Caudate nucleus: characteristics, functions and disorders.
This component of the human brain is involved in memory and coordination of movements.
When we think of the brain, we usually think of 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 the human being, 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 next..
What is the caudate nucleus?
The caudate nucleus is a subcortical structure, i.e., located inside the brain, which is part of the basal ganglia. part of the basal ganglia. Together with the putamen and the nucleus accumbens it forms the so-called 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 with the rest of the basal ganglia as well as with the frontal cortex and the limbic system. We have two units of this nucleus, each located in one cerebral hemisphere. At the neurotransmitter level, the caudate nucleus is mainly influenced by dopamine and GABA.
The caudate nucleus is usually divided into three partsThe caudate nucleus is usually divided into three parts, the head, the body and the tail. While the head is one of the thickest parts and is in closer 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 ensure both a correct adaptation to the environment and survival by allowing the regulation of behavior through aspects such as memory and motivation. In addition, they have also been linked to a great extent to the coordination of movements..
Below you can find detailed 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 involvement in motor control and coordination. The maintenance of the position of the limbs of the body, and the 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 chorea.
Memory and learning
Learning and memory are elements in which the caudate nucleus has also been found to play an important role. For example, procedural learning depends on this brain area.. Specifically, the caudate nucleus enables the organism to obtain feedback from the outside world about what is happening and what is being done. It also participates in the comprehension of auditory stimuli, such as language stimuli.
3. Sensation of alarm
Another of the main functions of this brain region is the perception of the sensation of alarmthanks to which we can identify that something is not working properly and respond accordingly.
4. Motivation
The caudate nucleus is of paramount importance in terms of the motivational capacity of the human being. It is a structure that connects the limbic connects the limbic system with the frontal cortex, so that cognitive information is transformedIt 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 generate the appearance of extreme abulia and PAP syndrome.
Disorders and alterations in which it participates
The caudate nucleus and in general the basal ganglia as a whole, 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 is involved are the following. 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 particular situation, as well as in the sense of alarm. In OCD this mechanism is overactivatedIt has been found that patients with this disorder usually have an elevated neural activation in the caudate.
In addition to OCD itself, this high level of activity can also be found in other similar disorders such as hoarding disorder, excoriation disorder or trichotillomania.
Attention Deficit Hyperactivity Disorder (ADHD)
ADHD is another disorder in which the caudate nucleus has some level of involvement. Specifically, in this case, activation is observed to be lower than usual, so that the capacity for recall, feedback and motivation are reduced..
3. Huntington's chorea
In Huntington's chorea, the caudate nucleus is one of the first areas to show neuronal death, and eventually leads to a progressive loss of executive and memory functions. a progressive loss of executive and memory functions and uncontrolled movements and the performance of uncontrolled movements in the form of dance-like twisting and turning of body parts.
4. Parkinson
Parkinson's disease is another disease linked to the caudate nucleus. Specifically, Parkinsonian symptoms are caused by the degradation and death of neurons in the caudate nucleus. degradation and death of the neurons that form the nigrostriatal pathway..
5. Loss of psychic self-activation syndrome
Damage to the caudate nucleus causes loss of motivation and hinders the connection between emotion and cognition. This is why its destruction generates a deep sense of indifference whatever happens, even if it threatens one's 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 have an above-average caudate nucleus possess a larger caudate nucleus than most people.
Bibliographical references:
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Carlson, N.R. (2014). Behavioral Physiology (11th Edition). Madrid: Pearson Educación.
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Kandel, E.R.; Schwartz, J.H. & Jessell, T.M. (2001). Principles of neuroscience. Fourth edition. McGraw-Hill Interamericana. Madrid.
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Melnick, M.E. (2013). Basal ganglia disorders. In: Umphred DA, Burton GU, Lazaro RT, Roller ML, eds. Umphred's Neurological Rehabilitation. 6th ed. Philadelphia, PA: Elsevier Mosby; chap 20.
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Packard, M.G. & Knowlton, B.J. (2002). Learning and memory functions of the basal ganglia. Annu Rev Neurosci 25:563-59.
(Updated at Apr 12 / 2024)