Insula

Insula is also known as insular cortex. This amazing structure is situated in the folds of cortex which is the topmost layer of cerebrum.

People call insula with different names. It is insular cortex, insularly lobe or even insula cortex.  

This tiny structure has been enigmatic since the beginning of time. Back then there were no brain imaging Technologies and because of this reason, insula remained hidden in the depths of cortex for a long time.

Now we should be thankful for the better brain imaging technology because with the help of these Technologies now we are able to explore this amazing structure which is known as the insula.

What exactly is insula?

Insula is enigmatic and to understand this structure, it is first important to understand the anatomy of a brain. It is a known fact that all the mammals have a cerebral cortex.

This, cerebral cortex makes the outermost layer of the brain and this layer is relatively newer than the other layers of the brain.

Because of the Brain imaging Technologies now we are aware of the fact that this amazing layer which is called the cerebral cortex is related with intellectual processes like cognition, emotions, Complex behaviours and complex thoughts.

The Bizarre location of insula 

It’s time to explore the location of insular cortex and for that, we have to go deeper into the cerebral cortex. There is an organ which is known as lateral sulcus. This organ which is located inside the cerebral cortex is also known as Sylvain fissure.  

What does Sylvain fissure do? This particular region of the brain basically separates the frontal, parietal and temporal lobes of the brain but we are more concerned about the location of insular cortex.

To be precise insula is located inside the Sylvain fissure. It is so deep in the fissure that it was almost impossible for scientists and researchers to get to know this amazing region but now thanks to the amazing brain Technologies, we know about insula.

The neurologist who changed the course of insula?

It was very difficult to get to know about insula but Antonio Damasio changed it all. He is a famed neuroscientist and he was the one who first said that insular cortex or insula basically plays an important role in mapping somatic states.

He was the one who provided first-hand information about insula and after him many neuroscientists worked on it. Now the Neuroscientists divide insula into two distinct regions; one is the large anterior insula and the other is small posterior insula.

Ironically, the small posterior insula is further subdivided into many great parts.

What is the function of insula?

Insula is a tiny structure but it performs a very important function. Insula provides an emotional cognition to physiological experiences. For example, if there is pain in any part of your body then it is insula which cognise this pain as an unpleasant feeling.

Imagine a world where you could not know what is happening to your body. It is because of insula that you know how to react when your body is experiencing different emotions.

Any damage to insula would mean that you won’t be able to differentiate between different emotions and it is a very bizarre feeling.

Let’s talk about the different functions of Insular cortex

  •  Insular cortex helps us in the perception of pain. For instance if you hurt your big toe then it is insula who will tell you that you are experiencing pain.
  •  Insula helps us enjoy the basic emotions ranging from happiness, Joy, anger and disgust. Without the help of insular cortex we won’t be able to experience these basic emotions.
  •  On the bad side, insula is responsible for addictive habits. All those who are the victims of obsessive-compulsive disorders may have some damage in insular cortex.
  •  If you are able to consciously know about your bodily states then it is happening because of insula. For instance, if you know that your heart is beating then you are having this perception because of insular cortex. On the other hand, if you know that your body is feeling heat then that is also because of insula.
  •  Insular lobe helps in motor control to a certain extent.
  •  Insula is also philosophical in nature. It is because of insular cortex that we are having the perception of self and I am.
  •  Most of the time we are able to read our own emotions and we are having this perception because of insula.

VENs Neurons In Insularly Lobe

There are VENs neurones in insula which are long and cigar-shaped. These particular neurones are responsible for the formation of social relationships. If we are able to read social cues, it is because of these amazing neurones.

VENs also play a greater role in the social development of apps along with humans. It is because of these neurones that we have a sense of self and we know that we are human.

It is because of these neurones that we enjoy social skills which differentiate us from the other mammals.

Insula and limbic system

Insula is dependent on the other regions of the brain for its proper functioning and it makes a strong connection with limbic system. There are number of structures in insula cortex which magically connect with limbic system for sending signals.

It is a fact that limbic system plays an important role in memory, learning and motivation because it has amazing structures like amygdala and hippocampus. Insula is directly connected with limbic system and together, these two structures make the brain much more functional.

In case some damage happens to limbic system then it is a sure thing to say that the insula will also be affected. In most severe cases trauma in the limbic system can lead to a trauma in insula which can lead to mental illness.

People who enthusiastically engage in gambling and compulsive behaviours are said to have been suffering because of some damaging in limbic system.

How a damaged insula can affect the functioning of the brain?

Insula is the vital part of brain and location damage happened to insula then the results can be very catastrophic.  

Sometimes there is a possibility that brain will find an alternative way to function properly but most of the times without the help of insula brain starts acting bizarre.

Let’s talk about what will happen in case there is damage to the insular cortex.

  • In case of damage to the insula, people will have difficulties with sensory perceptions. For instance there is a possibility that they won’t be able to differentiate and feel touch. Damage to insula mean people won’t be able to taste and smell anything.
  • We are aware of our body because of insular cortex. In case there is damage to insula we won’t be able to be aware of our body at all.
  •  In case insula is damaged, then there are chances that you won’t feel pain at all or you may start feeling pain without knowing its actual source.
  •  People who have a damaged insula are hard-core addicts. If you see someone gambling or drinking to their fill, then know that there is some problem with their insula cortex.
  •  A damage to insula means difficulty in the perception and speaking of languages.
  •  In case the productivity of insula is hampered then there will be emotional imbalance. People with emotional imbalance do not know how to act properly in states of disgust, anger, joy and happiness.
  •  People who have a damaged insula can be the victims of mental illness.
  •  If insula is damaged in children then they can experience developmental delays.
  •  If insula is not working properly then people won’t be able to form successful social relationships. To form successful relationships it is very important that insula works properly.

Summary

  •  Insula is an enigmatic structure of the brain and it is located in the Sylvain fissure.
  •  It was Antonio Damasio who first hypothesize about insular cortex. He was the one who said that insula was responsible for basic functions of cognition and bodily awareness.
  •  Insula plays a number of functions for the proper functioning of human body.
  •  It is because of insula that people are able to perceive pain.
  •  It is because of insula the people have the awareness about their body and self.
  •  The VENs neurones in insula are responsible for our successful social relationships.
  •  Insula makes a very fruitful connection with the limbic system of brain.
  •  Any damage to insula cortex will make it difficult for the brain to function properly.
  •  Without the help of insula, humans are unable to perceive pain and feel joy and happiness.

Reference

  1. MUFSON, E; MESULAM, M; PANDYA, D (1 July 1981). “Insular interconnections with the amygdala in the rhesus monkey”. Neuroscience. 6 (7): 1231–1248. doi:10.1016/0306-4522(81)90184-6PMID 6167896.
  2. ^ Craig AD, Chen K, Bandy D, Reiman EM (2000). “Thermosensory activation of insular cortex”. Nat. Neurosci. 3(2): 184–90. doi:10.1038/72131PMID 10649575.
  3. ^ JAKAB, A; MOLNAR, P; BOGNER, P; BERES, M; BERENYI, E (1 Oct 2011). “Connectivity-based parcellation reveals interhemispheric differences in the insula”. Brain Topography. 25 (3): 264–271. doi:10.1007/s10548-011-0205-yPMID 22002490.
  4. a b c Johannes Sobotta. “Sobotta’s Atlas and Text-book of human anatomy 1909”. p. 145. Retrieved November 10, 2013.
  5. ^ “Definition: ‘Circular Sulcus Of Insula'”. MediLexicon. Retrieved 2012-03-30.
  6. ^ Bauernfeind A; et al. (April 2013). “A volumetric comparison of the insular cortex and its subregions in primates”. Human Evolution. 64 (4): 263–279. doi:10.1016/j.jhevol.2012.12.003PMC 3756831PMID 23466178.