What part of the brain controls blinking?

In the following article we will answer the question’’What part of the brain controls blinking?’’, we will talk about what blinking is for, how the brain reacts to it and this apparently involuntary action has another hidden meaning.

What part of the brain controls blinking?

The part of the brain that controls blinking is the orbitofrontal cortex, the process of blinking, specifically intensity, is regulated here. The orbitofrontal cortex is the area related to cognitive processing of decision making that is located in the frontal lobe of the brain.

We call blinking the process by which we open and close the eyelids at a relatively high speed. This action is semi-voluntary, so it is possible to restrict or provoke it voluntarily if we so desire and pay attention or even temporarily cancel it, but as a general rule its performance escapes our consciousness.

The human being blinks on average around fifteen to twenty times per minute, although he does not do so following a fixed time pattern but it depends on the circumstances.

What are the causes of blinking?

Blinking is produced mainly by the action of the striatum, part of the basal ganglia (located deep in the brain), and is especially linked to the structure called the globe pallidus. Involvement on the part of the cerebellum has also been found.

Likewise, the autonomic nervous system is also linked to the blink reflex, inhibiting or facilitating it due to the need to activate the body and pay attention to the environment or relax it.

Why do we blink?

The main reason why we blink is to keep the eye protected and lubricated: since the eyes are the organ linked to the most external perception that we have (along with the skin), it is necessary to be able to defend it from harmful chemicals that can be harmful. 

It also requires lubrication to function constantly and allow a clear and clean vision, which allows flickering.

In addition, the eyes are in constant operation and receive information continuously, so that it is necessary to be able to make them rest.

What does blinking work for?

Blinking is an action that has multiple uses and can be altered for different reasons. Some of the main functions of blinking are as follows.

Eye defense

The blinking allows us that the eye is not damaged by external harmful agents, such as chemical substances, physical aggressions (we tend to blink when we see something get too close to our eye) or even by an excessive level of light that can damage the interior of our eye.

Lubricate and clean the eye

The surface of the eye is a lens in which the images from the outside will be reflected. One of the functions of the fact that we blink is to keep the cornea clean and allow its proper functioning and state of health, since by blinking we spread tears over the entire surface of the eye.

Relax the eye and brain

In addition to the eye, blinking is a relief on specific parts of the brain. The brain has been shown to decrease the activation of the visual nuclei during the moments when we blink, which helps us organize visual information.

What can affect the blink rate?

There are multiple circumstances that can alter the blink rate in humans. They generally have to do with the mood or level of arousal or arousal. Some of the aspects that alter the blink rate or frequency are the following

1. Attention, surprise and interest

When something surprises us or catches our attention, we tend to greatly decrease the frequency with which we blink and even stop for a few moments. This allows us not to lose information about the new situation or what captures our interest.

2. Boredom and disinterest

When they are tired and / or bored, most individuals appear to blink less and more slowly.

3. Anxiety and nervousness

When we are nervous, stressed, or anxious, most people tend to blink continuously and much more frequently than usual.

4. Consumption of psychoactive substances

Consumption of different substances with psychoactive effects can also alter blinking, reducing or increasing it.

5. Medical illness or mental or neurological disorders

Different medical illnesses or even mental disorders have been shown to cause either alteration or elimination of blinking. In fact, the absence of blinking can be understood as a symptom of a disorder.

People who suffer from tic disorders, cerebrovascular accidents or dementias or other disorders that present with a progressive degeneration of mental functions usually have altered or even absent blinking.

Alterations have also been seen in subjects with mood disorders (people with depression tend to blink less and more slowly while people in manic phases tend to blink more). Similarly, people with schizophrenia and other psychotic disorders can present these types of alterations.

What does the brain do to avoid darkness by blinking?

Parts of the brain that control vision turn off every time we blink to avoid the feeling of darkness.

The tests revealed that during blinking, brain activity in the visual cortex and other areas of the brain that are normally activated by perceiving visual elements is suppressed.

This would explain why we do not suffer a blackout every time we blink.

What’s the use of blinking?

The human eye needs to blink to distribute the tear produced in the lacrimal glands over its surface. This tear is made up of 3 layers; lipid, watery and mucinous (allows the tear to adhere to the ocular surface). It has numerous functions (entertainment, antiseptic, optical and nutrition), the lubricating function being the best known.

The blink frequency varies greatly between individuals and even in the same individual depending on the situation in which they are. For example, when we fix our vision on something for a long time, like when we use a computer, we decrease the frequency of blinking, thus increasing the evaporation of tears.

However, this is much more than is necessary to keep the eye lubricated, which is why the idea is raised that eye blinking may have another biological meaning, apart from those already known, since that excess blinking would not make sense considering account that it blocks our field of vision for longer than required to maintain eye health.

Given this idea, scientists from the University of Osaka (Japan) have developed a hypothesis; when we blink, the brain rests. 

To understand this, we must know that at the brain level we distinguish two fundamental neural networks; the default neural network  and the back care neural network, made up of interrelated subsystems that show a functional correlation.

Does the brain rest when we blink?

Scientists from the University of Osaka (Japan) have developed a hypothesis; when we blink, the brain rests. 

To understand this, we must know that at the brain level we distinguish two fundamental neural networks; the default neural network and the back care neural network, composed of interrelated subsystems that show functional correlation.

The neural network by default is activated in a state of rest, freeing us from the attention of external stimuli and allowing us to focus on mental processes or cognitive tasks, that is, it allows us introspection.

 On the contrary, the dorsal attention neural network is activated in the moments in which we are developing a task, which allows us to focus our attention on what surrounds us.

On the other hand, we have to be attentive to the moments in which spontaneous blinking occurs, because if we pay attention, it always happens following certain guidelines.

As a general rule, we blink after moments of great attention, as if this helps us to process what is happening; for example at the end of sentences while reading, or in the pauses that an interlocutor makes during a conversation, or in the moments of cessation of activity in a movie …

Putting these data together, various studies have been carried out in which it has been found that in those moments in which a spontaneous blinking occurs (preceded by moments that have required some attention to external stimuli), the activity in the network decreases. Back attention neural network and increases activity in the predetermined neural network.

This has been studied through the use of functional magnetic resonance images that show us the metabolism and blood flow, and therefore the activity, of each area of ​​the brain at certain times.

From this it is concluded that blinking is involved in actively releasing attention from our surroundings, in order to focus on internal mental processes.

Visual system ‘flashes’?

The impulses in the primary visual cortex present a brief interruption when we switch our attention from one stimulus to another, as found in macaques.

When we shift our attention from one place to another, our brain makes a kind of “blink.” The metaphor is valid to refer to the momentary and unconscious interruptions that occur in visual perception when we change our focus of attention.

As researchers at Vanderbilt University have discovered in macaques, impulses in the primary visual cortex are interrupted for a short time when we shift our attention from one place or object to another.

The results

The researchers trained the macaques to play a video game in which they had to pay attention to certain visual objects. If they did it correctly, they received apple juice as a reward. 

Once the primates became adept at the task, the experimenters recorded the activity of their visual cortex.

The authors found that the activity of neurons in the primate visual cortex was momentarily interrupted when the game required them to change their focus of attention. After this brief suppression of impulses, the now attended stimuli elicited more activity in neurons than the neglected ones.

This phenomenon is related to the attentional blinking described in 2005 by David Zald and René Marois, also from Vanderbilt University.

This phenomenon occurs when images are presented to us successively and rapidly; if the space between two photographs is too short, we do not detect the second. Zald determined that the time of “temporary blindness” after violent or erotic images is longer than that associated with emotionally neutral snapshots.

Why do we blink automatically?

This automatic and involuntary action is part of an ancient protection mechanism. In our daily life we constantly look. We see and analyze what we observe through our eyes and, in fact, a large part of our cerebral cortex is dedicated to processing visual data.

However, every few seconds something happens that many times we do not even realize: we close our eyes to open them again immediately.

In other words, we blink. This action can be forced and even controlled by us if we pay attention to it, but as a rule it is something that we do unconsciously and involuntarily.

FAQS: What part of the brain controls blinking?

What’s the brain part that makes you blink?

Although one might assume that the stimulus causing blinking is dry or irritated eyes, a body of nerve cells between the base and outer surface of the brain is most likely regulated by a “blinking center” of the globus pallidus of the lenticular nucleus.

What’s the brain part that makes you blink?

Although one might assume that the stimulus causing blinking is dry or irritated eyes, a body of nerve cells between the base and outer surface of the brain is most likely regulated by a “blinking center” of the globus pallidus of the lenticular nucleus.

Is blinking voluntary or involuntary?

You can blink your eyes willingly, but it’s sometimes automatic to blink your eyes. Moving bones is the main feature of the muscular system. Help and protection for the organs is also offered by the muscular system.

Can we control blinking of our eye?

You can’t manage it. This is called blinking or twitching involuntarily. A muscle spasm around your eye is responsible for the twitching.

What does blink rate indicate?

A reliable measure of cognitive processing can be given by the blink rate (BR: the number of blinks per minute) during choice-response tasks. The intervals of consecutive blinks between peaks were stacked into a sequence, referred to as BRV.

In the following article we answerWS the question’’What part of the brain controls blinking?’’, we talkED about what blinking is for, how the brain reacts to it and this apparently involuntary action has another hidden meaning.

If you have any questions or comments please let us know!

References

“Spiking suppression precedes cued atttentional enhancement of neural responses in primary visual cortex”. Alexander Maier et al. in Cerebral Cortex, published online, 2017.

“Functional MRI of Brain Activation by Eye Blinking”   Kasuo, T., Kenneth, K., Tsung, L., Jiro, N. & Hong, C.  Japan. 2002. https://www.sciencedirect.com/science/article/abs/pii/S0014483599906607#!

“Eye-blinking artefacts analysis”  Manoilov, P . CompSysTech ’07: Proceedings of the 2007 international conference on Computer systems and technologies June 2007 Article No.: 52 Pages 1–6 https://doi.org/10.1145/1330598.1330654