Childhood and adolescence spent waiting for others to catch up was excruciating, but adulthood has been a disappointment, too, because I never considered the fact that while I was "waiting" for them, I was not standing still either.
And there's a flip side: in a certain sense, NT people mature too quickly for a PG kid. Biologically speaking, brain maturation means ending the period of massive learning, creativity, and exploration and becoming a "finished product" i.e. an adult. Some species have longer periods of juvenile flexibility than others, and humans are at one extreme, retaining features of mental juvenility throughout the lifetime.
But PG people are at an extreme of that extreme. In addition to what HK describes of being ahead of my peers, I also experienced other kids being too quick to leave the interesting parts of childhood behind. When we hit junior high, play, invention, and mental exploration seemed to shut off like a spigot, and one was supposed to just "hang around." Complaining about being bored was a popular pastime. So was sunbathing (this was the '70's), which made me want to chew my own hind leg off.
The concept of "mental age" as a way to understand gifted development is a myth. It's not "ahead" or "behind." It's qualitatively different.
