Why You Go Deaf When You're Reading

Some people can't focus on more than one thing at a time. Why is it so hard?

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For those of you avid readers out there, you likely know this sensation quite well. You become drawn into the book and act of reading itself so much so that you're able to tune out external sensations. If you're at a café reading, you're not bothered by all the noise and bustle of activity.

Scientists refer to this as "inattentional deafness." A study published in the journal Attention, Perception, and Psychophysics gathered 100 participants who all focused on computer-related tasks. During their work time, the researchers played a noticeable audible tone, but during the attention-heavy tasks, as many as 80 percent of participants failed to notice the tone at all. These findings echo what scientists have long known about "inattentional blindness." There's a famous study involving a video a group of basketball players. Research participants were asked to count how many times the players passed the ball. During the video, a man in a gorilla suit walks through the frame, but 42 percent of participants did not notice the gorilla at all.

What's the reason for this? A new study in the Journal of Neuroscience posited that, when our brain is immersed in an intense task, the time it takes the brain to convey information to our consciousness is delayed. This process is known as the P3 Response. The team found that our auditory and visual senses share a limited neural resource. This partially explains how we tend to "zone out" from time to time.

Read More:
Why focusing on a visual task will make us deaf to our surroundings (Medical Xpress) "Examination of people's ability to detect sounds during the visual demanding task also showed a higher rate of failures to detect sounds, even though the sounds were clearly audible and people did detect them when the visual task was easy."

Visual perceptual load induces inattentional deafness (NIH)
"A wealth of research has suggested that the extent to which focused attention on a task results in reduced perception of irrelevant information depends on the level of perceptual load in the task."