Multi-tasking (or “dual-task performance,” since your brain almost always switches back and forth among tasks) has always been a part of life. Just getting the family out of the house and on its way in the morning is an exercise in ordered chaos, and we usually do it pretty well. But it comes at a cost: We pack a lunch but then forget to take it, and everything seems to take a little longer.Don’t believe me? Here’s an experiment Hopkins professor and clinician Martha Denckla did with us at a conference over the weekend. Do this out loud (or mumble if you’re going to distract someone):
1. As fast as you can, say out loud the numbers 1 through 10.
2. As fast as you can, say the letters of the alphabet A to J.
3. Now, as fast as you can, alternate the numbers and letters: 1-A, 2-B, etc.
If we were true multitaskers, Case 3 would take us exactly the same time as Case 1 plus Case 2. For most of us in the audience, it took far longer. Why?