In an experiment, people who had been using smartphone-sized iPod Touch devices were 47% less likely than desktop users to get up to try to find out why a researcher hadn’t come back after leaving the room to fetch paperwork so that participants could be paid. And of those who did take action, the iPod Touch users took 44% longer than desktop users to get up and look for the researcher. The research suggests that your hunched posture as you use a smartphone-sized device for just a few minutes makes you less likely to engage in power-related behaviors than people who have been using desktop computers, say research fellow Maarten Bos and Amy Cuddy of Harvard Business School.
Source: http://hbswk.hbs.edu/item/7271.html
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