When we think about the brain we usually imagine the superficial and outermost layer, the cerebral cortex. However, beneath this we can find a large number of structures of fundamental importance for the survival of human beings, all of them participating in different types of functions such as the integration of information.
One of these subcortical structures is the caudate nucleus, whose characteristics we will see below
What is the caudate nucleus?
The caudate nucleus is a subcortical structure, that is, located inside the brain, which is part of the basal ganglia Together with the putamen and the nucleus accumbens it makes up what is known as the striatum, an element closely linked to the control of movement.
Located above the thalamus and below the orbitofrontal cortex to later curve towards the occipital lobe, the caudate nucleus connects both with the rest of the basal ganglia and with the frontal cortex and the limbic system. We have two units of this nucleus, each one located in a cerebral hemisphere. At the neurotransmitter level, the caudate nucleus is mainly influenced by dopamine and GABA.
The caudate nucleus is usually divided into three parts , the head, body and tail. While the first is one of the thickest parts and is in more contact with the frontal cortex, the tail is connected to the limbic system. Head and body are in close contact with the lateral ventricles.
Main functions of the caudate nucleus
The caudate nucleus and the set of basal ganglia have a high importance in the human nervous system, participating in essential functions to guarantee both correct adaptation to the environment and survival itself by allowing the regulation of behavior through aspects such as memory and the motivation. Furthermore, they have also been largely linked to the realization and coordination of movements
Below you can find in detail some of the functions that have been attributed to the caudate nucleus.
1. Movement control
Along with the rest of the basal ganglia, the caudate nucleus has traditionally been considered to have a high participation in motor control and coordination Maintaining the position of the body members, and precision in fine movement are some of the aspects in which the caudate participates. This can be seen in the consequences of its dysfunction, in disorders such as Parkinson’s and Huntington’s Korea.
2. Memory and learning
Learning and memory are elements in which the caudate nucleus has also been found to have an important role. For example, procedural learning depends on this brain area Specifically, the caudate nucleus allows the organism to be able to obtain feedback from the outside world regarding what is happening and what is being done. It also participates in the understanding of auditory stimuli, such as those of language.
3. Sensation of alarm
Another of the main functions of this brain region is the perception of the sensation of alarm thanks to which we can identify that something is not working correctly and respond accordingly.
4. Motivation
The caudate nucleus is of capital importance when it comes to the motivational capacity of the human being. It is a structure that connects the limbic system with the frontal cortex , so that cognitive information is transformed and linked to an emotional meaning. Its destruction can cause the appearance of extreme avolition and PAP syndrome.
Disorders and alterations in which it participates
The caudate nucleus and in general the set of basal ganglia, due to their multiple connections with other brain areas such as the orbitofrontal cortex or the limbic system, are structures of great importance for the correct functioning of the nervous system and for our adaptation to the environment. .
The presence of alterations can generate or participate in the genesis or maintenance of various types of disorders. Some of the disorders in which the caudate nucleus participates are the following.
1. Obsessive-Compulsive Disorder and other obsessive disorders
As we have mentioned, the caudate nucleus plays an important role in the response mechanism to a specific situation, as well as in the feeling of alarm. in OCD This mechanism presents an overactivation finding that patients with this disorder usually have high neural activation in the caudate.
In addition to OCD itself, this high level of activity can also be found in other disorders of a similar nature such as hoarding disorder, excoriation disorder or trichotillomania.
2. Attention Deficit Hyperactivity Disorder
ADHD is another disorder in which the caudate nucleus has a certain level of involvement. Specifically, in this case an activation is observed below normal, which means the ability to remember, feedback and motivation are reduced
3. Huntington’s chorea
In Huntington’s chorea, the caudate nucleus is one of the first areas to present neuronal death, and in the long run it ends up generating a progressive loss of executive functions and memory and the performance of uncontrolled movements in the form of twists and turns of the body parts similar to a dance.
4. Parkinson’s
Parkinson’s is another of the diseases linked to the caudate nucleus. Specifically, parkinsonian symptoms are produced by degradation and death of neurons that form the nigrostriatal pathway
5. Syndrome of loss of psychic self-activation
Damage to the caudate nucleus causes loss of motivation and makes it difficult to connect emotion and cognition. That is why its destruction generates a deep sense of indifference Whatever happens, even if it threatens your own survival.
6. Hypermnesia
Although it is not generally considered a disorder, the presence of hypermnesia in some people has been linked, among other brain regions, to the caudate nucleus. Specifically, it has been observed that people with above-average memory abilities They have a larger caudate nucleus than most people.