You say you've met more people that you'd like to remember who just kept making the same mistakes over and over again? There's a reason:
If there is one thing experts on child development agree on, it is that kids learn best when they are allowed to make mistakes and feel the consequences. So Mom and Dad hold back as their toddler tries again and again to cram a round peg into a square hole. They feel her pain as playmates shun her for being pushy, hoping she'll learn to back off. They let their teen stay up too late before a test, hoping a dismal grade will teach her to get a good night's sleep but believing that ordering her to get to bed rightnow will not: kids who experience setbacks rather than having them short-circuited by a controlling parent learn not to repeat the dumb behavior.
But not, it seems, all kids. In about 30 percent, the coils of their DNA carry a glitch, one that leaves their brains with few dopamine receptors, molecules that act as docking ports for one of the neurochemicals that carry our thoughts and emotions. A paucity of dopamine receptors is linked to an inability to avoid self-destructive behavior such as illicit drug use. But the effects spill beyond such extremes. Children with the genetic variant are unable to learn from mistakes. No matter how many tests they blow by partying the night before, the lesson just doesn't sink in.
The discovery, reported last December, is part of what is fast becoming the newest frontier in studies of why children turn out as they do.
Thirty percent sounds about right, although in some places I've been I'd have sworn it was a lot higher. New favorite insult for the blogosphere: You, sir, are a