16:55 01 March 2016
Scientists at the University College London has found that focusing on something visual renders people temporarily deaf.
The study was participated by 13 volunteers who were asked to complete increasingly difficult tasks and had to listen out for sounds.
Dr Maria Chait explained: "The brain scans showed that people were not only ignoring or filtering out the sounds, they were not actually hearing them in the first place."
Professor Nilli Lavie added: "Pedestrians engaging with their phone, for example texting while walking, are also prone to inattentional deafness.
"Loud sounds such as sirens and horns will be loud enough to get through, but quieter sounds like bicycle bells or car engines are likely to go unheard."