Author Susan Cain, a self-described introvert, accepted an invitation to do what she feared — give a TED talk. Although she was anxious on the big day, she got through it and wowed the audience.

MONTEREY, Calif.--If you sense numbers as colors, or see images when hearing a tone, you might be a poet and not know it. Atypical and subjective responses to colors, sounds, numbers and the like are ...