Eavesdropping so engrossing that it can make you deaf

Many may not admit it, but eavesdropping is so engrossing that majority of the people listening to girlish gossip fail to notice even if a man says something very unusual like "I am a gorilla", a new study says.

Researchers from Royal Holloway, University of London, found that more than two thirds of those eavesdropping on the women failed to notice a man chanting "I am a gorilla" repeatedly for 19 seconds over the conversation.

The study, published in the journal Cognition, was an example of how intense conversation can leave us 'deaf' to the world around us, the researchers said.

A famous study from 1999, in which people watching a basketball game failed to spot a man walk through in a gorilla suit and beat his chest, revealed how focusing on one thing can leave us "blind" to events happening right in front of us.

But this study is the first to show that hearing is similarly affected, the Daily Mail reported.

The researchers placed two men at a table in a room and two women at another table and recorded them talking about getting ready for a party.

Some of their conversation overlapped.

Halfway into the recording, a man walked through the room, repeating the phrase "I am a gorilla".

The recording was then played to a group of volunteers.

Some listened to the women’s conversation and others to the men’s, believing they would be asked afterwards about what had been said.

In fact, they were asked if they had heard anything unusual -- and only 30 per cent of those listening to the women spotted the interloper, the researchers said.

Lead researcher, psychologist Dr Polly Dalton, said: "This research demonstrates that we can miss even very surprising and distinctive sounds when we are paying attention to something else.

"We were surprised to find such extreme effects with a listening task because people often think of hearing as an 'early warning system' that can alert us to unexpected events that occur out of sight.

"This has real-world implications in suggesting, for example, that talking on your mobile phone is likely to reduce your awareness of traffic noises."

Interestingly, the researchers found that almost of all those listening to the men’s conversation heard the "gorilla" man.

They said they could have been more "tuned in" to a male voice.

He had also been slightly closer to the men’s table.