Our nervous system is an inexhaustible source of curious facts. The lenticular nucleus is one of them. It is a subcortical brain structure that has among its functions that of being the architect of the motivation for learning. Yet when we speak of the lenticular nucleus, we are not referring to a specific structure, but to a set of brain structures.
In this article we present the parts, features and functions associated with this core. We will also illustrate the most common alterations and their consequences. Finally, we will also introduce some curious data on the lenticular core. let’s begin!
What are the parts of the lenticular nucleus?
The name of this area of the brain comes from its lens shape. It is located under the insula and is made up of three segments, which are divided mainly into two structures (from the text Neuroscience. Exploration of the Brain, Bears, Connors & Paradiso):
- Putamen. (from the Latin putamen , “nutshell”) It is a circular structure, and constitutes the outermost part of the nuclei. It is connected to the substantia nigra and the pale globe, which facilitates the conduction of information between the basal ganglia, the cerebral cortex and the thalamus.
- Pale globe. Also known as paleostriatum. It is divided into two parts: external, or lateral, and internal, or medial. It receives information from the corpus striatum and sends it to the thalamus and, through it, to the cerebral cortex. It consists of internal and external segments.
We can say that the lenticular nucleus is the union of two structures. It consists of gray matter, is uniform and is attached to the inner and outer capsules. In this area of the brain there are mainly the neurotransmitters GABA, acetylcholine, and the enkephalin peptide. But, besides the lenticular nucleus, what are the other parts of the basal ganglia?
- Striated body.
- Substancia nigra.
- Nucleus caudate.
- Nucleus accumbens.
- Subthalamic nucleus.
These ganglia are a collection of interconnected nuclei found around the limbic system and the third ventricle. Their functions are associated with planning, integration, movement control, learning and motivation. Recall that, although there are anatomical divisions in every part of the brain, none participate in a single function.
The functions of the lenticular nucleus
Its functions are different. Let’s see the main ones:
- Motivation. It integrates information, allowing knowledge to be linked to stimuli received from the outside. Incredible, right?
- Learning. It is mainly associated with learning procedures. It also intervenes in the categorization mechanism, facilitating the organization of information. Therefore participate in the acquisition and improvement of our skills.
- Movement. This area controls the automation of movements, which intervenes in various mechanisms, such as habit. It also participates in maintaining posture and coordinating movement. The putamen also controls the movement of the muscles of the face and extremities.
To perform these functions, the lenticular nucleus establishes connections with the cerebral cortex and with the thalamic nuclei. This communication can be two-way.
Disorders associated with the malfunction of this structure
This area of the brain can be involved in some forms of subcortical dementia. Examples are those produced by Parkinson’s disease and Huntington’s chorea, associated with the inability or difficulty to coordinate and perform movements, whether in a resting position or not, and accompanied by a deficit of executive functions in memory.
It is also associated with psychomotor disorders. For example, Parkinson’s disease specifically affects the basal ganglia. It is also involved in other movement disorders, such as ataxia, Gilles de la Tourette syndrome and other tics.
On the other hand, this core can also be involved in some mental disorders. It has been associated with obsessive-compulsive disorder, since both the caudate nucleus and the putamen are hyperactivated in this pathology. Even in the case of attention deficit hyperactivity disorder there seems to be an abnormal functioning of the lenticular nucleus, since interference in motivation, learning and the appearance of tics are noted.
In summary, the lenticular nucleus is essential for our body. It is involved in very different functions, such as motor function or attention management. It also helps us to better organize and structure information, enhancing our learning skills. Precisely for this reason, its alterations can directly affect our health and our quality of life.