To better understand executive control, as well as the human capacity for multitasking and its limitations, Rubinstein, Meyer and Evans studied patterns in the amounts of time lost when people switched repeatedly between two tasks of varying complexity and familiarity. In four experiments, young adult subjects (in turn, 12, 36, 36 and 24 in number) switched between different tasks, such as solving math problems or classifying geometric objects. The researchers measured subjects' speed of performance as a function of whether the successive tasks were familiar or unfamiliar, and whether the rules for performing them were simple or complex.Unless you're mopping the floor or emptying the trash, that Blackberry might improve your efficiency if you just turned it off during meetings.
The measurements revealed that for all types of tasks, subjects lost time when they had to switch from one task to another, and time costs increased with the complexity of the tasks, so it took significantly longer to switch between more complex tasks.
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