WHAT!?

Hey guys Julia here for DNews

Have you guys ever been on a train playing on your phone and suddenly you’ve missed

your train stop? Or if you’re like me, your family thinks you’ve suddenly gone deaf

when you’ve got your nose stuck in a book. This has become an actual recurring problem

in my life. But aha! Science vindicates me! Apparently focusing on something visual does

makes us kind of deaf. It happens to most of us.

It’s called “inattentional deafness” according to a study published in the journal

Attention, Perception, & Psychophysics. The researchers tested over 100 participants and

had them focus on tasks on a computer screen and they played a noticeable tone. When the

task demanded more attention, eight out of ten participants failed to notice the tone.

And this isn’t exactly news. Humans aren’t that good at paying attention to lots of different

things at the same time. We can focus, we just can’t pay attention. Researchers have

known for years about “inattentional blindness”, which like it sounds is when you don’t see

something happening because you were focused on something else. The classic example is

the “invisible gorilla test”. Where you watch people pass a basket ball back and forth

and count how many times they passed it. But in the middle of the video a person in a gorilla

suit walks in, beats their chest, and walks out. In one study of this video, 42% of people

didn’t notice the gorilla. At all because they were so focused on the basketball.

So what’s going on? Well a recent study published in the Journal of Neuroscience found

our brains aren’t as efficient as we’d like to think. In this small study, researchers

hooked up 13 volunteers to a brain activity measuring device called a MEG. This machine

is used to measure how long it takes for an “unusual sensory signal” to get from your

brain to your consciousness. Basically, how long it takes for you to recognize something

after you see or hear it. This typically takes 300msec, and is referred to as a p3 reading

.

In the study the volunteers were given a visually demanding task, like matching things on a

computer. While they were engrossed in their task, the researchers played a tone. The scientists

found that the volunteers were so focused on matching things, their P3 response was

suppressed. Which means they didn’t consciously perceive the sound. And another reading suggested

that they didn’t even hear it.

The MEG also looked at activity in the superior temporal sulcus and posterior middle temporal

gyrus, which are parts of our brain that usually light up in response to hearing a sound. But

since the volunteers were so focused on the task, even this reading was weak. So really,

when you’re focusing really hard on something, your brain barely hears it and it doesn’t

even reach your consciousness.

The researchers found that this is because the senses of hearing and vision share a limited

neural resource. Simply put, your brain doesn’t have the resources to consciously perceive

multiple things at the same time.

So take that mom and dad! I wasn’t ignoring you when I was reading, I literally couldn’t

hear you!