In 2005, a psychiatrist at King’s College London did a study in which one group was asked to take an IQ test while doing nothing, and a second group to take an IQ test while distracted by e-mails and ringing telephones. The uninterrupted group did better by an average of ten points, which wasn’t much of a surprise. What was a surprise is that the e-mailers also did worse, by an average of six points, than a group in a similar study that had been tested while stoned.
That’s right. Stoned. Those people were literally burned out, and they did better.
via nymag.com