The brain is located in the cavity of the skull. It consists of 5 divisions: the medulla oblongata, posterior, middle, intermediate and terminal, also called the large hemispheres.
Upper ventral surface (oblongthe brain, as well as other departments) corresponds to the inner concave part of the skull. On the other hand, the lower surface, which is the base of the brain, has a complex structure that corresponds to the cranial fossa in this place.
We will understand in detail, from which the surface of the hemispheres of the brain is formed.
The final brain includes two hemispheres, separatedfrom each other by a longitudinal slit. In the depths they are connected by a corpus callosum and spikes. The brain consists of left and right lateral ventricles, located in one and the other hemispheres. Outside, the surface of the cerebral hemispheres is formed by a bark, called "cloak." The cloak is deeper than the white and gray matter. The boundary between the intermediate and final brain is located where the inner capsule is adjacent to the thalamus from the lateral side.
The bark, from which the surface of the cerebral hemispheres is formed, is a thin gray plate. The hemispheres consist of the following parts:
Each of the surfaces is divided by its edges:
The protruding sections are called:
The surface of the cerebral hemispheres has a complex structure, with a large number of furrows and convolutions of various sizes, shapes and directions.
In the anterior parts of the brain are frontal lobes,terminating with the frontal pole and bordering the lateral furrow at the bottom and the central furrow from behind. The latter is in the frontal plane, starting from the medial surface and dissecting the upper edge, it descends downward, not reaching the lateral furrow.
This part is behind the parietal-occipitalfurrows, whereby the upperlateral surface of the cerebral hemisphere continues. Other shares are smaller in size than this. It has very diverse furrows and gyrations and ends with the occipital pole.
From the back side of the central furrowthe parietal lobe is located. On the one side, the parietal-occipital furrow appears on the border, which is located on the medial surface. It dissects the hemisphere from above and passes to the upper-lateral surface.
This part is located on the lower sections on the sideshemispheres. On the one hand, it is divided by the frontal, and on the other side by the parietal lobe by means of a deep lateral sulcus. The edge that covers the islet fraction is called the temporal lid. At the top, the temporal lobe has a temporal pole. Two furrows are distinguished on the side, which are almost parallel to the lateral groove. The gyrus extends roughly along the furrows.
This fraction is located inside the lateral sulcus.It becomes noticeable if you remove parietal, frontal and temporal lobes or move them apart. Its circular furrow separates from all other parts. The surface of the island has a different length of gyrus. Between that which is located behind, and located at the bottom and in front is the central furrow of the islet. And on the lower front there is a small thickening without any furrows, which is called the threshold of the islet.
The medial surface of the brain is formedall shares, except for the islet. A furrow is located above the corpus callosum. It is directed forward and down. Above it is a waist furrow, which originates from the beak of the corpus callosum, is directed upwards, and then turns back, parallel to its furrow. It ends higher from the roller in the form of an under-teat groove. Here, from the waist furrow, the edge, directed upward, branches off.
Medial surface of the superior frontal gyrusIt is located in front of the upper edge of the central furrow. Between the anterior and posterior edges is the anterior margin, which refers to the parietal lobe.
The surface of the cerebral hemispheres is formedin the lower part is quite difficult. Its anterior sections consist of a frontal lobe. Behind the temporal pole. The lower parts of the occipital and temporal lobes belong to this surface.
From below the frontal lobe, at the same level alonglongitudinal slit is the olfactory groove, at the base of which the olfactory tracts and the bulb lie, passing into a triangle. In it, the lateral and olfactory striae are distinguished. Part of the frontal lobe between the olfactory groove and the longitudinal slit is called the straight gyrus. The site on the side of the olfactory sulcus is divided by the ophthalmic furrows into orbits of various shapes and sizes.
The lower surface of the brain behinddiffers by the collateral furrow, which is lateral and below the lingual gyrus on the temporal and occipital lobes. A nasal furrow, confined to the para-hippocampal gyrus, lies a little further from the end of the collateral furrow. The medial occipital-temporal gyrus is located somewhat laterally collateral. Between her and the lateral occipital-temporal gyrus situated nearby is an occipital-temporal groove. But the boundaries here are the lower-latitudinal edge of the hemisphere.
Separately, it should be said about those sites thatare mainly on the medial surface and are formed through emotions, motivational behavior, sleep and other things. They are called the limbic system. The reactions here are created through the original olfactory functions. Because of their morphological basis are those areas that come out of the lower-lateral parts of the cerebral bladder, called the olfactory brain.
The limbic system consists of olfactorytracts, an onion, a triangle, an anterior perforated substance located on the lower surface of the frontal lobe, and other components. Inclusion of these sites became possible due to the similar structure, mutual relations and similarity of many reactions.
From the article we learned from what surfacethe brain is formed. It is important to know that the human brain, having characteristics similar to all of humanity, nevertheless is very different in different people. The same applies to its surface. It is different in representatives of both sexes, ethnic groups and even family members.
