There are two major errors that we make when we think about ourselves and the origins of our attitudes and behavior. One error is the myth that human development from conception to adulthood is a shielded process predetermined by genetics, and the second error is the myth that if development is indeed malleable social change has only a minor effect.
The psychologist Patricia M. Greenfield (University of California Los Angeles) has now given us an important theoretical analysis of how the extended groups we live in ("sociodemographic ecologies") alter cultural values and learning environments--and thereby shift development pathways. (Developmental Psychology, 2009 45(2):401-418.
At the neurological level, "development" of course means wiring of the brain, a process we know is not complete until at least adolescence. Psychologists focus on "learning" during development, but neuroscientists have their eyes on the brain as a changeable and changing tissue.
Greenfield points out that worldwide sociodemographic trends include movement from (A) rural residence, informal education at home, subsistence economy, and low-technology environments to (B) urban residence, formal schooling, commerce, and high-technology environments.
As Greenfield tells us, empirical research shows that the trend from (A) to (B) shifts cultural values in an individualistic direction, and shifts developmental pathways towards more independent social behavior and more abstract cognition.
In plain language, what this means is that when any group, community, society moves from conditions of (A) to conditions of (B) as given above, we can expect important changes in psychological development--an effective reshaping of behavior and intelligence.
In even plainer language, since IQ is a measure of abstract cognition, if a non-industrial society gets industrialized, we can expect that within a short time the average IQ of its school children will increase.
There's no reason to be shocked by this. The reality has been hanging over us for some time, acutely configured by the Flynn Effect, the observed increase in IQ from one generation to the next, especially in developing countries.
The construction of an IQ test involves a normalization process. Items in the test are selected and included so that a sample population will produce a symmetrical bell-shaped distribution of test scores with a mean and median of 100 points and a standard deviation of 15 points. The test is renormalized at intervals of 20 or 25 years to keep the parameters of the distribution curve the same: mean and median of 100 points and standard deviation of 15 points.
In the 1980s it was discovered that the renormalizations of the Stanford-Binet IQ test, ongoing since its introduction in America in 1932, and the renormalizations of the other major IQ test, the Wechsler Adult Intelligence Scale (WAIS), ongoing since 1953, had been hiding the fact that the performance of the American population on IQ tests had been increasing about 3 points per decade or approximately 10 points per generation.
This is the Flynn effect, named after James R. Flynn, the New Zealand psychologist who first brought the phenomenon to everyone's attention. Within a few years it was further discovered that the effect is also occurring in 14 nations around the world. The number of nations has now grown to 23.
The 23 nations that have shown massive gains in IQ are as follows: Argentina, Australia, Austria, Belgium, Brazil, Canada, Denmark, Dominica, Estonia, France, Germany, Great Britain, India, Israel, Japan, Kenya, Netherlands, New Zealand, Norway, Spain, Sweden, Switzerland, United States.
The first study to document the Flynn effect in a rural area of a developing country (Kenya) was reported in 2003. From 1984 to 1998, the Raven's IQ score in that rural district increased 4.5 points. The Raven's (known as Raven's Standard Progressive Matrices) is a widely-used, mainly culture-free, IQ test involving analogies of geometric shapes. Results from a study on the Caribbean island of Dominica were reported in 2005. In this study a Flynn-effect increase in Raven's IQ score of 17 to 19 points apparently occurred over a period of 37 years.
It's probable that sooner or later every nation in the world will be included in the list of countries where massive gains in IQ are apparent from one generation to the next. No one knows why this is happening, but I will bet that when the explanation arrives it will have been anticipated by Greenfield's analysis of the effects of social change on human development and abstract cognition.
Coda: There's a reason why your 10-year-old daughter is more facile with computerized gadgets than you are: her brain is wired up differently than yours, and that's a result of cultural change.
(Note: The paragraphs on the Flynn Effect above have been lifted from my book, More Than Genes, Oxford University Press, October, 2009.)