In the 1940’s, psychologist Raymond B. Cattell attempted to create “culture-free” tests of intelligence. Believing that IQ tests contain implicit biases in favor of particular cultures, he sought to partition intelligence into two components–fluid and crystallized. He described fluid intelligence as “a capacity to perceive relations and educe correlates.” In essence, this is the capacity for new conceptual learning, abstraction, and problem solving and is measured by relatively culture-free “IQ tests” such as Raven’s Progressive Matrices. In contrast, crystallized intelligence is that part of intelligence that has grown out of acquired intellectual skills and distilled from learning experiences. Cattell defined crystallized intelligence as “cognitive performance in which skilled judgment habits have become crystallized as the result of earlier learning application of some prior, more fundamental general ability to these fields.”
For example, a child’s proficiency at the game of tic-tac-toe would be mainly a measure of her fluid intelligence, if she had just learned the game; however, if she had played enough to learn the importance of occupying the center and corner squares, her proficiency could derive from this acquired (crystallized) knowledge. When we operate machines and computers, we begin to assimilate these skills into our inventory of knowledge–stored in our brains as crystallized knowledge. When we work on computers over a prolonged period of time, we begin to acquire a familiarity with computers and we become “computer literate.” The issue at the heart of your question is, “How transferable to IQ is this newly acquired crystallized intelligence?”
From the early 1930s and beyond, IQ tests were periodically restandardized. This meant that the researchers had to administer the IQ tests to a large number of people and set the average performance at 100. However, it was discovered that people were achieving scores substantially higher than 100 on the same IQ tests as those involved in the earlier standardization. This upward drift in IQ of about one standard deviation (15 points) every two generations is now known as the Flynn effect, in recognition of James R. Flynn’s discussion of its potential causes and implications.
In his TED Talk, presented on September 26, 2013, Flynn hypothesized that the new technologies including radio, television, and computers are demanding more abstract thought than the environment of the early 20th century. He noted that in 1900, only 3% of jobs were cognitively demanding, including occupations such as doctor, lawyer, teacher, and accountant. He compared this to the 35% of jobs today that demand higher order thinking skills. Flynn asserted that the high-tech environment is stimulating a latent capacity for abstract thought that was not as strongly demanded in previous generations.
The rapid increase in IQ in two generations is too fast to be attributed to genetic mutation and suggests that intelligence can be increased by appropriate environmental influences. In fact, research in the newly emerging field of epigenetics is revealing that environmental influences can “switch on” and “switch off” certain genes, while research in neuroplasticity has shown how the brain, after suffering injury, can “rewire” its synaptic connections.
Though more research is needed, it is becoming clear that intelligence interacts with the environment in such a way that it can be altered significantly, though we don’t yet know the limits of such changes.
