Matrices Problems In Mensa’s IQ tests

Try the examples 24 and 26 below from Mensa’s IQ workout, which can be found on the Mensa International website. These are called ‘matrices’ problems. Some Mensa qualifying tests only use matrices problems.

To help us understand the elements of this skill set, take question 26 in the Mensa workout. Notice the line in the bottom left corner and ignore the other stuff; in the next square it’s in the top right corner, then it’s back to the bottom left, then up again to the top right and so on. There’s a pattern. So you can reason that the answer has to be b or c. Hold that in mind. Now look at the bottom right corner line. Next square there are two lines in the top left, next box there are three lines bottom right, next box four lines top left, then five bottom right. So the next has to be? Six lines top left. Only a and c show this. From before, we know that it can’t be a. So we can conclude right there – without even looking at the other lines in the box, that the answer is c.

To solve this kind of problem we need to use what cognitive psychologists and neuroscientists called executive processes. With executive processes we can’t rely on an automatic response based on past experience to solve a problem – we have to reason it through with full attention.

Executive processes – elements

Here they are

  • We have to selectively attend to some information and ignore distracting information.
  • We have to hold items of information in short term memory (what is known as ‘working’ memory’).
  • We have to do mental operations on the information  (e.g. ‘add one’) and update the information we are attending to as we are working through the problem.
  • We also have to break the problem down into sub-tasks  and be strategic with our effort in different sub tasks. For  instance, there was another sub-task we could have done – looking at the other set of lines – but we didn’t have to look at them. This involves monitoring how we’re doing on the task by observing how our own mental processes work.

All these cognitive skills are the elements of executive processes. They lie at the heart of the ‘brain power’ aspect of what IQ tests measure. If a person  is good at  doing these things, the have more brain power.  And they will do well on the matrices sections of an IQ test.

The very good news is that our IQ can be increased  not only by improving by practicing these problems – there is a BIG practice effect for all IQ test questions – but also by training our executive processes. By training our executive processes we actually increase our fluid intelligence and brain power. We become ‘smarter’ in the most basic sense – better able to process any kind of information, and solve any kind of problem, not just ones we have prior knowledge about.

Improve IQ by training executive processes

In 2008 brain scientists at the University of Bern in Switzerland and the University of Michigan in the States, demonstrated that training on a carefully designed exercise that directly trains these working memory elements,  resulted in a remarkable gain in fluid intelligence as measured by a version of the time limited Raven’s Advanced Progressive Matrices test – a test with questions just like the ones above.


Enter your email for direct delivery of new articles:


I am a cognitive scientist with a joint Ph.D in cognitive psychology and neuroscience from the Center of the Neural Basis of Cognition (Carnegie Mellon/Pittsburgh). At IQ Mindware we develop brain training interventions to increase IQ, critical thinking, decision making, creativity and executive functioning.

1 Comment