Scientists Can’t Find Specific Genes for IQ
Recent research has shown that, while intelligence is believed to be partly genetic, the specific genes that were thought to be linked to intelligence are not. And, in fact, of all the genes that were examined, only one was actually associated with intelligence and the effect was very small.
While Science Daily characterizes this discovery as “surprising,” it shouldn’t be a surprise at all. First, the growing body of research makes it clear that intelligence is modifiable — that it develops as the brain interacts with the environment. And second, it is becoming increasingly clear that intelligence is not a single thing. Some scientists continue to insist that there is one factor they call “g” that is overall intelligence, but other research is making it clear that intelligence is really many mental processes that operate independently and interactively.
Consider, for example, Howard Gardner’s multiple intelligences, or George McCloskey’s extensive list of executive functions, or the array of cognitive processes that are developed in BrainWare Safari. Skills like Working Memory have been shown to be highly correlated with measures of intelligence. Mental processes like Inhibition are associated with social and emotional intelligence. And Visualization is connected with reading comprehension. Those are just a few examples. And we also know that those skills can be measured independently. Yet they must all work together to produce actions, thoughts and decisions that are suited to one’s environment.
The role of the environment is key. Intelligence is generally held to be intelligence because it allows us to adapt to our environment, to be flexible in how we interact with it (others and the physical world). As the environment changes, the skills we need to draw on are different. Some environments require the ability to sustain our attention; others to divide it. Holding information in short-term memory is different from getting it stored in long-term memory. Visual discrimination and auditory discrimination are different. But all these skills play a role in our ability to be effective in interacting with our environment, and hence a role in intelligence.
Not only is this new research not surprising, it is entirely consistent with what other scientific disciplines, such as cognitive neuroscience are telling us about the brain and intelligence.