Another big neuroscience theory hits the baff wall
|October 2, 2013||Posted by News under Neuroscience, News|
Mr. Gladwell enjoys a reputation for translating social science into actionable insights. But the data behind the surprising dyslexia claim is awfully slim. He notes in passing that a 2009 survey found a much higher incidence of dyslexia in entrepreneurs than in corporate managers. But this study involved only 102 self-reported dyslexic entrepreneurs, most of whom probably had careers nothing like those of Mr. Boies or his fellow highfliers. Later Mr. Gladwell mentions that dyslexics are also overrepresented in prisons—a point that would appear to vitiate his argument. He addresses the contradiction by suggesting that while no person should want to be dyslexic, “we as a society need people” with serious disadvantages to exist, for we all benefit from the over-achievement that supposedly results. But even if dyslexia could be shown to cause entrepreneurship, the economic analysis that would justify a claim of its social worth is daunting, and Mr. Gladwell doesn’t attempt it.
To make his point about the general benefits of difficulty, Mr. Gladwell refers to a 2007 experiment in which people were given three mathematical reasoning problems to solve. One group was randomly assigned to read the problems in a clear typeface like the one you are reading now; the other had to read them in a more difficult light-gray italic print. The latter group scored 29% higher, suggesting that making things harder improves cognitive performance. It’s an impressive result on the surface, but less so if you dig a bit deeper.
First, the study involved just 40 people, or 20 per typeface—a fact Mr. Gladwell fails to mention. That’s a very small sample on which to hang a big argument. Second, they were all Princeton University students, an elite group of problem-solvers. Such matters wouldn’t matter if the experiment had been repeated with larger samples that are more representative of the general public and had yielded the same results. But Mr. Gladwell doesn’t tell readers that when other researchers tried just that, testing nearly 300 people at a Canadian public university, they could not replicate the original effect. Perhaps he didn’t know about this, but anyone who has followed recent developments in social science should know that small studies with startling effects must be viewed skeptically until their results are verified on a broader scale. They might hold up, but there is a good chance they will turn out to be spurious.
If you can’t replicate something at a Canadian public university, you should know you are in trouble already.
Intelligence is, honestly, the original It Came From Beyond Space.
Hat tip: Stephanie West Allen at Brains on Purpose