Sometimes the switch from one task to another costs us only a few tenths of a second, but in a day of flip-flopping between ideas, conversations, and transactions on a phone or computer, our switch costs can really add up, and make us more error-prone, too.
Every time we switch tasks, we’re also shooting ourselves up with a dose of the stress hormone cortisol.
http://www.businessinsider.com/what-your-smartphone-is-doing-to-your-brain-and-it-isnt-good-2018-3
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