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Scientist 'prove theory of selective deafness'

20 June 2012 Last updated at 10:19 BST

New research suggests people filter out sound automatically and can become deaf to other noise.

Scientists asked volunteers to listen to a conversation between two men and two women, concentrating on what the women said.

Dr Polly Dalton, one of the people behind the study, and psychologist Emma Kenny explained how it worked.