Have you ever seen a friend yawning and instantly felt the need to yawn -- even if you weren't feeling sleepy?
New research shows that the act of pulling out a cell phone is also a "contagious" behavior and may jolt someone nearby to pull out his or her mobile device, too.
In 2011, two researchers at the University of Michigan conducted a study in which they observed pairs of young people roughly between 16 and 25 sitting at tables in dining halls and restaurants in and around campus. They recorded cell phone use in 10-second intervals, noting if one or both people checked a mobile device within each 10-second span, according to the paper published in the Human Ethology Bulletin.
On average, individuals used cell phones during 24 percent of the intervals, validating previous research that checking out portable gadgets is an "addictive" behavior. University of Michigan researchers also found that if "Person A" peeked at his or her phone or made a call during a 10-second interval, "Person B" reached for his or her cell phone 39.5 percent of the time in the following interval.
The University of Michigan's Julia A. Finkel and Daniel J. Kruger, who caveat their findings by pointing out that results may differ with older adults, pinpoint two potential causes for the contagiousness of cell phone use.
The first is prompting: An individual remembers to check her email, for example, only when the friend she's with checks his.
The other is inclusion: When one person pounds out a text or chats with a friend on a phone, the other person, excluded from that digital conversation, is more likely to seek out some social interaction herself by, say, checking Facebook. It seems no one wants to feel like an outcast, even for a moment.
Earlier on HuffPost:
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