My giftedness worked against me in one way, in that I often understood things so quickly that I never learned to figure anything out. Especially in grade school, if I didn't get something by just reading it once, I had no idea what to do. I got panicky, as I felt like my powers were vanishing. I don't think I even knew that I was supposed to take concepts apart, or try different approaches. I didn't know there were strategies to figuring things out. And I had no confidence in my ability to do so.

This article about highly-intelligent who lack confidence in their abilities may be of interest:

http://nymag.com/news/features/27840/