Parts and structure of the olfactory brain. Olfactory brain and limbic system. Structure and functions. Transparent septum, hypocampus, fornix, tonsils. Structures of the limbic system
The olfactory brain, rhinencephalon, is phylogenetically the most ancient part of the forebrain, which arose in connection with the analyzer of smell, when the forebrain had not yet become
organ of animal behavior. Therefore, all its components are different parts of the olfactory analyzer.
In fish, almost the entire forebrain is the organ of smell. With the development of the neocortex, which is observed in mammals and humans, a new part of the forebrain develops (
neencephalon) - raincoat, pallidum. But the cloak also goes its long way of development and contains three parts of different phylogenetic age. Older parts:
1. Paleopallum, which is part of the temporal lobe. Initially, this department was located on the lateral surface of the hemisphere, but later, under the influence of a strong
increasing neopallium, it curled up into a sausage-like formation - the hippocampus and shifted medially into the cavity of the lateral ventricle of the telencephalon in the form of its protrusion
lower horn. The hippocampus is covered with an ancient cortex, paleocortex.
2. Archipallium - a small area of the cortex on the ventral surface of the frontal lobe, lying near the bulbus olfactorius and covered with old bark, archicortex.
3. Neopallium, a new cloak, in whose cortex, neocortex, the higher centers of smell appeared - the cortical ends of the analyzer. This is the uncus, which is part of the vaulted
convolutions.
As a result, the human olfactory brain contains a number of formations of various origins, which can be topographically divided into two sections. Peripheral
the department is the olfactory lobe, lobus olfactorius, which means a number of formations that lay on the base of the brain:
1) bulbus olfactorius;
2) tractus olfactorius;
3) trigonum olfactorium;
4) substantia perforata anterior.
Central department are the convolutions of the brain:
1) parahippocampal gyrus, gyrus parahippocampalis;
2) dentate gyrus, gyrus dentatus;
3) vaulted gyrus, gyrus fornicatus, with its anterior part located near the temporal pole - a hook, uncus.
Lateral ventricles
In the hemispheres of the telencephalon lie below the level of the corpus callosum, symmetrically on the sides of the midline, two lateral ventricles, ventriculus lateralis, separated from
the upper lateral surface of the hemispheres throughout the entire thickness of the medulla. The cavity of each lateral ventricle corresponds to the shape of the hemisphere: it begins in the frontal lobe in
in the form of an anterior horn bent down and to the lateral side, cornu anterius from here it stretches through the area of \u200b\u200bthe parietal lobe under the name of the central part, pars centralis which
at the level (in the thickness of the temporal lobe) and the posterior horn, cornu posterius (in the occipital lobe).
The medial wall of the anterior horn is formed by the septum pellucidum, which separates the anterior horn from the same horn of the other hemisphere.
The lateral wall and partly the bottom of the anterior horn are occupied by an elevation gray color, the head of the caudate nucleus, caput nuclei caudati, and the upper wall is formed by fibers
corpus callosum. The roof of the central, narrowest part of the lateral ventricle also consists of fibers of the corpus callosum, while the bottom is made up of the continuation of the caudate nucleus,
corpus nuclei caudati, and parts of the upper surface of the thalamus. The rear horn is surrounded by a layer of white nerve fibers originating from the corpus callosum, the so-called tapetum
(cover); on its medial wall, a roller is visible - a bird's spur, calcar avis, formed by an impression from the side of sulcus calcarinus, located on the medial surface
hemisphere. The upper lateral wall of the lower horn is formed by the tapetum, which is a continuation of the same formation surrounding the posterior horn. From the medial side to
the upper wall is bent down and anteriorly thinned part of the caudate nucleus - cauda nuclei caudati.
Along the medial wall of the lower horn, it stretches throughout white color eminence - hippocampus, hippocampus, which is formed due to depression from deep
cutting outside the sulcus hippocampi. The anterior end of the hippocampus is divided by grooves into several small tubercles. Along the medial edge of the hippocampus goes like this
called fringe, fimbria hippocampi, representing the continuation of the legs of the arch (crus fornicis).
At the bottom of the lower horn is a roller, eminencia collateralis, originating from an impression outside the sulcus of the same name. From the medial side of the lateral ventricle to its
the central part and the lower horn protrude from the pia mater, which forms the choroid plexus in this place, plexus choroideus ventriculi lateralis. The plexus is covered with epithelium,
representing the remainder of the undeveloped medial wall of the ventricle. Plexus choroideus ventriculi lateralis is the lateral border of the tela choroidea ventriculi tertii.
171 173 ..Olfactory brain (human anatomy)
TO olfactory brain, rhinencephalon, include: olfactory bulb, bulbus olfactorius, olfactory tract, tractus olfactorius, olfactory triangle, trigonum olfactorium, anterior perforated substance, substantia perforata anterior, gyrus of the belt, gyrus cinguli, isthmus, isthmus, parahippocampal gyrus, gyrus parahippocampalis, dentate gyrus, gyrus dentatus, and hippocampus, hippocampus.
The gyrus of the girdle, isthmus, parahippocampal gyrus, hippocampus, dentate gyrus, fornix, and amygdala are part of the limbic system. It is believed that this system performs not only an olfactory function, but also has importance in the processes of synthesis of afferent stimuli, emotional reactions and reactions of the so-called innate behavior (sexual, search and defensive). For connections in the system of formations of the olfactory brain, see Pathways of the olfactory analyzer.
Subcortical nuclei (human anatomy)
The subcortical nuclei are located in the white matter of the cerebral hemispheres closer to their base, and therefore these nuclei are sometimes called basal. They form three paired clusters gray matter: striatum, corpus striatum, amygdala, corpus amygdaloideum, and fence, claustrum (Fig. 208).
Rice. 208. Frontal section of the hemispheres, passing through the striatum and thalamus. 1 - vault; 2 - choroid plexus of the III ventricle; 3 - choroid plexus of the lateral ventricle; 4 - lateral ventricle; 5 - caudate nucleus; 6 - posterior leg of the internal capsule; 7 - shell; 8 - pale ball; 9 - outer capsule; 10 - fence; 11 - lateral groove of the brain; 12, 14, 15 - superior, middle and inferior temporal gyrus; 13 - islet; 16 - parahippocampal gyrus; 17 - oculomotor nerve; 18 - bridge; 19 - the core of the nipple body; 20 - visual tract; 21 - III ventricle; 22 - inter-tubercular fusion; 23-25 - nuclei of the optic nerve; 26, 28, 31 - lower, middle and upper frontal gyrus; 27 - corpus callosum; 29 - gyrus of the belt; 30 - groove belt
striatum consists of two nuclei: caudate, nucleus caudatus, and lenticular, nucleus lentiformis.
The caudate nucleus is a rounded formation that surrounds the optic tubercle and the lenticular nucleus in the form of an arc. The sharply thickened, clavate anterior section of the caudate nucleus is called the head, caput nuclei caudati. Posteriorly, the head becomes thinner and forms the body of the caudate nucleus, corpus nuclei caudati, which passes into the tail, cauda nuclei caudati. The head, body and tail are involved in the formation of the walls of the lateral ventricle of the brain.
The lenticular nucleus is a large pyramidal-shaped accumulation of gray matter, which is located outward from the caudate nucleus and thalamus and is separated from them by an internal capsule. The convex outer surface of the lentiform nucleus faces the islet, and the narrowed apex is inward and downward. The lentiform nucleus is heterogeneous in its structure and is divided by plates of white matter into three parts: the outer, dark color - the shell, puta-men, and two light medial ones - the pale ball, globus pallidus. The caudate and lenticular nuclei are the main link of the extrapyramidal system, the main function of which is the implementation of complex unconditioned reflex motor acts.
Fence , claustrum, - a relatively thin plate of gray matter, which is located in the white matter, separating the outer surface, putamen and the cortex of the island. The white matter that separates the fence and the shell is called the outer capsule, capsula externa, and the area of \u200b\u200bwhite matter between the fence and the cortex of the island is called the outer capsule, capsula extrema. The fence is a complex formation, the connections of which have been little studied so far, and the functional significance is not clear.
Topographically, the olfactory brain is divided into two sections: peripheral and central.
TO peripheral department relate:
olfactory bulb, bulbus olfactorius;
olfactory tract, tractus olfactorius;
olfactory triangle, trigonum olfactorium;
Anterior perforated substance, substantia perforata anterior.
Central department:
vaulted gyrus, gyrus fornicatus;
dentate gyrus, gyrus dentatus;
hippocampus, hippocampus.
The main pathways of the olfactory brain form a vault, which begins in the form of narrow fringe of ammonium horn. On each side they rise from the lower horn of the lateral ventricle to splenium corporis callosi and pass into the legs of the vault . The latter converge, forming the body of the vault , which continues anteriorly to the region of the interventricular opening, where it is divided into columns of the fornix . Columns in the form of white cylindrical strands pass in a curved arc in front of the visual tubercle and behind the anterior cerebral commissure plunge into the depths and end in the papillary bodies.
limbic system
The limbic system includes a number of cortical and subcortical formations that form the so-called "hippocampal circle" (Papez circle).
Cortical structures include:
1. Belt gyrus or superior limbic gyrus.
2. Parahippocampal gyrus or inferior limbic gyrus.
3. Hippocampus .
4. Dentate gyrus .
5. Ribbon gyrus .
Among subcortical formations The limbic system includes:
1. Olfactory bulb, tract and triangle.
2. Amygdala .
3. Anterior and medial nuclei of the thalamus .
4. Kernels of the transparent septum .
5. Leash cores .
6. Papillary bodies .
7. Interpeduncular nucleus of the midbrain .
8. Central gray matter of the aqueduct of the brain .
9. A system of conducting paths that provide a connection between these formations, and the main conducting path is the vault.
The limbic system is closely related to the reticular formation of the brainstem both structurally and functionally. Together they are united by the concept limbic-reticular complex.
The entire flow of sensory information from the intero- and exteroreceptors, including the receptor fields of the sense organs, flows into the limbic system. On this basis, here is primary synthesis of state information the internal environment of the body and the factors affecting the body external environment, and are formed basic needs(for example, the need for water and food, self-defense, etc.). These needs are biological motivations (motive - inducement) for a certain type of behavior (for example, searching for food), which is accompanied by a specific emotional coloring. Depending on the achievability of the result, emotions can be both positive and negative. In other words, the eternal irresistible “I want” and the really feasible “I can” collide. Therefore, such behavior, which has a specific biological reason - a motive and a certain emotional coloring, is called emotional and motivational behavior. It is one of the main functions of the limbic system of the brain. The satisfaction of biological needs is aimed at maintaining homeostasis and, consequently, the survival of the biological system. Control of the state of the internal environment is provided by the vegetative and endocrine systems, and limbic system, Thus, provides regulation of vegetative-visceral-humoral relations.
The level of consciousness and, consequently, the activity of motor and mental functions, speech and attention, memory, the state of wakefulness and sleep depend on the state of the limbic system.
Damage to the limbic system leads to pronounced changes in the emotional sphere, vegetative-endocrine disorders, sleep disturbance, and memory. Pathological processes associated with damage to one of the parts of the limbic system lead to severe memory disorders in the form of impaired memorization of current events. Traces of memory disappear after 2-3 minutes. What has just been seen, read, heard is immediately forgotten, while the events of the past, recorded during the period of health, are easily reproduced.
The olfactory brain, rhinencephalon, is phylogenetically the most ancient part of the forebrain, which arose in connection with the analyzer of smell, when the forebrain had not yet become
organ of animal behavior. For this reason, all its components are different parts of the olfactory analyzer.
In fish, almost the entire forebrain is the organ of smell. With the development of the neocortex, which is observed in mammals and humans, a new part of the forebrain develops (
neencephalon) - raincoat, pallidum. But the cloak also goes its long way of development and contains three parts of different phylogenetic age. Older parts:
1. Paleopallum, which is part of the temporal lobe. Initially, this department was located on the lateral surface of the hemisphere, but later, under the influence of a strong
increasing neopallium, it curled up into a sausage-like formation - the hippocampus and shifted medially into the cavity of the lateral ventricle of the telencephalon in the form of its protrusion
lower horn. The hippocampus is covered with an ancient cortex, paleocortex.
2. Archipallium - a small area of the cortex on the ventral surface of the frontal lobe, lying near the bulbus olfactorius and covered with old bark, archicortex.
3. Neopallium, a new cloak, in whose cortex, neocortex, the higher centers of smell appeared - the cortical ends of the analyzer. This is the uncus, which is part of the vaulted
convolutions.
As a result, the human olfactory brain contains a number of formations of various origins, which can be topographically divided into two sections. Peripheral
the department is the olfactory lobe, lobus olfactorius, which means a number of formations that lay on the base of the brain:
1) bulbus olfactorius;
2) tractus olfactorius;
3) trigonum olfactorium;
4) substantia perforata anterior.
The central section is the convolutions of the brain:
1) parahippocampal gyrus, gyrus parahippocampalis;
2) dentate gyrus, gyrus dentatus;
3) vaulted gyrus, gyrus fornicatus, with its anterior part located near the temporal pole - a hook, uncus.
Lateral ventricles
In the hemispheres of the telencephalon lie below the level of the corpus callosum, symmetrically on the sides of the midline, two lateral ventricles, ventriculus lateralis, separated from
upper lateral surface of the hemispheres of the entire thickness of the medulla. The cavity of each lateral ventricle corresponds to the shape of the hemisphere: it begins in the frontal lobe in
in the form of an anterior horn bent down and to the lateral side, cornu anterius from here it stretches through the area of \u200b\u200bthe parietal lobe under the name of the central part, pars centralis which
at the level (in the thickness of the temporal lobe) and the posterior horn, cornu posterius (in the occipital lobe).
The medial wall of the anterior horn is formed by the septum pellucidum, which separates the anterior horn from the same horn of the other hemisphere.
The lateral wall and partly the bottom of the anterior horn are occupied by a gray elevation, the head of the caudate nucleus, caput nuclei caudati, and the upper wall is formed by fibers
corpus callosum. The roof of the central, narrowest part of the lateral ventricle also consists of fibers of the corpus callosum, while the bottom is made up of the continuation of the caudate nucleus,
corpus nuclei caudati, and parts of the upper surface of the thalamus. The posterior horn is surrounded by a layer of white nerve fibers originating from the corpus callosum, the so-called tapetum
(cover); on its medial wall, a roller is visible - a bird's spur, calcar avis, formed by an impression from the side of sulcus calcarinus, located on the medial surface
hemisphere. The upper lateral wall of the lower horn is formed by the tapetum, which is a continuation of the same formation surrounding the posterior horn. From the medial side to
the upper wall is bent down and anteriorly thinned part of the caudate nucleus - cauda nuclei caudati.
Along the medial wall of the lower horn, a white elevation stretches along the entire length - the hippocampus, hippocampus, which is formed as a result of depression from a deep
cutting outside the sulcus hippocampi. The anterior end of the hippocampus is divided by grooves into several small tubercles. Along the medial edge of the hippocampus goes like this
called fringe, fimbria hippocampi, representing the continuation of the legs of the arch (crus fornicis).
At the bottom of the lower horn is a roller, eminencia collateralis, originating from an impression outside the sulcus of the same name. From the medial side of the lateral ventricle to its
the central part and the lower horn protrude from the pia mater, which forms the choroid plexus in this place, plexus choroideus ventriculi lateralis. The plexus is covered with epithelium,
representing the remainder of the undeveloped medial wall of the ventricle. Plexus choroideus ventriculi lateralis is the lateral border of the tela choroidea ventriculi tertii.
Olfactory brain - concept and types. Classification and features of the category "Olfactory brain" 2017, 2018.
Fig.8. Fig.7. IV ventricle Fig.6 Axons of neurons of the reticular formation of the bridge go to the cerebellum, to the spinal cord (reticulospinal path). The latter activate neurons spinal cord. The pontine reticular formation affects the cerebral cortex, causing it to... .
Topographically, the olfactory brain is divided into two sections: peripheral and central. The peripheral section includes: olfactory bulb, bulbus olfactorius; olfactory tract, tractus olfactorius; olfactory triangle, trigonum olfactorium; front perforated... .
The basal nuclei are the massive subcortical nuclei of the telencephalon. These include: striatum, corpus striatum; fence, claustrum; amygdala, corpus amygdaloideum. The striatum consists of the caudate nucleus, nucleus caudatus, and the lentiform, nucleus lentiformis. Front... .
Olfactory brain, its central and peripheral parts. According to modern concepts, in the process of evolution of vertebrates, the sense of smell, based on the olfactory brain, acted as an organizer of integral functions associated with the formation of all unconditionally ... .
1. Lateral olfactory groove - sulcus rhinalis lateralis. 2. Medial olfactory groove - sulcus rhinalis medialis. 3. Olfactory bulb - bulbus olfactorius. olfactory nerve - nervus olfactorius. ventricle - ventriculus bulbi olfactorii. 4. Olfactory legs - pedunculus olfactorius: lateral olfactory ....
Table of contents of the subject "Structure of the cerebral cortex. Olfactory brain. Lateral ventricles. White matter of the hemispheres. Pathways.":
Olfactory brain, rhinencephalon, is phylogenetically the most ancient part of the forebrain, which arose in connection with the analyzer of smell, when the forebrain had not yet become an organ of animal behavior. Therefore, all its components are different parts of the olfactory analyzer (for the concept of the analyzer, see "Morphological foundations of the localization of functions").
In fish, almost the entire forebrain is the organ of smell. With the development of the neocortex, which is observed in mammals and humans, a new part of the forebrain develops. (neencephalon) - raincoat, pallium. But the cloak also goes its long way of development and contains three parts of different phylogenetic age. Older parts:
1. paleopallium, which is part of the temporal lobe. At first, this section was located on the lateral surface of the hemisphere, but later, under the influence of a greatly increasing neopallium, it folded into a sausage-shaped formation - the hippocampus and shifted medially into the cavity of the lateral ventricle of the telencephalon in the form of a protrusion of its lower horn. The hippocampus is covered ancient bark, paleocortex.
2. Archipallium- a small area of the cortex on the ventral surface of the frontal lobe, lying near bulbus olfactorius and covered with old bark, archicortex.
3. Neopallium, a new cloak, in whose cortex, neocortex, higher centers of smell appeared - the cortical ends of the analyzer. This - uncus, which is part of the vaulted gyrus.
As a result, the human olfactory brain contains a number of formations of various origins, which can be topographically divided into two sections. The peripheral department is olfactory lobe, lobus olfactorius, which means a number of formations lying on the basis of the brain: 1) bulbus olfactorius; 2) tractus olfactorius; 3) trigonum olfactorium; 4) substantia perforata anterior.
The central section is the convolutions of the brain: 1) parahippocampal gyrus, gyrus parahippocampali s; 2) dentate gyrus, gyrus dentatus; 3) vaulted gyrus, gyrus fornicatus, with its anterior part located near the temporal pole - crochet, uncus.
