1-10

http://rgm22.nig.ac.jp/mediawiki-ogareport/index.php/For_Gray_anatomy_normalization


 * The fore-brain or prosencephalon consists of: (1) the diencephalon, corresponding in a large measure to the third ventricle and the structures which bound it; and (2) the telencephalon, comprising the largest part of the brain, viz., the cerebral hemispheres; these hemispheres are intimately connected with each other across the middle line, and each contains a large cavity, named the lateral ventricle. The lateral ventricles communicate through the interventricular foramen with the third ventricle, but are separated from each other by a medial septum, the septum pellucidum; this contains a slit-like cavity, which does not communicate with the ventricles.
 * The Diencephalon.—The diencephalon is connected above and in front with the cerebral hemispheres; behind with the mid-brain. Its upper surface is concealed by the corpus callosum, and is covered by a fold of pia mater, named the tela chorioidea of the third ventricle; inferiorly it reaches to the base of the brain.	  2
 * The diencephalon comprises: (1) the thalamencephalon; (2) the pars mamillaris hypothalami; and (3) the posterior part of the third ventricle. For descriptive purposes, however, it is more convenient to consider the whole of the third ventricle and its boundaries together; this necessitates the inclusion, under this heading, of the pars optica hypothalami and the corresponding part of the third ventricle—structures which properly belong to the telencephalon.	  3
 * The Thalamencephalon.—The thalamencephalon comprises: (1) the thalamus; (2) the metathalamus or corpora geniculata; and (3) the epithalamus, consisting of the trigonum habenulæ, the pineal body, and the posterior commissure.
 * The Thalami (optic thalamus) (Figs. 716, 717) are two large ovoid masses, situated one on either side of the third ventricle and reaching for some distance behind that cavity. Each measures about 4 cm. in length, and presents two extremities, an anterior and a posterior, and four surfaces, superior, inferior, medial, and lateral.	  5
 * The anterior extremity is narrow; it lies close to the middle line and forms the posterior boundary of the interventricular foramen.	  6
 * The posterior extremity is expanded, directed backward and lateralward, and overlaps the superior colliculus. Medially it presents an angular prominence, the pulvinar, which is continued laterally into an oval swelling, the lateral geniculate body, while beneath the pulvinar, but separated from it by the superior brachium, is a second oval swelling, the medial geniculate body.	  7
 * The superior surface is free, slightly convex, and covered by a layer of white substance, termed the stratum zonale. It is separated laterally from the caudate nucleus by a white band, the stria terminalis, and by the terminal vein. It is divided into a medial and a lateral portion by an oblique shallow furrow which runs from behind forward and medialward and corresponds with the lateral margin of the fornix; the lateral part forms a portion of the floor of the lateral ventricle, and is covered by the epithelial lining of this cavity; the medial part is covered by the tela chorioidea of the third ventricle, and is destitute of an epithelial covering. In front, the superior is separated from the medial surface by a salient margin, the tænia thalami, along which the epithelial lining of the third ventricle is reflected on to the under surface of the tela chorioidea. Behind, it is limited medially by a groove, the sulcus habenulæ, which intervenes between it and a small triangular area, termed the trigonum habenulæ.	  8
 * The inferior surface rests upon and is continuous with the upward prolongation of the tegmentum (subthalamic tegmental region), in front of which it is related to the substantia innominata of Meynert.	  9
 * The medial surface constitutes the upper part of the lateral wall of the third ventricle, and is connected to the corresponding surface of the opposite thalamus by a flattened gray band, the massa intermedia (middle or gray commissure). This mass averages about 1 cm. in its antero-posterior diameter: it sometimes consists of two parts and occasionally is absent. It contains nerve cells and nerve fibers; a few of the latter may cross the middle line, but most of them pass toward the middle line and then curve lateralward on the same side.	  10
 * The lateral surface is in contact with a thick band of white substance which forms the occipital part of the internal capsule and separates the thalamus from the lentiform nucleus of the corpus striatum.	  11
 * Structure.—The thalamus consists chiefly of gray substance, but its upper surface is covered by a layer of white substance, named the stratum zonale, and its lateral surface by a similar layer termed the lateral medullary lamina. Its gray substance is incompletely subdivided into three parts—anterior, medial, and lateral—by a white layer, the medial medullary lamina. The anterior part comprises the anterior tubercle, the medial part lies next the lateral wall of the third ventricle while the lateral and largest part is interposed between the medullary laminæ and includes the pulvinar. The lateral part is traversed by numerous fibers which radiate from the thalamus into the internal capsule, and pass through the latter to the cerebral cortex. These three parts are built up of numerous nuclei, the connections of many of which are imperfectly known.	  12
 * Connections.—The thalamus may be regarded as a large ganglionic mass in which the ascending tracts of the tegmentum and a considerable proportion of the fibers of the optic tract end, and from the cells of which numerous fibers (thalamocortical) take origin, and radiate to almost every part of the cerebral cortex. The lemniscus, together with the other longitudinal strands of the tegmentum, enters its ventral part: the thalamomammillary fasciculus (bundle of Vicq d’Azyr), from the corpus mammillare, enters in its anterior tubercle, while many of the fibers of the optic tract terminate in its posterior end. The thalamus also receives numerous fibers (corticothalamic) from the cells of the cerebral cortex. The fibers that arise from the cells of the thalamus form four principal groups or stalks: (a) those of the anterior stalk pass through the frontal part of the internal capsule to the frontal lobe; (b) the fibers of the posterior stalk (optic radiations) arise in the pulvinar and are conveyed through the occipital part of the internal capsule to the occipital lobe; (c) the fibers of the inferior stalk leave the under and medial surfaces of the thalamus, and pass beneath the lentiform nucleus to the temporal lobe and insula; (d) those of the parietal stalk pass from the lateral nucleus of the thalamus to the parietal lobe. Fibers also extend from the thalamus into the corpus striatum—those destined for the caudate nucleus leave the lateral surface, and those for the lentiform nucleus, the inferior surface of the thalamus.
 * The Metathalamus (Fig. 719) comprises the geniculate bodies, which are two in number—a medial and a lateral—on each side.	  14
 * The medial geniculate body (corpus geniculatum mediale; internal geniculate body; postgeniculatum) lies under cover of the pulvinar of the thalamus and on the lateral aspect of the corpora quadrigemina. Oval in shape, with its long axis directed forward and lateralward, it is lighter in color and smaller in size than the lateral. The inferior brachium from the inferior colliculus disappears under cover of it while from its lateral extremity a strand of fibers passes to join the optic tract. Entering it are many acoustic fibers from the lateral lemniscus. The medial geniculate bodies are connected with one another by the commissure of Gudden, which passes through the posterior part of the optic chiasma.	  15
 * The lateral geniculate body (corpus geniculatum laterale; external geniculate body; pregeniculatum) is an oval elevation on the lateral part of the posterior end of the thalamus, and is connected with the superior colliculus by the superior brachium. It is of a dark color, and presents a laminated arrangement consisting of alternate layers of gray and white substance. It receives numerous fibers from the optic tract, while other fibers of this tract pass over or through it into the pulvinar. Its cells are large and pigmented; their axons pass to the visual area in the occipital part of the cerebral cortex.	  16
 * The superior colliculus, the pulvinar, and the lateral geniculate body receive many fibers from the optic tracts, and are therefore intimately connected with sight, constituting what are termed the lower visual centers. Extirpation of the eyes in a newly born animal entails an arrest of the development of these centers, but has no effect on the medial geniculate bodies or on the inferior colliculi. Moreover, the latter are well-developed in the mole, an animal in which the superior colliculi are rudimentary.	  17
 * The Epithalamus comprises the trigonum habenulæ, the pineal body, and the posterior commissure.	  18
 * The trigonum habenulæ is a small depressed triangular area situated in front of the superior colliculus and on the lateral aspect of the posterior part of the tænia thalami. It contains a group of nerve cells termed the ganglion habenulæ. Fibers enter it from the stalk of the pineal body, and others, forming what is termed the habenular commissure, pass across the middle line to the corresponding ganglion of the opposite side. Most of its fibers are, however, directed downward and form a bundle, the fasciculus retroflexus of Meynert, which passes medial to the red nucleus, and, after decussating with the corresponding fasciculus of the opposite side, ends in the interpeduncular ganglion.	  19

after
The {fore-brain [FMA61992:Forebrain]} or {prosencephalon [FMA61992:Forebrain]} consists of: (1) the {diencephalon [FMA62001:Diencephalon]}, corresponding in a large measure to the {third ventricle [FMA78454:Third ventricle]} and the structures which bound it; and (2) the {telencephalon [FMA62000:Telencephalon]}, comprising the largest part of the {brain [FMA50801:Brain]}, viz., the {cerebral hemispheres [FMA61817:Cerebral hemisphere]}; these hemispheres are intimately connected with each other across the middle line, and each contains a large cavity, named the {lateral ventricle [FMA78448:Lateral ventricle]}. The {lateral ventricles [FMA78448:Lateral ventricle]} communicate through the {interventricular foramen [FMA75351:Interventricular foramen]} with the {third ventricle [FMA78454:Third ventricle]}, but are separated from each other by a medial septum, the {septum pellucidum [FMA61842:Septum of telencephalon; FMA61844:Septum pellucidum]}; this contains a slit-like cavity, which does not communicate with the ventricles. The {Diencephalon [FMA62001:Diencephalon]}.—The {diencephalon [FMA62001:Diencephalon]} is connected above and in front with the {cerebral hemispheres [FMA61817:Cerebral hemisphere]}; behind with the {mid-brain [FMA61993:Midbrain]}. Its upper surface is concealed by the {corpus callosum [FMA61946:Genu of corpus callosum; FMA61947:Body of corpus callosum; FMA86464:Corpus callosum]}, and is covered by a fold of {pia mater [FMA9590:Pia mater]}, named the {tela chorioidea of the third ventricle [FMA78463:Tela choroidea of third ventricle]}; inferiorly it reaches to the {base of the brain [FMA77700:Basal forebrain]}. 2   The {diencephalon [FMA62001:Diencephalon]} comprises: (1) the {thalamencephalon [FMA62007:Thalamus]}; (2) the {pars mamillaris hypothalami [FMA62029:Posterior hypothalamic region]}; and (3) the posterior part of the {third ventricle [FMA78454:Third ventricle]}. For descriptive purposes, however, it is more convenient to consider the whole of the {third ventricle [FMA78454:Third ventricle]} and its boundaries together; this necessitates the inclusion, under this heading, of the {pars optica hypothalami [FMA62027:Anterior hypothalamic region]} and the corresponding part of the {third ventricle [FMA78454:Third ventricle]}—structures which properly belong to the {telencephalon [FMA62000:Telencephalon]}. 3   The {Thalamencephalon [FMA62007:Thalamus]}.—The {thalamencephalon [FMA62007:Thalamus]} comprises: (1) the {thalamus [FMA62007:Thalamus]}; (2) the {metathalamus [FMA62023:Metathalamus]} or {corpora geniculata [FMA62023:Metathalamus]}; and (3) the {epithalamus [FMA62009:Epithalamus]}, consisting of the {trigonum habenulæ [FMA74868:Habenular trigone]}, the {pineal body [FMA62033:Pineal body]}, and the {posterior commissure [FMA62072:Posterior commissure]}. The {Thalami [FMA62007:Thalamus]} ({optic thalamus [FMA62007:Thalamus]}) (Figs. 716, 717) are two large ovoid masses, situated one on either side of the {third ventricle [FMA78454:Third ventricle]} and reaching for some distance behind that cavity. Each measures about 4 cm. in length, and presents two extremities, an anterior and a posterior, and four surfaces, superior, inferior, medial, and lateral. 5   The anterior extremity is narrow; it lies close to the middle line and forms the posterior boundary of the {interventricular foramen [FMA75351:Interventricular foramen]}. 6   The posterior extremity is expanded, directed backward and lateralward, and overlaps the {superior colliculus [FMA62403:Superior colliculus]}. Medially it presents an angular prominence, the {pulvinar [FMA62178:Pulvinar]}, which is continued laterally into an oval swelling, the {lateral geniculate body [FMA62209:Lateral geniculate body]}, while beneath the {pulvinar [FMA62178:Pulvinar]}, but separated from it by the {superior brachium [FMA72417:Brachium of superior colliculus]}, is a second oval swelling, the {medial geniculate body [FMA62211:Medial geniculate body]}. 7   The superior surface is free, slightly convex, and covered by a layer of {white substance [FMA83929:White matter of neuraxis]}, termed the {stratum zonale [FMA83905:Stratum zonale of thalamus]}. It is separated laterally from the {caudate nucleus [FMA61833:Caudate nucleus]} by a white band, the {stria terminalis [FMA61974:Stria terminalis]}, and by the {terminal vein [FMA50997:Superior thalamostriate vein]}. It is divided into a medial and a lateral portion by an oblique shallow furrow which runs from behind forward and medialward and corresponds with the lateral margin of the {fornix [FMA61965:Fornix of forebrain]}; the lateral part forms a portion of the floor of the {lateral ventricle [FMA78448:Lateral ventricle]}, and is covered by the epithelial lining of this cavity; the medial part is covered by the {tela chorioidea of the third ventricle [FMA78463:Tela choroidea of third ventricle]}, and is destitute of an epithelial covering. In front, the superior is separated from the medial surface by a salient margin, the {tænia thalami [FMA78461:Tenia of thalamus]}, along which the epithelial lining of the {third ventricle [FMA78454:Third ventricle]} is reflected on to the under surface of the {tela chorioidea [FMA242849:Tela choroidea]}. Behind, it is limited medially by a groove, the {sulcus habenulæ [FMA78466:Habenular sulcus]}, which intervenes between it and a small triangular area, termed the {trigonum habenulæ [FMA74868:Habenular trigone]}. 8   The inferior surface rests upon and is continuous with the upward prolongation of the tegmentum ({subthalamic tegmental region [FMA62010:Subthalamus]}), in front of which it is related to the {substantia innominata of Meynert [FMA61885:Substantia innominata]}. 9   The medial surface constitutes the upper part of the lateral {wall of the third ventricle [FMA242776:Wall of third ventricle]}, and is connected to the corresponding surface of the opposite {thalamus [FMA62007:Thalamus]} by a flattened gray band, the {massa intermedia [FMA74869:Interthalamic adhesion]} (middle or gray commissure). This mass averages about 1 cm. in its antero-posterior diameter: it sometimes consists of two parts and occasionally is absent. It contains {nerve cells [FMA54527:Neuron]} and {nerve fibers [FMA5914:Nerve fiber]}; a few of the latter may cross the middle line, but most of them pass toward the middle line and then curve lateralward on the same side. 10   The lateral surface is in contact with a thick band of {white substance [FMA83929:White matter of neuraxis]} which forms {the occipital part of the internal capsule [FMA61954:Posterior limb of internal capsule]} and separates the {thalamus [FMA62007:Thalamus]} from the {lentiform nucleus [FMA77615:Lentiform nucleus]} of the {corpus striatum [FMA77616:Corpus striatum]}. 11   Structure.—The {thalamus [FMA62007:Thalamus]} consists chiefly of {gray substance [FMA67242:Gray matter of neuraxis]}, but its upper surface is covered by a layer of {white substance [FMA83929:White matter of neuraxis]}, named the {stratum zonale [FMA83905:Stratum zonale of thalamus]}, and its lateral surface by a similar layer termed the {lateral medullary lamina [FMA62469:Lateral medullary lamina of globus pallidus]}. Its {gray substance [FMA67242:Gray matter of neuraxis]} is incompletely subdivided into three parts—anterior, medial, and lateral—by a white layer, the {medial medullary lamina [FMA62079:Internal medullary lamina]}. The anterior part comprises the {anterior tubercle [FMA74867:Anterior tubercle of diencephalon]}, the medial part lies next the lateral {wall of the third ventricle [FMA242776:Wall of third ventricle]} while the lateral and largest part is interposed between the medullary laminæ and includes the {pulvinar [FMA62178:Pulvinar]}. The lateral part is traversed by numerous fibers which radiate from the {thalamus [FMA62007:Thalamus]} into the {internal capsule [FMA61950:Internal capsule]}, and pass through the latter to the {cerebral cortex [FMA61830:Cerebral cortex]}. These three parts are built up of numerous nuclei, the connections of many of which are imperfectly known. 12   Connections.—The {thalamus [FMA62007:Thalamus]} may be regarded as a large ganglionic mass in which the ascending tracts of the tegmentum and a considerable proportion of the fibers of the {optic tract [FMA62046:Optic tract]} end, and from the cells of which numerous fibers (thalamocortical) take origin, and radiate to almost every part of the {cerebral cortex [FMA61830:Cerebral cortex]}. The {lemniscus [FMA83676:Lemniscus of neuraxis]}, together with the other longitudinal strands of the tegmentum, enters its ventral part: the {thalamomammillary fasciculus [FMA83849:Mammillothalamic tract]} ({bundle of Vicq d’Azyr [FMA83849:Mammillothalamic tract]}), from the {corpus mammillare [FMA74877:Mammillary body]}, enters in its {anterior tubercle [FMA74867:Anterior tubercle of diencephalon]}, while many of the fibers of the {optic tract [FMA62046:Optic tract]} terminate in its posterior end. The {thalamus [FMA62007:Thalamus]} also receives numerous fibers (corticothalamic) from the cells of the {cerebral cortex [FMA61830:Cerebral cortex]}. The fibers that arise from the cells of the {thalamus [FMA62007:Thalamus]} form four principal groups or stalks: (a) those of the anterior stalk pass through the {frontal [FMA46757:Frontalis]} part of the {internal capsule [FMA61950:Internal capsule]} to the {frontal lobe [FMA61824:Frontal lobe]}; (b) the fibers of the posterior stalk ({optic radiations [FMA61941:Optic radiation]}) arise in the {pulvinar [FMA62178:Pulvinar]} and are conveyed through {the occipital part of the internal capsule [FMA61954:Posterior limb of internal capsule]} to the {occipital lobe [FMA67325:Occipital lobe]}; (c) the fibers of the inferior stalk leave the under and medial surfaces of the {thalamus [FMA62007:Thalamus]}, and pass beneath the {lentiform nucleus [FMA77615:Lentiform nucleus]} to the {temporal lobe [FMA61825:Temporal lobe]} and {insula [FMA67329:Insula]}; (d) those of the parietal stalk pass from the {lateral nucleus of the thalamus [FMA62174:Lateral nuclear group of thalamus]} to the {parietal lobe [FMA61826:Parietal lobe]}. Fibers also extend from the {thalamus [FMA62007:Thalamus]} into the {corpus striatum [FMA77616:Corpus striatum]}—those destined for the {caudate nucleus [FMA61833:Caudate nucleus]} leave the lateral surface, and those for the {lentiform nucleus [FMA77615:Lentiform nucleus]}, the inferior surface of the {thalamus [FMA62007:Thalamus]}. The {Metathalamus [FMA62023:Metathalamus]} (Fig. 719) comprises the geniculate bodies, which are two in number—a medial and a lateral—on each side. 14   The {medial geniculate body [FMA62211:Medial geniculate body]} ({corpus geniculatum mediale [FMA62211:Medial geniculate body]}; internal geniculate body; postgeniculatum) lies under cover of the {pulvinar [FMA62178:Pulvinar]} of the {thalamus [FMA62007:Thalamus]} and on the lateral aspect of the {corpora quadrigemina [FMA242157:Set of colliculi]}. Oval in shape, with its long {axis [FMA12520:Axis; FMA58907:Axis of lens]} directed forward and lateralward, it is lighter in color and smaller in size than the lateral. The {inferior brachium [FMA71114:Brachium of inferior colliculus]} from the {inferior colliculus [FMA62404:Inferior colliculus]} disappears under cover of it while from its lateral extremity a strand of fibers passes to join the {optic tract [FMA62046:Optic tract]}. Entering it are many acoustic fibers from the {lateral lemniscus [FMA72502:Lateral lemniscus]}. The {medial geniculate bodies [FMA62211:Medial geniculate body]} are connected with one another by the {commissure of Gudden [FMA62052:Ventral supraoptic decussation]}, which passes through the posterior part of the {optic chiasma [FMA62045:Optic chiasm]}. 15   The {lateral geniculate body [FMA62209:Lateral geniculate body]} ({corpus geniculatum laterale [FMA62209:Lateral geniculate body; FMA62214:Dorsal nucleus of lateral geniculate body; FMA62215:Ventral nucleus of lateral geniculate body]}; external geniculate body; pregeniculatum) is an oval elevation on the lateral part of the posterior end of the {thalamus [FMA62007:Thalamus]}, and is connected with the {superior colliculus [FMA62403:Superior colliculus]} by the {superior brachium [FMA72417:Brachium of superior colliculus]}. It is of a dark color, and presents a laminated arrangement consisting of alternate layers of gray and {white substance [FMA83929:White matter of neuraxis]}. It receives numerous fibers from the {optic tract [FMA62046:Optic tract]}, while other fibers of this tract pass over or through it into the {pulvinar [FMA62178:Pulvinar]}. Its cells are large and pigmented; their {axons [FMA67308:Axon]} pass to the visual area in the occipital part of the {cerebral cortex [FMA61830:Cerebral cortex]}. 16   The {superior colliculus [FMA62403:Superior colliculus]}, the {pulvinar [FMA62178:Pulvinar]}, and the {lateral geniculate body [FMA62209:Lateral geniculate body]} receive many fibers from the {optic tracts [FMA62046:Optic tract]}, and are therefore intimately connected with sight, constituting what are termed the lower visual centers. Extirpation of the {eyes [FMA54448:Eye]} in a newly born animal entails an arrest of the development of these centers, but has no effect on the {medial geniculate bodies [FMA62211:Medial geniculate body]} or on the {inferior colliculi [FMA62404:Inferior colliculus]}. Moreover, the latter are well-developed in the mole, an animal in which the {superior colliculi [FMA62403:Superior colliculus]} are rudimentary. 17   The {Epithalamus [FMA62009:Epithalamus]} comprises the {trigonum habenulæ [FMA74868:Habenular trigone]}, the {pineal body [FMA62033:Pineal body]}, and the {posterior commissure [FMA62072:Posterior commissure]}. 18   The {trigonum habenulæ [FMA74868:Habenular trigone]} is a small depressed triangular area situated in front of the {superior colliculus [FMA62403:Superior colliculus]} and on the lateral aspect of the posterior part of the {tænia thalami [FMA78461:Tenia of thalamus]}. It contains a group of {nerve cells [FMA54527:Neuron]} termed the {ganglion [FMA5884:Ganglion]} habenulæ. Fibers enter it from the stalk of the {pineal body [FMA62033:Pineal body]}, and others, forming what is termed the {habenular commissure [FMA62048:Habenular commissure]}, pass across the middle line to the corresponding {ganglion [FMA5884:Ganglion]} of the opposite side. Most of its fibers are, however, directed downward and form a bundle, the {fasciculus retroflexus of Meynert [FMA72400:Habenulo-interpeduncular tract]}, which passes medial to the {red nucleus [FMA62407:Red nucleus]}, and, after decussating with the corresponding fasciculus of the opposite side, ends in the {interpeduncular ganglion [FMA72439:Interpeduncular nucleus]}. 19