Hi. Take a smile. To kiss. Classes. Eat. All of these actions have at least one thing in common: they require some sort of movement on the part of the subject to occur. The ability to move is fundamental for survivalAs it allows us to react to stimuli and actually perform any type of behavior, including those necessary for our survival. But the movement is not without more, it takes a little planning, coordination and precision.
At the level of the brain, this control it is carried out mainly by the motor cortex of the brain, Although it is also influenced and mediated by other brain structures. Throughout this article, we can see what the motor zone is, where it is located and what parts are made up of, as well as some of the main issues that arise from injury.
Motor cortex of the brain: location and functions
This part of the cerebral cortex is called the motor or motor zone of the brain, the main functions of which are to allow the generation, maintenance and completion of voluntary and conscious movements by the subject.
This brain region is located in the upper and rostral part of the brain, behind the frontal lobe, located just before the central slit or Rolando and the somatosensory area. It is in this area that Penfield’s motor homunculus is represented, a representation which indicates parts of the cortex that focus on the movement of certain muscles among which stand out some especially innervated such as the hands, the tongue or the face.
Major regions of the motor area of the brain
In the motor cortex we can find different regions, all of which are of great importance when it comes to managing movement. Among them, the main ones are as follows.
1. Primary motor cortex
The main structure in charge of movement is the area that will generate and send the order of movement to all the voluntary muscles of the body. It is the part of the brain that sends the order to the muscles to contract or to stretch., Generate movement.
The primary motor cortex does not function on its own, but needs information about the following areas in order to plan and work out movements. In the primary motor cortex are, among others, Beltz cells. These long cells, which will cross the spinal cord to synapse with other motor neurons.
2. Secondary motor cortex
This zone plays an important role in the programming and planning of the movements and sequences to be followed in order to be able to perform the movements in a precise and coordinated manner. Despite this and the fact that the electrical stimulation of these areas can produce movement, it is not in itself the one who is dedicated to performing them, but focuses on organize the movement before the primary motor can do it.
To make a movement, it will first be necessary to act on these zones, then to be able to transmit the information to the primary motor zone and once there send the movement order. It is very much related to the areas of association. In the secondary motor zone we can find two regions of great importance.
2.1. premotor zone
Located in the motor cortex, in front of the primary motor cortex and near the Silvio cleft, The premotor zone or cortex is found. This area is particularly linked to the programming and guiding of movements, by storing the motor programs learned by experience. This also includes the movement necessary for speech. It generally acts on these motor responses guided by an exogenous stimulus.
2.2. Additional driving zone
As part of the secondary motor cortex, the supplementary motor area is associated with the planning, programming and coordination of complex movements, as well as the initiation of movement. It also participates in aspects such as adopting postures and in addition it has an influence on uncoordinated movements.
3. Drill area
In different classifications, it is included in the Broca zone in the motor areas of the brain, because allows language production and the muscle movement required for it. It is located on the edge of the additional engine area.
4. Association zones of the posterior parietal cortex
In some classifications, this area appears as one of the motor areas, because transforms visual and sensory information into motor instructions.
Associated problems and disorders
As noted above, the motor cortex is a region of the brain of great importance for being able to perform virtually any action. This is why damage to these areas of the brain can have serious repercussions on the lives of patients.
Paralysis is one of the problems that can cause injury or destruction of the cortex or motor area. and loss of mobility, whether in a specific part of the body, in a hemisphere or throughout the body. Hemiplegia or quadriplegia can occur. If the lesion is alone in one hemisphere, the paralysis will occur contralaterally: that is, if the right motor cortex is injured, the left hand will be paralyzed.
As for secondary motor areas, the effects of injury on them often impair the ability to perform movements in a coordinated and sequential manner. We talk about the appearance of possible apraxia, aphasia or dysarthria when we talk about problems in the production of the movements necessary to communicate. Stapling may also occurNot being able to perform correctly the movements necessary for writing, food or even visual problems when it does not properly regulate the movement of the organs and muscles of the face.