Register for an account


Enter your name and email address below.

Your email address is used to log in and will not be shared or sold. Read our privacy policy.


Website access code

Enter your access code into the form field below.

If you are a Zinio, Nook, Kindle, Apple, or Google Play subscriber, you can enter your website access code to gain subscriber access. Your website access code is located in the upper right corner of the Table of Contents page of your digital edition.


Does E-mail Make You Dumber?

By Anne CasselmanAugust 6, 2005 5:00 AM


Sign up for our email newsletter for the latest science news

If you feel like a zombie at work, perhaps you’re suffering from infomania, the term the Hewlett-Packard affiliate in Britain coined for people addicted to e-mail, instant messaging, and text messages.

A recent study for the company found that British workers’ IQ test scores drop temporarily by an average of 10 points when juggling phones, e-mails, and other electronic messages—more of an IQ drop than occurs after smoking marijuana or losing a night’s sleep. “This is a very real and widespread phenomenon,” said Glenn Wilson of the Institute of Psychiatry at the University of London, who conducted the tests on some 1,100 volunteers. Just how long it takes to recover is unclear.

The study found that modern-day communications have become addictive: Sixty-two percent of adults check work messages after office hours and on vacation. Half of those surveyed reply to an e-mail immediately or within 60 minutes. About 20 percent were “happy” to interrupt a business or social meeting to respond to a telephone or e-mail message. Yet 89 percent of those surveyed found it rude for colleagues to do so.

Whether infomaniacs are less intelligent is another question. “It didn’t affect their IQ at all; it affected their performance on an IQ test,” says Bob Stickgold, a cognitive neuroscientist at Harvard University. “When you’re taking an IQ test, you probably want to be really focused. That’s the antithesis of the state you get into when you do a lot of multitasking.”

The human brain has evolved different modes for concentrating on a single thing versus jumping from one thing to another. “The reason we have these systems that quickly shift between each other is because what’s right for you now might not be right later,” Stickgold says. “There are basic brain-stem mechanisms that will cause you to shift and focus your attention on a change in stimulus.”

Whether that change is a saber-toothed tiger popping out of the woods or a phone ringing suddenly, the consequences are the same. “The switch signal comes fast and powerfully. This system knows at a moment like this that what’s important is to shift your state quickly, and damn the cost. And the cost is that it takes several minutes to shift back,” says Stickgold. “That’s the way we’re wired.”

3 Free Articles Left

Want it all? Get unlimited access when you subscribe.


Already a subscriber? Register or Log In

Want unlimited access?

Subscribe today and save 70%


Already a subscriber? Register or Log In