kraftiekortie wrote:
There's too much emphasis placed on "genes," not enough on the environment.
In this case, I would accept that "genes" PREDISPOSES one to things such as "low nonverbal IQ." However, though I had a borderline nonverbal IQ as a 15 year old adolescent, I was able to achieve, consistently, an average nonverbal IQ in adulthood--through life experience and the use of my cognitive faculties.
Actually, the data suggests that environment affects the IQ of children more strongly than adults. So it may be that your low nonverbal IQ at 15 was environmentally induced, and you've since reached your genetic potential.
Also, sometimes your genes and environment are correlated. For example, one trait associated with IQ is 'need for cognition' - a personality trait where a person enjoys and seeks out mental challenges. Let's imagine need for cognition has a genetic component. (I don't know if it does or not, the research hasn't been done.) A person with high need for cognition would be more likely to give themselves plenty of mental 'exercise', and end up maximizing their genetic potential for IQ. Someone with low need for cognition, meanwhile, would avoid mental exercise whenever they can, and therefore not reach their full potential. This is especially true in adulthood, because children have a lot less choice about their opportunities for mental exercise.