A study has found that becoming engrossed in a good book or a crossword really can block the ability to hear.
Scientists demonstrated that when someone focuses their full attention on something, they could become deaf to normally audible sounds.
It happens because visual and hearing senses are trying to share limited brain capacity, they said.
For example, when engrossed in a good book or even a captivating newspaper article, we may fail to hear the train driver's announcement and miss our stop.
''Or if we're texting while walking, we may fail to hear a car approaching and attempt to cross the road without looking," added Lavie.
Lavie said: "Hearing is often thought to have evolved as an early warning system that does not depend on attention, yet our work shows that if our attention is taken elsewhere, we can be effectively deaf to the world around us."
The study has been published in the journal Attention, Perception And Psychophysics.