Multitasking is starting to wear on me. There was a time when I prided myself on being able to do an enormous number of things at once; it can be a fun challenge to try to participate in a phone conference while chatting with someone on Google Talk, looking up rush hour train times, and deciding where to go for dinner. I’ve always had this nagging certainty, though, that as much as I like to think that my zealous multitasking is more efficient, it is actually making me slower by messing up my ability to concentrate—hardly far-fetched, when you sit down and consider it without a sandwich in one hand and a cell phone on the opposite shoulder.

Well, it turns out that science is catching up with my nagging doubts. Apparently the human brain has a faculty that’s usually called “executive control,” which handles the rapid switching of focus between the phone conference, the Google Talk conversation, the train schedule, and the dining possibilities. Studies like this one seem to consistently show that the constant back-and-forth switching slows us down.

A somewhat notorious study at the Institute of Psychiatry at the University of London even pitted workers distracted by frequent emails and phone calls with workers who were experiencing the effects of recent drug use, and found that the email junkies fared WORSE than the drug users.

All in all, it might not be so bad to do one thing at a time for a little while.