Insula

Original Editor - Lucinda hampton

Top Contributors - Lucinda hampton, Tony Lowe and Vidya Acharya  

Introduction[edit | edit source]

The insula (latin for "island) is a small region of the cerebral cortex located deep within the lateral sulcus, which is a large fissure that separates the frontal and parietal lobes from the temporal lobe.[1] The insular is still poorly understood and is a hidden structure located deep in the human brain.[2] Brain imaging technology now enables us to be able to explore this amazing structure.[3]

  • The insula is important for gustatory and sensorimotor processing, risk-reward behavior, autonomics, pain pathways, and auditory and vestibular functioning.[3] It is because of insula that people are able to perceive pain and have the awareness about their body and self.[3]
  • The Insular is located adjacent to several critical structures, and pathology originating from this area may risk significant neurological morbidity and even mortality.[2]

Function[edit | edit source]

The insula is at least partly responsible seemingly disparate things because it facilitates our concept of self-awareness. This would include the awareness of our bodies and emotions, and how they interact to create our perception of the present moment. This sounds very metaphysical, and is only a hypothesis, but it would help to explain why the insula seems to be involved in such a diversity of thoughts and behaviors.[2]The 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 link with limbic system for sending signals.

The insula helps us in the perception of pain. eg if you hurt your big toe then it is insula who will tell you that you are experiencing pain. The 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. eg, 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 insulam[3]

Functional magnetic resonance imaging (fMRI) has observed three major functional subdivisions with regard to neural circuitry (dorsal-anterior, ventral-anterior, and mid-posterior). The anterior part connects to more anterior structures related to emotional integration, and the posterior part connects to more posterior structures related to cognition.[2]

Mindfulness[edit | edit source]

The greatest impact of mindfulness is its effect on the neural plasticity of the brain. Several changes in brain activation have been documented with mindfulness practice, allowing us to also “see” the benefits of MBI as is evident on functional Magnetic Resonance Imaging (fMRI).[4]

  • Studies suggest that mindfulness induces structural connectivity changes beyond intensive physical fitness and cognitive training.
  • The gain in insula connection strength following mindfulness training indicates an increase in the capacity to perceive internal experience. Those who benefit most from mindfulness have either high levels of stress or psychopathology.[5]

Concluding Remarks[edit | edit source]

The insula remains one of the least understood cortical structures of the human brain. Given its deep location and involvement in many neural circuits, there is an impetus to continue improving our understanding both through clinical and translational studies.

New and improved diagnostic technologies eg electroencephalogram (medical test used to measure the electrical activity of the brain), fMRI, Diffusion tensor imaging (a newly developed magnetic resonance imaging (MRI) technique that analyzes the anatomy of nerve cells and a complex neuronal network of the brain[6]), machine learning, and brain-computer interfaces (BCI) may elucidate the anatomic and functional characteristics of the insula to improve outcomes for patients.[2]

References[edit | edit source]

  1. Neuroscientifically challenged Insula Available:https://www.neuroscientificallychallenged.com/blog/2013/05/what-is-insula (accessed 8.8.2021)
  2. 2.0 2.1 2.2 2.3 2.4 Kortz MW, Lillehei KO. Insular Cortex. [Updated 2021 May 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available:https://www.ncbi.nlm.nih.gov/books/NBK570606/ (accessed 8.8.2021)
  3. 3.0 3.1 3.2 3.3 The Human Memory Insula Available:https://human-memory.net/insula/ (last accessed 8.8.2021)
  4. Mindfulness
  5. Sharp, P.B., Sutton, B.P., Paul, E.J. et al. Mindfulness training induces structural connectome changes in insula networks. Sci Rep 8, 7929 (2018). Available:https://www.nature.com/articles/s41598-018-26268-w/?sf192114460=1#citeas (accessed 8.8.2021)
  6. News medical DTI Available: https://www.news-medical.net/health/Diffusion-Tensor-Imaging-(DTI)-Explained.aspx (accessed 8.8.2021)