The red nucleus is a very specific structure of the brain related to movement, very prominent and formed by a large group of nerve cells.
Although some of the functions it performs are known, it is a structure that is still partially unknown and is still the subject of research today. In this article we will know the most famous functions, their characteristics and the effects that it produces in case of injury.
What is the red nucleus of the brain?
This core is part of the roof. The tegmentum, on the other hand, is located in another larger area, the midbrain. And the midbrain, in turn, is part of the brainstem or brainstem.
The tegmentum is an area of the brain located in the brainstem, Composed of 5 structures, including the red nucleus.
More specifically, it includes: periaqueductal gray matter (related to defense behavior and pain inhibition), ventral tegmental area (related to strengthening), red core (related to movement), substantia nigra (also related to movement) and brain peduncles (which coordinate eye movements with the head and neck).
In turn, the red nucleus is divided into two zones: paleorubre and neorubre. It has two parts, a lower magnocellular and an upper parvocellular.
Functions of this part of the brain
The red core it is involved in the control of muscle tone, and inhibits muscle contraction responsible for tone. In addition, it participates in the control of the motor skills of the distal muscles of the arm and the proximal muscles of the legs. On the other hand, it participates in the motor coordination of the shoulder and the upper arm.
Another function of the red nucleus is that it helps babies crawl as they learn to crawl. Outraged, is responsible for the swinging motion of the arms when we walk. Even some hand movements are also partially controlled by the red core.
On the other hand, the red core it acts as a relief center for the cerebellar and striated reflex pathways, And plays an important role in the extrapyramidal cortical pathways.
with the animals
It is known that in animals lacking an important corticospinal tract (involved in the control of voluntary movements), the red nucleus is involved in the way they walk. Additionally, it is believed that some animals other than humans make more use of this brain structure. This is due to the fact that in humans, the corticospinal tract is more dominant.
Characteristics and anatomy
The color of the red core is a pink color that can be seen in fresh brain samples. In addition, as we have seen, it is made up of a large group of cells (a kind of mass).
This mass of cells is located in the mesencephalic roof area of the midbrain, Which extends from the substantia nigra (linked to dopamine synthesis) to the cerebral aqueduct (which contains cerebrospinal fluid). Specifically, it is located dorsally to the substantia nigra. Inside there is a rubrospinal tract, which passes through the same nucleus by axons.
However, even with certain things known, much of how the red nucleus works in humans is unknown.
There is another structure related to movement and the red core, the rubrospinal tract (Fibers born in the red nucleus). This one is more specialized in the movement of large muscles (like the arms), unlike the red core, which has more control over the hands.
Fine motor skills (fine control of the fingers), on the other hand, depend on another related structure, the corticospinal tract, linked to specific and voluntary movements. Axons of the red nucleus (most of the time) do not project into the spinal cord, but they do they transmit information to the cerebellum, Coming from the motor cortex.
Injuries and associated disorders
What happens if the red nucleus of the brain is injured? Muscle hypertonicity (increased muscle tone) may appear, leading to stiffness in the body.
A roof injury can also include the red core; in these cases, motor skills are impaired. Some symptoms that may appear are involuntary tremors, Especially in the hands and arms.
Lesion of the areas of the brain responsible for controlling, coordinating and managing movements (in addition to the red nucleus), it involves a number of major motor disorders. However, the causes behind this type of disorder are very varied and can go beyond what was initially discussed.
There are two types of motor disorders: pyramidal (involving paralysis) and extrapyramidal (involving difficulty or alterations in the efficiency of movement). At the psychological level, it is the latter that have the most to do with the field of neuropsychology.
In extrapyramidal disorders there is interference in the execution of movements and reflexes. This can lead to loss of fluidity and efficiency in motor activities.
In turn, extrapyramidal disorders can be of three types:
- Rhythmic: tremors.
- Non-rhythmic and stereotypical: tics and stereotypes.
- Non-rhythmic and non-stereotypical: spasms, convulsions, dystonia, dyskinesias, akathisia, etc.
these troubles they are linked to damage to certain areas of the brain, such as the basal ganglia. They are also closely related to dopamine (deficiencies of this substance) in the neostriatum and damage to the subthalamic nucleus.
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