Many of us will admit to the notion that eavesdropping is engrossing, but at the same time we don’t realise the extent of attention it commands. Researchers from Royal Holloway (University of London) say that people concentrating on a conversation are ‘deaf’ to other sounds in the surrounding.
Researchers created an auditory scene with one conversation between two men and another between two women. During the observation, they introduced a man to shout ‘I'm a Gorilla’. The sequence of the chant was repeated for 19 seconds. It was observed that participants listening to the chatting women were so engrossed in the conversation that they didn’t notice the shouts of the man. Over two-thirds of the total participants eavesdropping on the conversation between the women could not notice the man shout ‘I'm a gorilla’.
The 'invisible gorilla' experiment of 1999 was similar in nature in which people failed to spot a person in a gorilla suit walking through a basketball field. This was an illustration of how an intense conversation can leave us deaf. The effect has since the study been named 'silent gorilla' effect in hearing.
The detailed report of the research is published in the journal Cognition.