"Multitaskers cannot filter out irrelevant information because their attention is overloaded with whatever tasks they are not
"In one experiment, Professor Nass showed a pair of red triangles surrounded by two, four, or six blue rectangles for a brief moment to both high multitaskers and low multitaskers (people who don't normally try to do more than one thing at a time). Then he showed the same picture again, sometimes altering the position of the red triangles. The subjects were told to ignore the blue rectangles and to judge whether the red triangles had changed position. What he found was the low multitaskers had no problem with this task. However, the high multitaskers performed horribly. They could not ignore the blue rectangles and they could not tell if the red triangles had moved. What this means is that multitaskers cannot filter out irrelevant information because their attention is overloaded with whatever tasks they are not doing. In other words, a multitasker cannot actually distinguish between relevant and irrelevant information because the multitasker does not really know what they are doing at any given moment."
"Autopilot: The Art and Science of Doing Nothing" by Andrew Smart
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