A new study by British researchers revealed that focusing on a visual task will make people deaf to sounds coming from their surroundings.
The study, published in the Journal of Neuroscience, showed that concentrating attention on a visual task can render you momentarily ‘deaf’ to sounds at normal levels. If you don’t receive a response from someone who’s focusing on a book, game or TV, they aren’t necessarily ignoring you, but might simply not hear you.
The researchers say that the senses of hearing and vision share a limited neural resource. The study involved 13 people whose brain were scanned and the researchers found that when people were engaged in a demanding visual task, the brain’s response to sound dropped significantly. In addition, they noticed that people were unable to detect sounds during the visual demanding task, even though the sounds were clearly audible and people did detect them when the visual task was easy.
This phenomenon is called ‘inattentional deafness’, which has been observed by the researchers before. But, for the first time, the researchers was able to determine that the effects are driven by brain mechanisms at a very early stage of auditory processing, which would be expected to lead to the experience of being ‘deaf’ to these sounds.
“Inattentional deafness is a common experience in everyday life, and now we know why,” says Professor Nilli Lavie, who is study’s co-author. “This could also explain why you might not hear your train or bus stop being announced if you’re concentrating on your phone, book or newspaper.”
“This has more serious implications in situations such as the operating theatre, where a surgeon concentrating on their work might not hear the equipment beeping. It also applies to drivers concentrating on complex satnav directions as well as cyclists and motorists who are focusing intently on something such as an advert or even simply an interesting-looking passer-by.”