The effects of environmental factors on change in IQ have been a major concern to experts. Previous analysis' on IQ changes and factors that contribute to change in IQ, indicate that it is tangible but doesn't touch on how the changes may occur. This article demonstrates a number of environmental and demographic factors that may effect IQ and its change over time. The analysis records data from 1,746 students at a school in Pittsburgh. They record and document IQ scores at kindergarten, fourth, sixth and eighth grades. I find it interesting, because the article states that the results indicate that the number of parents living in the household has a positive, important effect on IQ at the earlier age, or kindergarten stage. I also find it interesting that they say a negative effect on IQ is the number of siblings the subject has. The results show that females show faster development up until fourth grade, but that difference in male and female IQ scores begins to fade around eighth grade. It is concluded that a main influence on the development of IQ are the "socioeconomic status" of the student's parents and peers in school, with the status of their peers being the more important.
The way the test was conducted began with 3,762 children who took at least one IQ test, of which 2,067 took all four tests. The groups are divided by children assigned to special education classes, and children who've moved into the school system. This is because children assigned to special education classes are typically not given IQ tests, and children who've lived else where have been exposed to various cultural influence, as opposed to a student who's stayed in a school system their entire education.
It is then taken into account and measured, the number of siblings and parents living in the household as well as the socioeconomic status of their parents.
The article states that although sex, and the number of people living in the household have both a positive and negative effect at a young age, the predominant influence on the development of IQ are the socioeconomic status the family has next to their peers at school.
The article then goes into further detail on the various tests and locations preformed as well as the details and logistics of each one.
I think it's interesting to think about development of IQ over an extended period of time because we typically don't think about how it may come about or what factors may contribute to development. I'd assume from personal experience that someone who is raised in a wealthier, less stressful and economically stable environment will naturally develop a higher IQ as opposed to a child who may have grown up in a less fortunate situation. I also believe that IQ is something that comes naturally, regardless of the upbringing of the child. Although many factors definitely contribute to the changes and development, some children are naturally more inclined than others. I believe it's embedded in our DNA and most factors can't have a dramatic or drastic influence on IQ.