricacies of music, art or mathematics, for example, are experienced and revealed, producing almost instantaneous giftedness and ability in the affected area of skill sets. …technically sudden savant syndrome would be better termed sudden genius.
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Many people pick up a new skill or hobby, especially later in life. So what is different here?
—The skill has an abrupt onset with no prior interest in or talent for the newly acquired ability.
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—The new skill is accompanied with an obsessive-compulsive (OCD) component; there is the overpowering need to play music, draw or compute. …
—There is a fear the gift and OCD is evidence of losing one’s mind, and a tendency to hide the new ability from others rather than display it.
Read full, original post: Brain Gain: A Person Can Instantly Blossom into a Savant–and No One Knows Why