What are the two tracts that belong to the epicritic sensibility pathway?
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Fasciculus gracilis and fasciculus cuneatus.
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What are the two tracts that belong to the epicritic sensibility pathway?
Fasciculus gracilis and fasciculus cuneatus.
What type of fibers does the vestibulocochlear nerve (VIIIth cranial nerve) contain?
Sensory fibers.
What type of neurons compose the fasciculus gracilis and fasciculus cuneatus?
Axons of the pseudounipolar neurons of the spinal ganglion.
Into how many parts is the vestibulocochlear nerve divided?
Two parts: n. vestibularis and n. cochlearis.
Where is the grey matter of the cerebellum mainly located?
At the surface, forming cortex cerebelli.
Where do the fibres of fasciculus gracilis and fasciculus cuneatus synapse with the 2nd neurons?
At nucleus gracilis and nucleus cuneatus.
How many sensory nuclei does the n. vestibularis have?
Four sensory nuclei: nuclei vestibulares.
What is the function of the nucleus dentatus in the cerebellum?
It takes part in coordination of the movements of the limbs.
What are the two groups of fibres formed by the axons of nucleus gracilis and nucleus cuneatus?
Fibrae arcuatae externae and fibrae arcuatae internae.
How many sensory nuclei does the n. cochlearis have?
Two sensory nuclei: nucleus cochlearis anterior and posterior.
Which cerebellar nucleus is responsible for the coordination of trunk movements?
Nucleus emboliformis and nucleus globosus.
Where do fibrae arcuatae externae run to?
To the cerebellum through pedunculi cerebellares inferiores.
What types of fibers does the glossopharyngeal nerve (IXth cranial nerve) contain?
Motor, sensory, and parasympathetic fibers.
What is the outermost covering of the spinal cord?
The spinal dura mater.
What is the role of the nucleus fastigii in the cerebellum?
It provides balance of the body.
What is the pathway of fibrae arcuatae internae?
They are crossed (decussatio lemnisci medialis) and ascend as lemniscus medialis.
How many nuclei does the glossopharyngeal nerve have and what are they?
Three nuclei: nucleus ambiguus (motor), nucleus tractus solitarii (sensory), and nucleus salivatorius inferior (parasympathetic).
What separates the spinal dura mater from the periosteal lining of the vertebral canal?
The epidural space (spatium epidurale).
What characteristic appearance does the white matter of vermis have in sagittal section?
Arbor vitae.
Where does lemniscus medialis travel to synapse with the 3rd neurons?
To the thalamus (diencephalon).
What types of fibers does the vagus nerve (Xth cranial nerve) contain?
Motor, sensory, and parasympathetic fibers.
What fills the epidural space?
Fatty tissue, lymphatic vessels, and venous plexus.
What sensation does tractus spinothalamicus lateralis transmit?
Pain and temperature sensation.
What tracts are contained in the pedunculi cerebellares inferiores?
Tractus spinocerebellaris posterior, fibrae arcuatae externae, tractus olivocerebellaris, and tractus vestibulocerebellaris.
How many nuclei does the vagus nerve have and what are they?
Three nuclei: nucleus ambiguus (motor), nucleus tractus solitarii (sensory), and nucleus dorsalis (posterior) n. vagi (parasympathetic).
What does the spinal dura mater continue as caudally?
The external part of the terminal filum.
What sensation does tractus spinothalamicus anterior transmit?
Touch sensation.
Which tract is contained in the pedunculi cerebellares medii?
Tractus pontocerebellaris.
What types of fibers does the accessory nerve (XIth cranial nerve) contain?
Motor fibers.
Describe the spinal arachnoid mater.
It is a delicate trabeculated layer.
Where do both spinothalamic tracts run up to synapse?
At the thalamus (diencephalon).
What tracts are contained in the pedunculi cerebellares superiores?
Tractus spinocerebellaris anterior and tractus cerebellorubralis.
How many nuclei does the accessory nerve have and what are they?
Two nuclei: nucleus ambiguus (motor) and nucleus n. accessorii (motor).
What is the subdural space (spatium subdurale)?
The space between the spinal dura mater and the spinal arachnoid mater, which becomes a true cavity only under pathological conditions.
Where does tractus spinocerebellaris posterior reach?
The cerebellum via pedunculus cerebellaris inferior.
What is the function of the tractus cerebellorubralis?
It is part of the pathway for voluntary and involuntary coordination of movements.
What are the two parts of the XIth nerve?
Radix cranialis and radix spinalis.
What is the pathway of tractus spinocerebellaris anterior?
It passes through pons and mesencephalon and then reaches the cerebellum via pedunculus cerebellaris superior.
What does the spinal arachnoid mater continue as upward and downward?
Upward it continues into a similar covering for the brain, and downward it fuses with the terminal filum.
What is the mesencephalon considered part of?
The brainstem.
What type of fibers does the hypoglossal nerve (XIIth cranial nerve) contain?
Motor fibers.
What is the fourth ventricle and where is it located?
The fourth ventricle is the cavity of the rhombencephalon, tent-shaped and formed by the roof (tegmen ventriculi quarti) and the base (fossa rhomboidea).
What is tractus corticospinalis formed by?
Axons of pyramidal cells of the cortex.
What lies directly on the spinal cord?
The spinal pia mater.
What are the two main parts of the mesencephalon?
Lamina tecti (posterior part) and pedunculi cerebri (anterior part).
How many nuclei does the hypoglossal nerve have and what is it called?
One nucleus: nucleus n. hypoglossi.
Where is the VIth cranial nerve (nervus abducens) located?
Between pyramis and pons.
What forms the upper part of the roof of the fourth ventricle?
The upper part of the roof contains velum medullare superius, a thin layer of white matter stretched between pedunculi cerebellares superiores.
What is the function of tractus corticospinalis?
Voluntary control of skeletal muscles for the trunk and limbs.
What is the subarachnoid space (spatium subarachnoideum) filled with?
Cerebrospinal fluid (liquor cerebrospinalis).
What does the aqueductus mesencephali connect?
The fourth ventricle with the third ventricle.
Which cranial nerve is sometimes described separately as the XIIIth cranial nerve?
Nervus intermedius, part of the VIIth cranial nerve (nervus facialis).
Where are the motor nuclei arranged in the rhomboid fossa?
In the middle part of the rhomboid fossa close to sulcus medianus.
What forms the lower part of the roof of the fourth ventricle?
The lower part of the roof consists of velum medullare inferius, a thin layer of white matter stretched between pedunculi cerebellares inferiores.
What is tractus corticonuclearis concerned with?
Voluntary control of skeletal muscles for the head and neck.
Why is the lumbar region an ideal place to access the subarachnoid space?
Because the spinal cord terminates at the level of the 1st to the 2nd lumbar vertebrae.
What are the subcortical visual centers in the lamina tecti?
Colliculi superiores.
Where do the VIIth and VIIIth cranial nerves appear in relation to the VIth nerve?
Laterally to the VIth nerve between oliva and pedunculus cerebellaris medius.
What is the function of the plexus choroideus in the fourth ventricle?
The plexus choroideus produces cerebrospinal fluid (liquor cerebrospinalis).
What are the general functions of the cerebellum?
Coordination of movements and balance, providing muscle tone, and coordinating muscular functions in movements and posture.
What is the purpose of a lumbar puncture?
To obtain a sample of cerebrospinal fluid for examination or to inject antibiotics or anesthetics.
What is tractus vestibulospinalis formed by?
Axons of nuclei vestibulares.
What are the two roots of the Vth cranial nerve (nervus trigeminus)?
Radix sensoria (thick) and radix motoria (thin).
What are the subcortical centers of hearing in the lamina tecti?
Colliculi inferiores.
What connects the fourth ventricle to the third ventricle?
The fourth ventricle is connected to the third ventricle by the aquaeductus mesencephali (cerebri).
Where is the cerebellum located?
Behind the pons and medulla oblongata in fossa cranii posterior.
From what does the brain (encephalon) develop?
The upper part of the neural tube in the fetus.
What is the role of tractus vestibulocerebellaris?
Takes part in balance pathway.
What forms the upper part of fossa rhomboidea?
The dorsal surface of the pons.
Where does the brachium colliculi superioris extend to and what does it carry?
It extends to corpus geniculatum laterale and carries fibers of the visual pathway.
What are the three apertures of the fourth ventricle?
The fourth ventricle has three apertures: apertura mediana and two aperturae laterales.
What are the main structural components of the cerebellum?
Two hemispheres and a narrow connecting part called vermis.
What are the three initial vesicles of the brain during development?
Prosencephalon, mesencephalon, and rhombencephalon.
What is tractus olivospinalis formed by?
Axons of nuclei olivares.
What is stretched between the pedunculi cerebellares superiores?
Velum medullare superius.
Where does the brachium colliculi inferioris pass to and what does it carry?
It passes to corpus geniculatum mediale and carries fibers of the auditory pathway.
What forms the rhomboid fossa?
The rhomboid fossa is formed by the dorsal surfaces of the pons and medulla oblongata.
What separates the folia on the surface of the cerebellum?
Cerebellar fissures.
What are the five vesicles formed at later stages of brain development?
Telencephalon, diencephalon, mesencephalon, metencephalon, and myelencephalon.
What is the role of tractus olivocerebellaris?
Takes part in balance regulation.
What are the two parts of the pons on a horizontal section?
The basilar part (anteriorly) and the tegmentum of pons (posteriorly).
Which cranial nerve appears below the colliculi inferiores?
Nervus trochlearis (trochlear nerve, IVth cranial nerve).
What divides the rhomboid fossa into two symmetrical halves?
The rhomboid fossa is divided by sulcus medianus into two symmetrical halves.
What parts of the brain are formed from the telencephalon?
The telencephalon forms the telencephalon and the lateral ventricles.
How is the cerebellum connected to other parts of the brain?
By three pairs of peduncles: pedunculi cerebellares superiores (to mesencephalon), pedunculi cerebellares medii (to pons), and pedunculi cerebellares inferiores (to medulla oblongata).
Where does the pons lie in the cranium?
On the clivus.
What is the corpus trapezoideum?
A formation of white matter part of the auditory pathway, located between the basilar part and the tegmentum of pons.
Where do the pedunculi cerebri emerge from and where do they enter?
They emerge from pons upward and laterally and enter the lower parts of the cerebral hemispheres.
What is the function of striae medullares ventriculi quarti in the rhomboid fossa?
Striae medullares ventriculi quarti are myelinated nerve fibers that divide the rhomboid fossa into upper and lower parts.
What parts of the brain are formed from the diencephalon?
Thalamus, subthalamus, epithalamus, metathalamus, and hypothalamus.
What are the nuclei pontis?
The 2nd neurons of the pathway for the voluntary coordination of movements.
What is located at the bottom of the interpeduncular fossa?
A layer of gray matter with openings called substantia perforata posterior.
What is the colliculus facialis and where is it located?
The colliculus facialis is an elongate swelling located above the striae medullares in the rhomboid fossa.
What parts of the brain are formed from the mesencephalon?
Lamina tecti and pedunculi cerebri.
What are the fibrae pontis transversae?
Tract fibers that synapse in the pontine nuclei (tractus corticopontinus and tractus pontocerebellaris).
What parts of the brain are formed from the metencephalon?
Pons and cerebellum.
What are the trigonum n. vagi and trigonum n. hypoglossi?
The trigonum n. vagi and trigonum n. hypoglossi are areas located below the striae medullares in the rhomboid fossa.
Which cranial nerve nuclei are located in the tegmentum of pons?
Nuclei of the cranial nerves Vth – VIIIth.
What parts of the brain are formed from the myelencephalon?
Medulla oblongata.
What is the area vestibularis and where is it located?
The area vestibularis is an elevation at the lateral angle of the rhomboid fossa, crossed by striae medullares ventriculi quarti.
What is the function of the nuclei corporis trapezoidei?
They are part of the auditory pathway.
Which cranial nerve nuclei are projected in the rhomboid fossa?
The nuclei of the cranial nerves, including the trigeminal nerve (V), abducent nerve (VI), and facial nerve (VII), are projected in the rhomboid fossa.
What structures together form the brainstem?
Medulla oblongata, pons, and mesencephalon.
What is the formatio reticularis?
A network of neurons located in the tegmentum of pons.
What are the four nuclei of the trigeminal nerve (V)?
The four nuclei of the trigeminal nerve are: nucleus motorius n. trigemini (motor), nucleus principalis n. trigemini (sensory, touch), nucleus mesencephalicus n. trigemini (sensory, epicritic sensibility), and nucleus spinalis n. trigemini (sensory, pain and temperature).
What are the descending tracts in the white matter of the basilar part of the pons?
Tractus corticospinalis, tractus corticonuclearis, tractus corticopontinus, and tractus pontocerebellaris.
What is the nucleus of the abducent nerve (VI)?
The abducent nerve contains motor fibers and has one nucleus: nucleus n. abducentis.
What is the function of the tractus corticospinalis?
It belongs to the pyramidal system.
What is the nucleus of the facial nerve (VII)?
The facial nerve contains motor fibers and has one nucleus: nucleus n. facialis.
What is the function of the tractus corticonuclearis?
It belongs to the pyramidal system and has synapses with the motor nuclei of the cranial nerves (Vth, VIth, VIIth).
What are the two nuclei of the intermedial nerve (XIII)?
The intermedial nerve contains sensory and parasympathetic fibers and has two nuclei: nucleus salivatorius superior (parasympathetic) and nucleus tractus solitarii (sensory).
What is the pathway for the voluntary coordination of movements in the pons?
Tractus corticopontinus and tractus pontocerebellaris.
Where are the 1st neurons of the pathway for coordination of movements located?
In the frontal, parietal, occipital, and temporal regions of cortex cerebri.
What are the ascending tracts in the white matter of the tegmentum of pons?
Lemniscus medialis, lemniscus spinalis, lemniscus trigeminalis, tractus spinocerebellaris anterior, lemniscus lateralis, and corpus trapezoideum.
What are the descending tracts in the white matter of the tegmentum of pons?
Tractus tectospinalis and tractus rubrospinalis.
