I was walking in front of Grand Central Terminal on 42nd St. one evening and overheard a man in a business suit talking — and lying — on his cell phone. “I’m in the supermarket,” he said. “Just got here.”
I turned in amazement as the man passed, and spent the rest of the evening speculating about the possible scenarios. Was the person on the other end of the line his wife? His girlfriend? Was he a scoundrel on his way to a romantic assignation or a dreamboat who had just picked up a surprise birthday gift and was coming home with it? I had been snagged — like so many people are — by the power of the “halfalogue.” (More on Time.com: 6 Common Sources of Radiation In Your Life)
Public cell-phone conversations are maddening for a lot of reasons — their ubiquity, their volume (the conversational equivalent of a leaf blower), their banality (“I prefer the asparagus tips, but these were overcooked…”). But a new study published in the journal Psychological Science suggests that there might be something subtler at play: presented with half a conversation, our brains feel compelled to fill in the blanks.
Laura Emberson, a PhD candidate in psychology at Cornell University, came up with the idea to investigate the halfalogue when she was an undergraduate student commuting by bus and realized that she found it impossible to concentrate if someone was talking on a cell phone anywhere within earshot. In her recently completed study, she recorded a cell phone conversation between two people — first with both halves of the conversation audible, then again with only one half or the other recorded. Then she played either the full dialogue or the halfalogue to subjects while they tried to perform an onscreen task such as tracking a dot with a cursor.
The result was what she predicted: judging by their performances on the screen test, the people who heard the entire conversation were better able to proceed with the task than those who heard only half of it. (More on Time.com: Want Good Health? There Are 10 Apps for That)
The reason, Emberson thinks, has to do with the phenomenon of predictability. Human beings are vigilant animals and our brains don’t like to be uncertain about what’s going on around us. There are no secrets in an entire conversation, and once we take its measure, we can put it away. A halfalogue is a different matter. If you overhear someone say “What did the doctor tell you?” or “Don’t shout at me!” you can’t help but wonder what’s going on at the other end of the line. Even a less loaded halfalogue (“I’m going to be 20 minutes late”) may raise an unconscious question (“Why?”).
Emberson says her work has made her more sensitive to her own public halfalogues — and we all should be. It’s not only strangers’ ears that deserve a break from cell-phone chatter, it’s their brains too.
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