You know that I have been research a lot of the latest findings in reasoning, intelligence, and working memory skills. A great article by one of my favorite casual authors in this area, Scott Barry Kaufman, recently published a short piece that I found really interesting.
He reviewed some research (so I am reviewing the review - a little derivative of me) that investigated the direct relationship of working memory on fluid reasoning. What I really liked about the findings is that the answer is "it depends." Anyone who follows me on social media or has taken any of my courses knows that I believe this is the answer to every good question.
In this case, the influence of working memory on fluid reasoning depends on the time allowed. When people are under time pressure, they fill up their working memory to do the reasoning quickly. So much of their fluid reasoning ability depends on their working memory capacity.
But when people have plenty of time, the relationship disappears. People don't need to fill up their working memory when they can just refer back to the original source while doing their fluid reasoning.
The implications are important. This means that if we are designing for contexts where there will be time pressure, we need to create good visual designs that integrate information together to reduce the amount of work the user has to do him/herself. Training on good visuospatial skills can also help.
Another recent study in Psychological Science found that mindfulness training can also help. Here, mindfulness improves your ability to resist distractions. By not filling up your working memory with irrelevant information, you have more left over for your reasoning task. In this study, mindfulness training increased working memory capacity (probably not really the capacity itself, but how much of it was available for the task) and thereby increased performance on GRE reading comprehension tests.