Smarter summary

What’s the true measure of intelligence? IQ tests? Brain scans? Both are contenders.

Measuring fluid intelligence is challenging because there’s no way to directly observe it. That’s why psychologists call it a construct: a conceptual idea that we can’t directly observe but nevertheless can attempt to measure. Dark matter is another example of a construct: physicists use complex equations to measure it but they’ve never actually seen it.

Imagine if all you had to do to become smarter was play a quirky little game, like Angry Birds – an appealing prospect! It’s not entirely out of reach either. In fact that’s exactly what Lumosity offers.

Lumosity was co-founded by Michael Scanlon in 2007 during his neuroscience doctorate at Stanford. By April, 2013, it had already grown to a massive 40 million members. By turning psychologist-designed cognitive tasks into fun and engrossing computer games, Lumosity became a huge success.

Don’t feel like spending much more time at your computer? Never fear: There are ways to improve your intelligence that don’t involve staring at a computer screen.

As far back as the 1960s, research has suggested that physical fitness influences cognitive performance. In one study, elderly people who played tennis showed significantly better results on a variety of cognitive tests than those who didn’t exercise.

Why can’t scientists agree about whether or not you can improve your intelligence? And if evidence is so inconclusive, why’s the military so interested? A meta-analysis into research on brain training and intelligence has cast doubt on whether intelligence can really improve.

A meta-analysis uses various statistical techniques to make sense of differing results across studies. Patterns across studies allow for greater clarity among conflicting research.