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Multitasking: Is It Working for You?
By Richard P. Mills, MD, MPH, Chief Medical Editor, EyeNet
(PDF 111 KB)

Some of you will remember EyeNet Audio, an Academy continuing medical education offering that I edited, which died a peaceful death at the age of three. The idea was that an ophthalmologist could listen to it while commuting in the car. The problem was, as I discovered while trying this myself, I kept missing the important messages when traffic demanded my attention. That was my first clue that multitasking was not for me. But, because multitasking was all the rage then, I kept quiet about my observation. Job applicants would list it as a skill on their résumé, young mothers would point proudly to it as a survival skill, some surgeons would talk on speakerphone to their brokers during operations and, of course, any computer worth buying could multitask. I worried that my brain might be wired wrong.

Thankfully, cell phones have made me realize that I am not alone in my disability. Much of the dumb driving I encounter is perpetrated by people with a cell phone on their ear, or who are gesticulating for no apparent reason. National Public Radio’s Car Talk, my favorite source for current science in psychology, tipped me off to two recent studies. One of them discovered that cell phone use is more deleterious to driving performance than conversations with a passenger, even when such conversations involve life-threatening experiences.1 Another study concludes that drivers on cell phones have the same driving impairment as those with a blood alcohol level of 0.08 percent.2 It turns out that hands-free cell phone use is just as dangerous because it’s not about the hands, it’s about the lack of concentration, and the delay in reaction time.

The peer-reviewed evidence against cell phone use while driving is fairly convincing, yet still there are skeptics. They point to methodological flaws in the studies and draw analogies to other driving distractions such as infants in the backseat, applying makeup while driving, reaching for the dropped sheet of directions—none of which can be outlawed. They also correctly point out that laws against hands-free cell phone use while driving are practically unenforceable. Police officers making a traffic stop would need to ask for your driver’s license and your cell phone to determine whether you were using it at the time of the alleged infraction.

Which brings me back to the matter of multitasking and the fact that cell phone use is merely the tip of the iceberg. It turns out that humans lose time when switching from one task to another, even more so when the tasks are complex.3 This is in contrast to computers, which can switch tasks in the blink of a binary bit. So multitasking may actually cause a decline in human efficiency. Philip Stanhope, Earl of Chesterfield, wrote to his son in 1747, “. . . steady and undissipated attention to one object is a sure mark of a superior genius; as hurry, bustle and agitation are the never-failing symptoms of a weak and frivolous mind.” I am willing to concede that as society becomes more frenetic, evolution may select for humans who can multitask better than the Earl of Chesterfield. Until then, I’m going to try to keep my focus and leave multitasking to my computer.

1 Drews, F. et al. J Exp Psychol Appl 2008;14:392–400.
2 Strayer, D. et al. Hum Factors 2006;48:381–391.
3 Rubenstein, J. et al. J Exp Psychol Hum Percept Perform 2001;27:763–797.