ScienceBlog reports on how media multitasking is really multi-distracting.

Placed in a room containing a television and a computer and given a half hour to use either device, people on average switched their eyes back and forth between TV and computer a staggering 120 times in 27.5 minutes — or nearly once every 14 seconds, Carroll School of Management professors S. Adam Brasel and James Gips report in a forthcoming edition of the journal Cyberpsychology, Behavior, and Social Networking.

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What’s more, the subjects were not even aware of their own actions. On average, participants in the study thought they might have looked back and forth between the two devices about 15 times per half hour. In reality, they were looking nearly 10 times as often. And even if quick “glances” less than 1.5 seconds are removed from the equation, people were still switching over 70 times per half hour.

If simply being in an urban city can impair your memory and "dull your thinking", just imagine how much multitasking interferes with learning.