Why People’s Cell Phone Conversations Annoy Us
Listening to Other People’s One-Sided Conversations Leads Our Brains to Try to Figure Out What the Other Person Might Be Saying
Sept. 22, 2010 -- Overhearing a cell phone conversation is not only annoying but distracting because it leads the brain into trying to decipher what the person on the other end of the call is saying, making concentration more difficult, a new study shows.
Cornell University doctoral student Lauren Emberson, BSc, and colleagues enlisted 41 volunteers to test whether their thinking abilities were most affected by listening to two people talking in conversation, a monologue, silence, or only one side of a conversation, called a “halfalogue.”
The results were clear -- the participants listening to only one side of a conversation had lower scores on a series of cognitive tests that required attention and focus.
Emberson tells WebMD in an email that listening to only one side of a conversation drains concentration, because the brain must work harder to figure out what the other person might be saying.
Prediction a Key to Understanding
People who hear only one side of a conversation get less information and thus can’t predict what’s being said, Emberson tells WebMD.
When listening to a monologue or to a two-sided conversation, it’s easier to predict what speakers will say next. But the human brain can’t make predictions, she says, when it hears only one side, which also may explain why people become annoyed when they overhear others on cell phones.
Emberson tells WebMD the study shows that “hearing both halves is not distracting, but hearing one half of a conversation is. Our paper also includes a control [comparison] study showing that when the information content of the speech is unintelligible, the half of a conversation doesn’t affect your attention.”
The same is likely true when people are trying to read or watch TV at the same time someone is talking nearby on a cell phone or even a landline, she says.
Predicting Is a Reflex
“Attention is reflexively shifted to their conversation because of the unpredictability of the speech,” Emberson tells WebMD.
She enlisted two pairs of college roommates as they talked on a cell phone, then recorded each conversation both as a dialogue, in which both women could be heard by a listener, and as a halfalogue, in which only one side of the conversation could be discerned. Then each woman recapped the conversation in a monologue. The recordings were played back as volunteers performed various tasks on a computer, such as tracking a moving dot using a mouse.