The very notion flies in the face of conventional wisdom. Most people presume that no matter how hard they work, they are not going to get any smarter. Some subjects in our research laboratory, though, have increased their IQ scores after training their brain for as little as three weeks. The improvement can be significant enough that, anecdotally at least, a few participants
noticed a difference in their daily activities. One individual, for example, reported sharper chess skills, stating, “I can plan further ahead.” Another said that it felt easier to sight-read music while playing the piano.
How is this possible? Researchers have long believed that fluid intelligence—which reflects how well you tackle a new task rather than what facts you possess—is a fixed attribute, directly inherited or acquired very early in life. Indeed, evidence shows that fluid intelligence, as with height, is highly heritable, by some estimates as much as 50 to 80 percent. Yet intelligence can still be honed. Just as nutrition can influence height, environmental variables can also either brighten or beleaguer minds. Consider the Flynn effect: over at least the past 65 years measured intelligence, such as scores on the SAT, has steadily increased even though the genetic constitution of the population has not changed measurably.