Motor cortex of the brain: parts, location, and functions.

These brain areas are responsible for processing information related to Muscle movement.

Say hello. Smile. Kiss. Run. Eat. All of these actions have at least one aspect in common: they require some kind of movement on the part of the subject in order to be carried out. The ability to move is fundamental for survival, since it allows us to react to stimuli and toIt allows us to react to stimuli and actually perform any type of behavior, including those necessary to enable our survival. But movement does not just happen, it requires a certain amount of planning, coordination and precision.

At the level of the brain, this control is mainly carried out by the cortex of the brain. is carried out mainly by the motor cortex of the brain, although it is also influenced by the motor cortex.but it is also influenced and mediated by other brain structures. Throughout this article we can see what the motor area is, where it is located and what parts it is composed of, as well as some of the main problems that are generated when it is injured.

Motor cortex of the brain: location and functions.

It is denominated motor or motor area of the brain to that part of the cerebral cortex whose main functions are those of allowing the generation, maintenance and termination of voluntary and conscious movements on the part of the subject.

This cerebral region is located in the superior and rostral part of the brain, in the posterior part of the frontal lobe, just before the central fissure or Rolando's fissure and the somatosensory area. It is in this area that Penfield's motor homunculus is represented, a representation that indicates the parts of the cortex the parts of the cortex focused on the movement of specific muscles. among which some are particularly innervated, such as the hands, the tongue or the face.

Main regions of the motor area of the brain

Within the motor cortex we can find different regions, all of them of great importance when it comes to managing movement. Among them, the main ones are the following.

1. Primary motor cortex

The main structure in charge of movement, this is the area that will generate and send the movement order to all the voluntary muscles of the organism. It is the part of the brain that sends the order to the muscles to contract or tense, generating movement.generating the movement.

The primary motor cortex does not work alone, but requires information from the following areas in order to plan and elaborate the movements. In the primary motor cortex are found, among others, the Beltz cells. These cells of great length, which will go through the spinal cord to make synapses with other motor neurons.

2. Secondary motor cortex

This area plays an important role in programming and planning the movements and sequences to be followed in order to be able to perform movements in a precise and coordinated manner. Despite the fact that electrical stimulation of these areas can produce movement, it is not in itself the one that is dedicated to making them, but it is focused on organizing the movement before the primary motor can carry it out.

In order to carry out a movement, it will be necessary first of all the action of these areas, in order to be able to pass the information to the primary motor area and once there, the movement order is sent. They are closely connected to the association areas. Within the secondary motor area we can find two regions of great relevance.

Premotor area

Located in the motor cortex, in front of the primary motor cortex and near the Sylvian fissure, is the premotor area or cortex.is the premotor area or cortex. This area is especially linked to the programming and guidance of movement, storing motor programs learned through experience. This also includes the movement necessary for speech. It usually acts in those motor responses guided by an exogenous stimulus.

2.2. Supplementary motor area

Part of the secondary motor cortex, the supplementary motor area is associated with planning, programming and coordination in complex movements, as well as with movement initiation. It also participates in aspects such as posture adoption and also influences uncoordinated movements.

Broca's area

In different classifications, Broca's area is included among the motor areas of the brain, since it allows the production of language. production of language and the and the muscular movement necessary for it. It is located at the border of the supplementary motor area.

4. Association areas of the posterior parietal cortex

In some classifications this area appears as one of the motor areas, because it transforms visual and other sensory information. transforms visual and other sensory information into motor instructions..

Related problems and disorders

As we have indicated above, the motor cortex is a brain region of great importance when it comes to being able to carry out practically any action. That is why an injury in these brain areas can have severe repercussions in the life of patients.

One of the problems that can generate the injury or destruction of the cortex or motor area is paralysis and loss of mobility, either in a particular part of the body, in a hemibody or in the whole body. and loss of mobility, either in a specific part of the body, in a hemibody or in the whole body. It is possible that hemiplegia or tetraplegia may appear. If the lesion is only in one hemisphere, paralysis will occur contralaterally: that is, if the right motor cortex is injured, the left hand will be paralyzed.

Regarding the secondary motor areas, the effects of a lesion in them usually alter the ability to perform movements in a coordinated and sequential manner. We are talking about the emergence of possible apraxias, or aphasia or dysarthria when we refer to problems in the production of the movements necessary to communicate. It can also produce agraphiaIt can also cause agraphia, as the necessary movements for writing cannot be performed correctly, feeding problems or even visual problems as the movement of the facial organs and muscles is not correctly controlled.