Many scientists have concluded that brain training can increase your performance on an IQ test. But scientists disagree about whether this means you've grown smarter. For one thing, it's widely acknowledged in the 21st century that IQ tests don't test native intelligence; they test only your ability to take tests. Your results depend upon education and training. Nevertheless, some highly respected scientists believe that brain training can have profound results. Your ability to score higher on an IQ test may be the least of it.

The View That IQ Can't Be Changed

In the 20th century, there was an enduring belief that IQ couldn't be changed. In the 21st century, however, interest in brain training that purports to make positive IQ changes relatively quickly is increasing. Academics have known this for a long time. In a speech given in 1967 before the California Advisory Council of Educational Research, Arthur Jensen, a University of California psychologist, reported extensive research showing that IQ wasn't absolute but was affected by the postnatal environment. Things could be done to raise it, he proved. Despite this, only in this century have programs become widely available to help you raise your IQ. One reason for the lack of interest is evidenced in Jensen's own conclusions, which were that biology -- the brain you were born with -- was such an important component of IQ that although IQ could be changed, it probably wasn't worth the effort.

What IQ Tests Test

Whether or not you can really change your native intelligence -- the biological capabilities of your brain -- isn't relevant when considering whether you can raise your IQ, which usually means raising your IQ test results. It's now generally conceded among research psychologists and others working in the field that IQ tests do not test intelligence. They test your ability to do well on an IQ test, which tests developed skills.

Fluid Intelligence vs. Crystallized Intelligence

A modification of the view that your IQ can't be changed is the idea that one kind of intelligence -- crystallized intelligence -- actually grows with age, but that another, fluid intelligence, peaks early in life and can't be changed. Scholars have understood that crystallized intelligence can be increased through learning but had assumed that fluid intelligence, assumed to be more closely related to the inherent capability of the brain, was incapable of improvement. However, according to a 2012 "New York Times" article, 2008 research by Susanne Jaeggi and Martin Buschkuehl demonstrated that specific training methods can actually increase fluid intelligence. Subsequent studies demonstrated that this kind of training is not just task specific; certain kinds of brain training result in broad improvements in working memory and other capabilities. As of this writing, a variety of brain-training programs are widely available on the Internet and elsewhere.

Skepticism Remains

Many highly regarded scientists are enthusiastic about brain training and its future, especially for populations with specific problems, such as attention deficit hyperactivity disorder. Others remain skeptical. The skepticism takes two forms. Some scientists acknowledge the usefulness of brain training but object to trendy programs that over-promise their results. Others, like Randall Engle, a leading research scientist at the Georgia Tech School of Psychology, is quoted in the "New York Times" article as remaining highly skeptical of the basic premise.