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Questions and Answers
The forebrain develops from a single neural tube, with the lamina terminalis forming its cranial end.
The forebrain develops from a single neural tube, with the lamina terminalis forming its cranial end.
True (A)
The cerebral vesicles form from the expansion of the diencephalon's side walls.
The cerebral vesicles form from the expansion of the diencephalon's side walls.
False (B)
The third ventricle communicates with the lateral ventricles via the cerebral aqueduct.
The third ventricle communicates with the lateral ventricles via the cerebral aqueduct.
False (B)
The roof and floor of the diencephalon converge anteriorly, where they meet the midbrain.
The roof and floor of the diencephalon converge anteriorly, where they meet the midbrain.
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The lamina terminalis extends from the genu of the corpus callosum to the optic chiasma.
The lamina terminalis extends from the genu of the corpus callosum to the optic chiasma.
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The anterior commissure is located in the posterior wall of the third ventricle.
The anterior commissure is located in the posterior wall of the third ventricle.
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The aqueduct of Sylvius connects the third ventricle to the lateral ventricle.
The aqueduct of Sylvius connects the third ventricle to the lateral ventricle.
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The diencephalon is located caudal to the midbrain.
The diencephalon is located caudal to the midbrain.
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The anterior commissure connects the two piriform areas of the cortex.
The anterior commissure connects the two piriform areas of the cortex.
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The optic chiasma is located within the roof of the diencephalon.
The optic chiasma is located within the roof of the diencephalon.
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The anterior pole of the thalamus, covered in ependyma, is situated at the interventricular foramen.
The anterior pole of the thalamus, covered in ependyma, is situated at the interventricular foramen.
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The lateral surface of the thalamus is bevelled by the external capsule, whose descending fibres lie in contact.
The lateral surface of the thalamus is bevelled by the external capsule, whose descending fibres lie in contact.
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The inferior surface of the thalamus is broader than the superior surface.
The inferior surface of the thalamus is broader than the superior surface.
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The medial cell groups of the thalamus receive fibres from the hypothalamus and corpus striatum and have reciprocal connections with the frontal lobes, potentially relating to emotional responses and memory.
The medial cell groups of the thalamus receive fibres from the hypothalamus and corpus striatum and have reciprocal connections with the frontal lobes, potentially relating to emotional responses and memory.
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The anterior thalamic nucleus projects to the cingulate gyrus and receives fibres from the hypothalamus via the corticothalamic tract.
The anterior thalamic nucleus projects to the cingulate gyrus and receives fibres from the hypothalamus via the corticothalamic tract.
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Medial and lateral geniculate bodies are specialized parts of the thalamus associated with vision and hearing respectively.
Medial and lateral geniculate bodies are specialized parts of the thalamus associated with vision and hearing respectively.
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The choroid fissure is a C-shaped slit in the medial wall of the cerebral hemisphere extending to the uncus of the parietal lobe.
The choroid fissure is a C-shaped slit in the medial wall of the cerebral hemisphere extending to the uncus of the parietal lobe.
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The tela choroidea is formed by three layers of pia mater lying in contact over the dorsal surface of the diencephalon.
The tela choroidea is formed by three layers of pia mater lying in contact over the dorsal surface of the diencephalon.
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The choroid plexuses of the third ventricle are larger than those of the lateral ventricle and are discontinuous with them.
The choroid plexuses of the third ventricle are larger than those of the lateral ventricle and are discontinuous with them.
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Striate arteries and thalamic veins pass through the anterior perforated substance in the floor of the third ventricle.
Striate arteries and thalamic veins pass through the anterior perforated substance in the floor of the third ventricle.
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The thalamus is part of the wall of the diencephalon, which is the part of the forebrain that does not expand into the cerebral hemispheres.
The thalamus is part of the wall of the diencephalon, which is the part of the forebrain that does not expand into the cerebral hemispheres.
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The pineal cells secrete somatostatin, which in animals and probably in man has an antigonadotrophic action.
The pineal cells secrete somatostatin, which in animals and probably in man has an antigonadotrophic action.
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The interthalamic adhesion joins the medial walls of the two thalami in approximately two-thirds of cases.
The interthalamic adhesion joins the medial walls of the two thalami in approximately two-thirds of cases.
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The posterior commissure connects the superior colliculi above the entrance to the cerebral aqueduct.
The posterior commissure connects the superior colliculi above the entrance to the cerebral aqueduct.
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The anterior commissure is thought to be unrelated to the olfactory system, unlike the habenular commissure.
The anterior commissure is thought to be unrelated to the olfactory system, unlike the habenular commissure.
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The pial roof of the third ventricle extends forward to the anterior pole of the thalamus, sweeps across to the anterior column of the fornix, and then continues as the upper layer of the tela choroidea, lined with arachnoid mater.
The pial roof of the third ventricle extends forward to the anterior pole of the thalamus, sweeps across to the anterior column of the fornix, and then continues as the upper layer of the tela choroidea, lined with arachnoid mater.
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The pineal body is located below the splenium and lies above the inferior colliculi between the posterior parts of the thalami.
The pineal body is located below the splenium and lies above the inferior colliculi between the posterior parts of the thalami.
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The pineal recess distinguishes itself from the larger suprapineal recess because it is located between the pineal body and the posterior commissure.
The pineal recess distinguishes itself from the larger suprapineal recess because it is located between the pineal body and the posterior commissure.
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The medial geniculate body receives fibers from the vestibulocochlear nerves and relays them through the sublentiform part of the internal capsule to the auditory cortex.
The medial geniculate body receives fibers from the vestibulocochlear nerves and relays them through the sublentiform part of the internal capsule to the auditory cortex.
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Brain sand, or corpora amylacea, is a type of particle that calcifies in the choroid plexuses, and the degree of this calcification is commonly significant enough to be visible on skull radiographs after the age of 40 years.
Brain sand, or corpora amylacea, is a type of particle that calcifies in the choroid plexuses, and the degree of this calcification is commonly significant enough to be visible on skull radiographs after the age of 40 years.
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The anterior wall and floor of the third ventricle are not visible in a median sagittal section.
The anterior wall and floor of the third ventricle are not visible in a median sagittal section.
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The cavity of the septum pellucidum connects directly with the ventricular system, often referred to as the 'fifth ventricle.'
The cavity of the septum pellucidum connects directly with the ventricular system, often referred to as the 'fifth ventricle.'
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The interthalamic adhesion is a true commissure, facilitating an interchange of fibers between the two sides of the thalamus.
The interthalamic adhesion is a true commissure, facilitating an interchange of fibers between the two sides of the thalamus.
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The hypothalamic groove is situated above the thalamus, curving down from the interventricular foramen.
The hypothalamic groove is situated above the thalamus, curving down from the interventricular foramen.
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The subthalamic nucleus belongs functionally to the cerebellar nuclei.
The subthalamic nucleus belongs functionally to the cerebellar nuclei.
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Axons from the supraoptic and paraventricular nuclei within the hypothalamus project to the anterior lobe of the pituitary gland for hormone control.
Axons from the supraoptic and paraventricular nuclei within the hypothalamus project to the anterior lobe of the pituitary gland for hormone control.
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The posterior perforated substance is located between the infundibulum and the mamillary bodies.
The posterior perforated substance is located between the infundibulum and the mamillary bodies.
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The median eminence, part of the tuber cinereum, possesses a blood/brain barrier similar to most other brain regions.
The median eminence, part of the tuber cinereum, possesses a blood/brain barrier similar to most other brain regions.
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The anterior commissure connects the two piriform cortices and is a part of the neopallium.
The anterior commissure connects the two piriform cortices and is a part of the neopallium.
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The tela choroidea is a single fold of arachnoid mater roofing the third ventricle.
The tela choroidea is a single fold of arachnoid mater roofing the third ventricle.
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Flashcards
Diencephalon
Diencephalon
Region of the forebrain located above the midbrain, contains the third ventricle.
Third Ventricle
Third Ventricle
Cavity within the diencephalon that connects the lateral ventricles to the midbrain.
Lamina Terminalis
Lamina Terminalis
Thin plate of grey matter forming the anterior wall of the diencephalon.
Aqueduct of Sylvius
Aqueduct of Sylvius
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Interventricular Foramina
Interventricular Foramina
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Cerebral Hemispheres
Cerebral Hemispheres
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Hypothalamic Sulcus
Hypothalamic Sulcus
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Anterior Commissure
Anterior Commissure
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Foramen
Foramen
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Choroid Plexus
Choroid Plexus
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Septum Pellucidum
Septum Pellucidum
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Thalamus
Thalamus
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Hypothalamus
Hypothalamus
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Infundibulum
Infundibulum
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Tuber Cinereum
Tuber Cinereum
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Mamillary Bodies
Mamillary Bodies
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Ependyma
Ependyma
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Interthalamic Adhesion
Interthalamic Adhesion
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Habenular Commissure
Habenular Commissure
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Pia Mater
Pia Mater
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Pineal Body
Pineal Body
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Melatonin
Melatonin
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Neothalamus
Neothalamus
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Medial Geniculate Body
Medial Geniculate Body
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Superior Surface of Thalamus
Superior Surface of Thalamus
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Internal Capsule
Internal Capsule
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Lateral Geniculate Body
Lateral Geniculate Body
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Ventroposterior Nucleus
Ventroposterior Nucleus
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Tela Choroidea
Tela Choroidea
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Study Notes
Diencephalon and Third Ventricle
- Forebrain is cranial to midbrain, formed from a single neural tube
- Lamina terminalis, a thin plate of grey matter, forms the cranial end
- Cerebral hemispheres develop from bulges (ventricles) caudal to lamina terminalis
- Diencephalon remains relatively unexpanded, enclosed by lamina terminalis
- Third ventricle is the cavity within the diencephalon, connected to lateral ventricles via interventricular foramina
- Diencephalon has side walls, floor, and roof; roof and floor converge posteriorly to meet the midbrain
- Third ventricle continues through midbrain as aqueduct, leading to fourth ventricle
Third Ventricle Structure
- Anterior wall: lamina terminalis, extends between hemispheres from corpus callosum rostrum to optic chiasma, contains anterior commissure
- Floor: extends from optic chiasma, tuber cinereum, infundibulum, mamillary bodies to posterior perforated substance, joins cerebral peduncles tegmentum
- Septum pellucidum: thin partition connecting corpus callosum and fornix; part of medial hemisphere surface; function unknown, separate from ventricular system
- Third ventricle is slit-like, largely occupied by thalamus (rounded grey matter bulge)
- Interthalamic adhesion: often joins thalami (60% of brains) - not a commissure
- Hypothalamic groove: curves down from interventricular foramen towards midbrain aqueduct
- Hypothalamus: region below hypothalamic groove including floor; subthalamus (caudal part) includes subthalamic nucleus
- Infundibulum (hollow): projects downward from optic chiasma, becomes pituitary stalk
- Tuber cinereum: (part of floor) between infundibulum & mamillary bodies
- Median eminence: base of tuber cinereum, neurosecretory cells controlling anterior pituitary, lacks blood-brain barrier
- Mamillary bodies and posterior perforated substance: mark external floor, don't directly impact ventricle
- Supraoptic and infundibular recesses: tiny angles surrounding structures
Third Ventricle Lining and Contents
- Lined by ependyma, continuous with lateral and fourth ventricles
- Choroid plexus(small): invaginates the roof, hang down in slender fringes
- Medullary stria of thalamus: thin band of white matter attached to thalamus, connects to piriform area, habenular commissure
- Pial roof: pia mater lines third ventricle, attached to medullary striae, extends from anterior thalamus pole to anterior fornix
- Pineal body(soft cone): Projects behind thalamus, contains corpora amylacea(calcify in adulthood)
- Pineal recess: Hollow in pineal stalk between habenular and posterior commissures
- Tela choroidea: double fold of pia mater, roofs over interventricular foramen, folds back between foramina and the fornix
- Internal cerebral veins: run back on pia mater of inferior layer of tela choroidea
- Choroid fissure: C-shaped slit containing choroid plexus
Thalamus Structure and Function
- Thalamus wedge-shaped mass of grey matter; medial walls lie parallel
- Medial surface covered by third ventricle ependyma
- Bulges into pulvinar and lateral geniculate body
- Lateral geniculate and medial geniculate bodies: relays visual and auditory impulses respectively
- Superior surface convex and triangular, tapers to anterior pole covered by pia mater
- Lateral surface bevelled by internal capsule (ascending and descending fibers)
- Inferior surface narrower than superior surface, joins hypothalamus to posterior perforated substance, numerous striate arteries and thalamic veins pass here
- Thalamic nuclei: numerous cell groups (lateral, medial, anterior).
- Ventroposterior nuclei, receive information from sensory pathways and relays it to the cerebral cortex; contribute to motor control
- Other nuclei have connections with hypothalamus and corpus striatum and frontal lobes (emotional responses & memory); mamillothalamic tract
- Development: Thalamus part of diencephalon; neothalamus adds fibers to sensory cortex, and becomes integrated into hemisphere pathways
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Description
This quiz covers the anatomy and structure of the diencephalon and the third ventricle. It explores the features such as the lamina terminalis, cerebral hemispheres, and the connections between ventricular systems. Perfect for students of neuroanatomy or those studying the brain's structural organization.
