Why has it take 40 years to discover how to improve IQ?

Back in the 1950s, Professor Jensen - a leading authority on intelligence - concluded that nothing could be done to improve our IQ level - that it was fixed from early childhood. This was the scientific consensus. Numerous studies investigating the effect of different types of cognitive training over the past 40 years have not done much to change this view - that is, until 2008 when a team of cognitive psychologists from Bern, Switzerland and Michigan, United States, demonstrated that a very specific type of cognitive training can improve IQ dramatically.

Why has it take 40 years to discover how to improve IQ?

It is only thanks to recent insights from cognitive psychology about the nature of short term memory and its importance in cognitive functioning have at last enabled a training exercise to be engineered that improves IQ. As cognitive psychologists, we have now uncovered many underlying information processing systems of intelligence. It is this understanding that has enabled us to design the task to be effective to improve intelligence, regardless of starting IQ level. We will now look at how these mechanisms work.

We can improve IQ, but how does it work?

Our short term memory is a big part of the story. We use our short term memory all the time for any storage of information that is short term - perhaps over a matter of 10 or 20 seconds - for example, while remembering directions have have just heard while driving.

The Magical Number 7

The amount of information most people can hold in short term memory (numbers, food items, directions) is limited to around 7 items - plus or minus 2. This short term memory capacity or 'memory span' has been called the 'magical number seven' in one of the most famous papers in cognitive psychology, by George Miller at Princeton University.

Working memory

But more important than just remembering information by rote is being able to do mental operations on that information - to solve a problem, to figure something out, or reason through something to find an answer. For instance, while figuring out a 15% tip, or how much currency is worth while you are in another country. The ability to hold information in mind for brief periods, and manipulate it mentally is a type of short term memory called working memory. You have to do mental work on the information, not just store it. That is why it is called 'working memory'.

The capacity of working memory

Most people have a working memory capacity of about 2 or 3 - much less than the memory span of the 'magical number 7' for just storing information without doing any cognitive operations on it.

The working memory-IQ link

People vary widely in their working memory capacity. Ä°t is now known that these differences predict IQ level. General intelligence - measured by standardized IQ tests - depends on working memory because working memory affects a wide range of complex cognitive tasks besides figuring out a tip, involving reasoning problem solving, and making sense of things. We use working memory every single time we reason, plan and problem solve. Even comprehending long sentences (like the ones in this article) requires working memory!

Working memory and the intelligence behind our IQ level both share the same brain circuitry - part of the frontal cortex of the brain called the dorsolateral prefrontal cortex. ('Dorsal' means up, and 'lateral' means to the side - hence 'dorsolateral'). This is one of the most recently evolved parts of the brain.

How to improve IQ - the logic

The logic is simple: If you can improve your working memory capacity by training it directly, you can therefore improve your intelligence level. There is, in technical terms, a 'transfer effect' from working memory training to gains in intelligence and IQ.

Intelligence can now be improved by 40% - as a side effect.

In 2008 cognitive psychologists at the University of Be in Switzerland and the University of Michigan in the States, demonstrated that by training on a specifically designed working memory exercise you can increase working memory capacity by over 65% over just 19 days of training.

This improvement in this type of short term memory capacity had a remarkable side effect: a 40% gain in intelligence - as measured by a version of the time limited Raven's Advanced Progressive Matrices IQ test - one of the most valid and highly regarded IQ tests for culture fair intelligence.