I want to listen to two songs at the same time, brain: No, I can't do that

I wonder if you have ever had this experience:

If several people are talking at the same time and saying different things, we cannot pay attention to what everyone is saying. When we choose to listen carefully to one of them, all other voices seem to "disappear".

The same is true when listening to music. It is difficult for us to focus on two different pieces of music.

Logically speaking, all sounds from the outside world that enter the ear can stimulate the eardrum and transmit sound signals to the brain. So, is the inability to listen to two songs at the same time the result of the brain selectively ignoring certain sounds?

Single-threaded brain

Research has found that humans generally have limited abilities when it comes to handling two or more tasks simultaneously.

Under normal circumstances, the human brain is in a single-threaded state. During the transmission of auditory information, some nerve cells, including the primary auditory cortex, show strong selectivity for the direction of change in sound frequency, so it is easier for us to focus on one sound.

As for why it is single-threaded, there is currently a speculation: in primitive society, humans have to focus more on hunting and escaping, so their attention can only be focused on one thing, so as to obtain a greater chance of survival.

Many people are curious: since the brain runs on a single thread, why can some people do two things at once? What secrets are hidden in this?

Image source: pexels

The cut brain runs

Listening to music and reading a novel at the same time, both things require concentration, but some people can do two things perfectly. But in fact, what you think is "perfect" is just an illusion.

The prefrontal cortex plays a key role in the brain's processing of information. It helps the brain separate things and perform them alternately. Because the alternation process is very fast, it makes us mistakenly think that two things are happening at the same time.

Neuroscience research has proven that the brain's prefrontal cortex tends to handle only one task at a time. If the brain needs to handle two different things at the same time within 300 milliseconds, the processing speed of the second thing will be slower.

People can improve their efficiency through practice, but it is impossible to eliminate the transition time between two things. Therefore, strictly speaking, we cannot really achieve "multitasking".

Image source: pixabay

If you think a person can do two things well, it means that the other person must have put more energy into one thing. When the other person can handle two or more things at the same time, not only can't improve efficiency, but it will get half the result with twice the effort.

When we exit from one task and switch to another, the brain needs some time to clear the cache and write new task information. The accumulation of this period of time is a considerable amount of time. When we switch tasks, if the previous task is not completed, then this task will leave part of the memory in our mind. This part of the memory is called "attention residue", which will not only occupy our cognitive resources, but also reduce our energy to handle another task.

When we experience switching multiple times, a large amount of useless "attention residue" will accumulate in our minds, and the energy and resources we have will become very limited.

An experiment in 2019 found that when we listen to music while working, our creativity, memory and comprehension abilities all decline to varying degrees. Even if we like the music and it brings us emotional happiness, it is a burden to the brain.

Screenshot of the paper

While it is generally difficult for us to multitask, there are exceptions.

Simple repetition consumes too little attention

When you are doing two tasks at the same time, one of which does not require any attention to complete the task, in this simple mechanical environment, it is possible to do multiple tasks at the same time. When we are walking, we can listen to music or talk to others very well.

This is because the task of "walking" is an extremely simple task for the cerebellum, which can fully handle it without occupying the resources of the brain.

Image source: pexels

It turns out that "multitasking" is not as perfect as we imagined. The rapid switching of attention will also cause a certain amount of pressure on the brain. Since we can't achieve "doing two things at the same time", we might as well focus on the present, prioritize things, and solve them one by one.

Focusing on the present may be a better way to solve the problem.

END

Reviewer: Yin Tielun, deputy chief physician of the Department of Neurology, Peking University Third Hospital Airport Branch

Editor/Heart and Paper