Cerebral Peduncles: Functions, Structure And Anatomy
The human brain It is such a complex organ that to function correctly it must involve a large number of parts and structures in its anatomy. Several of these parts of the brain are large and easy to distinguish with the naked eye, such as the frontal lobes, but others are very small and are located below these surface folds.
This is the case of the cerebral peduncles, small regions of the brain that, despite their size, are very important. Below you will be able to learn more about these anatomical structures.
The human brain is roughly made up of two main types of “material”: gray matter and white matter. The first is the one that contains a greater concentration of neuronal somata “that is, of “bodies” of neurons, the area in which the nucleus of these cells is located), while in the areas with white matter other anatomical areas of the neuron: the axons, narrow and elongated elements that when grouped in the form of bundles form nerve fibers.
The cerebral peduncles are two small structures of cylindrical shape and white color which are composed of white matter. They arise from the brain stem, specifically above the pons, and reach the cerebral cortex, projecting vertically.
Between the peduncles of the brain is the interpeduncular fossa, a space that acts as a physical separation between these two structures as if it were a kind of tunnel. Besides, the ventral and dorsal sides of each peduncle are separated each other by a sheet of something that is not white matter, but something known as black matter.
It is easy to believe that the cerebral peduncles are the same as the cerebellar peduncles, but this is not the case. These second structures have a similar function, since they also function as important nervous pathways that collect information from various regions. However, both their location and the type of information that these neuronal signal conduits integrate are different.
Functions of the cerebral peduncles
The cerebral peduncles are fundamentally “highway” for nervous impulses that travel through the brain. As they are made of white matter, this information passes through them quickly, since the myelin that covers the axons (and that gives these structures their white hue) makes these electrical signals go at high speed.
The main function of the cerebral peduncles, then, is to communicate two areas of the brain: the midbrain (located at the top of the brain stem) and the cerebral cortex. In fact, these nerve fiber conduits reach the division that is created between the two cerebral hemispheres.
In fact, the peduncles contain several pathways. One of them is the corticospinal nerve, which, as its name indicates, connects the cortex with the spinal cord, and the other is the corticopontine tract which connects the cortex with the Varolio bridge.
As the brain stem is responsible for executing automatic and stereotypical actions useful or necessary for our survival, the role of the cerebral peduncles also has to do with this task.
Thus, the main functions of these bundles of nerve fibers are regulation of motor impulses and the transmission of reflex actions, two very useful mechanisms to keep us alive, since they allow us to react quickly to significant events (especially if they are dangerous or harmful).
Specifically, the peduncles play an important role in the reflex eye movements necessary for them to function well, and in the coordination of these acts with other movements of the head and neck.
Specifically, these structures are involved in the reflex control of reflex movements. Normally this occurs when the orders from the motor cortex reach the cerebral peduncles, and from these they go to several nuclei of a structure known as the thalamus, located deep in the brain, in an area known as the diencephalon.
Parts of this pair of structures
The cerebral peduncles receive connections from the cerebellum, cerebral cortex, and lower areas of the brainstem and spinal cord.
On the other hand, The cerebral peduncles are composed of several parts or sections One of them is the tegmentum of the midbrain, which is succeeded by the cerebral crus, and the other region is called the pretectum. The tectum extends beyond the brain stem, reaching the cerebral cortex.
The complexity of the different components of the peduncles has to do with the fact that they are located in an area of the central nervous system in which all types of control and coordination functions of specialized actions are carried out and created by millions of years of evolution and natural selection. In little space, the brain stem has tiny areas responsible for carrying out such vital actions as regulating the heartbeat or controlling body temperature.
