Mesencephalon (Midbrain)
Mesencephalon (Midbrain) – External & Internal structures Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 Mesencephalon – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 Which midbrain structure is involved in reflex control of balance and posture? A) Reticulospinal Tract B) Vestibulospinal Tract C) Rubrospinal Tract D) Corticospinal Tract The vestibulospinal tract originates in the brainstem, including the midbrain, to maintain balance and posture. 2 / 10 What part of the midbrain contains the corticospinal and corticopontine tracts? A) Cerebral Peduncles B) Red Nucleus C) Tegmentum D) Tectum The cerebral peduncles house the corticospinal and corticopontine tracts, which are involved in motor signal transmission. 3 / 10 Which midbrain structure is associated with the auditory pathway? A) Inferior Colliculus B) Lateral Lemniscus C) Medial Lemniscus D) Superior Colliculus The inferior colliculus processes auditory input and relays it to the medial geniculate body of the thalamus. 4 / 10 Which cranial nerve exits dorsally from the midbrain? A) Oculomotor Nerve B) Trochlear Nerve C) Trigeminal Nerve D) Abducens Nerve The trochlear nerve (CN IV) is the only cranial nerve to exit from the dorsal surface of the brainstem. 5 / 10 What is the function of the tectospinal tract originating in the superior colliculus? A) Voluntary Movement B) Auditory Reflex C) Visual Reflex Movement D) Pain Modulation The tectospinal tract coordinates head and neck movements in response to visual stimuli. 6 / 10 Which cranial nerve emerges between the cerebral peduncles of the midbrain? A) Abducens Nerve B) Trigeminal Nerve C) Trochlear Nerve D) Oculomotor Nerve The oculomotor nerve (CN III) emerges between the cerebral peduncles on the anterior surface of the midbrain. 7 / 10 The superior colliculus is connected to the primary visual cortex via which structure? A) Lateral Lemniscus B) Brachium of Superior Colliculus C) Medial Lemniscus D) Tectospinal Tract The brachium of the superior colliculus transmits visual signals to the primary visual cortex through the lateral geniculate body. 8 / 10 Which midbrain pathway connects the cochlear nuclei to the inferior colliculus? A) Spinothalamic Tract B) Lateral Lemniscus C) Trigeminal Lemniscus D) Medial Lemniscus The lateral lemniscus is part of the auditory pathway, transmitting signals from the cochlear nuclei to the inferior colliculus. 9 / 10 What structure in the midbrain relays motor information from the cerebellum to the thalamus? A) Tectum B) Lateral Lemniscus C) Substantia Nigra D) Red Nucleus The red nucleus integrates motor information from the cerebellum and relays it to the thalamus for coordination. 10 / 10 What is the tectum of the midbrain composed of? A) Tegmentum B) Cerebral Peduncles C) Superior and Inferior Colliculi D) Substantia Nigra The tectum of the midbrain includes the superior and inferior colliculi, which are involved in visual and auditory reflexes, respectively. Your score is The average score is 0% Description Topography of the Mesencephalon Lies above the Pons, Below Diencephalon, In front of the Cerebellum Anterior Surface Posterior Surface Anterior Surface of the Mesencephalon Cerebral Peduncles (Pedunculus Cerebri) Interpeduncular Fossa (Fossa Interpeduncularis) Posterior Perforated Substance (Substantia Perforata Posterior) Oculomotor Sulcus of Mesencephalon (Sulcus Nervi Oculomotorii) 3rd Cranial Nerve (Oculomotor nerve) Posterior View of the Mesencephalon Cerebral Peduncles (Pedunculus Cerebri) Tectal Plate (Lamina Tecti) Superior Colliculus (Colliculi Superior) Visual Pathway: Receptors of Optic Nerve (CNII) Optic Chiasm Lateral Geniculate Body (Metathalamus) Primary Visual Cortex Brachium of the Superior Colliculi (Brachium Colliculi Superior) Inferior Colliculus (Colliculi Inferior) Auditory Pathway: Cochlear Nerve Cochlear Nuclei Lateral Lemniscus Inferior Colliculi Brachium of the Inferior Colliculi (Brachium Colliculi Inferior) Primary Auditory Cortex (Superior Temporal Gyrus) Lateral Sulcus of Mesencephalon (Sulcus Lateralis Mesencephali) Trigone of Lateral Lemniscus (Trigonum Lemnisci Lateralis) Trochlear Nerve (CN IV) Internal Surface of the Mesencephalon Tectum of Midbrain Tegmentum of Midbrain Cerebral Peduncles Gray Matter of Mesencephalon Red Nucleus (Nucleus Ruber) Corticopontine Tract Pontocerebellar Tract (Transverse Pontine Fibers) Cerebellorubral Tract Rubrospinal Tract Substantia Nigra Substantia Nigra pars Reticulata Substantia Nigra pars Compacta Part of Basal Ganglia (Putamen, Globus Pallidus, Caudate, Thalamus, Subthalamus, Striatum, Lentiform Nucleus) Helps Start Movement, Stop Movement, Modulate Movement Disease here causes Parkinson’s Disease and TRAP symptoms (Tremor, Rigidity, Akinesia, Postural Instability) Superior Colliculi Level: Nucleus of Oculomotor Nerve (Nuclei Nervi Oculomotorii) Posterior Accessory Nucleus of Oculomotor Nerve (Nucleus Accessorii Nervi Oculomotorii) Inferior Colliculi Level: Nucleus of Trochlear Nerve (Nuclei Nervi Trochlearis) Mesencephalic Nucleus of Trigeminal Nerve (Nucleus Mesencephalicus Nervi Trigemini) Periaqueductal Grey Substance (Substantia Grisea Centralis) Reticular Formation (Formatio Reticularis) White Matter of Mesencephalon Ascending Tracts Medial Lemniscus (Lemniscus Medialis) Gracile Fascicle (Fasciculus Gracilis) to Gracile Nucleus Cuneate Fascicle (Fasciculus Cuneatus) to Cuneate Nucleus Medial Lemniscus is formed through Internal Arcuate Fibers (Fibrae Arcuatae Internae) Epicritic Sensibility (Proprioception and Mechanoreceptors) Spinal Lemniscus (Lemniscus Spinalis) Anterior Spinothalamic Tract (Tractus Spinothalamicus Anterior) Lateral Spinothalamic Tract (Tractus Spinothalamicus Lateralis) Trigeminal Lemniscus (Lemniscus Trigeminalis) Anterior Spinocerebellar Tract (Tractus Spinocerebellaris Anterior) Lateral Lemniscus (Lemniscus Lateralis) from Cochlear Nerve Descending Tracts Vestibulospinal Tract (Tractus Vestibulospinalis) Rubrospinal Tract (Tractus Rubrospinalis) Tectospinal Tract (Tractus Tectospinalis) Posterior Tegmental Decussation (Decussatio Tegmentalis Posterior) Reticulospinal Tract (Tractus Reticulospinalis) Anterior Tegmental Decussation (Decussatio Tegmentalis Anterior) Medial Longitudinal Fasciculus (Fasciculus Longitudinalis Medialis) In the Cerebral Peduncles Corticospinal Tract (Tractus Corticospinalis) Corticonuclear Tract (Corticobulbar Tract) Corticopontine Tract (Tractus Corticopontineus) Frontopontine Tract Parietopontine Tract Temporopontine Tract Occipitopontine Tract Transcript Introduction 0:03 What’s up. Meditay here. Let’s continue the anatomy of the Central Nervous System. 0:08 In this segment, we’ll cover the complete anatomy of the Midbrain, also known as the mesencephalon 0:13 So remember, the central nervous system consists of two parts: 0:16 the encephalon and the spinal cord. The encephalon is then further divided into specific parts. 0:22 We have the brainstem, which consists of the Medulla, Pons, and the midbrain or the 0:26 mesencephalon. We have the cerebellum back here, then the Diencephalon and the telencephalon. 0:31 Our focus in this video is
4th Ventricle and the Rhomboid fossa
4th Ventricle and Rhomboid Fossa Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 4th Ventricle and Rhomboid Fossa – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 Which structure demarcates the transition to the central canal? A) Vestibular area B) Median sulcus C) Foramen of Magendie D) Obex The obex marks the transition from the 4th ventricle to the central canal. 2 / 10 Which cranial nerve nucleus lies beneath the hypoglossal trigone? A) Vestibular nucleus B) Hypoglossal nucleus C) Vagal nucleus D) Facial nucleus The hypoglossal nucleus lies beneath the hypoglossal trigone and innervates tongue muscles. 3 / 10 The striae medullares mark the boundary between which structures? A) Inferior cerebellar peduncles B) Vestibular nuclei C) Pons and medulla D) Superior cerebellar peduncles The striae medullares separate the pons and medulla on the floor of the 4th ventricle. 4 / 10 The facial colliculus is formed by fibers of which cranial nerve? A) Vagus nerve (CN X) B) Facial nerve (CN VII) C) Glossopharyngeal nerve (CN IX) D) Trigeminal nerve (CN V) The facial colliculus is formed by fibers of the facial nerve (CN VII) looping around the abducens nucleus (CN VI). 5 / 10 Which cranial nerve nucleus is associated with facial expression? A) Hypoglossal nucleus B) Vestibular nuclei C) Facial nerve nucleus D) Cochlear nuclei The motor nucleus of the facial nerve (CN VII) controls muscles of facial expression. 6 / 10 Which cranial nerve nuclei are located in the medial eminence? A) Facial nerve nucleus B) Vagus nerve nucleus C) Glossopharyngeal nucleus D) Abducens nucleus The abducens nucleus (CN VI) is located in the medial eminence of the rhomboid fossa. 7 / 10 The lateral apertures (Foramina of Luschka) open into which structure? A) Inferior medullary velum B) Central canal C) Cerebellum D) Subarachnoid space The lateral apertures connect the 4th ventricle to the subarachnoid space. 8 / 10 Which cranial nerve nucleus is found in the vagal trigone? A) Abducens nucleus B) Spinal accessory nucleus C) Vagus nucleus D) Hypoglossal nucleus The dorsal nucleus of the vagus nerve lies in the vagal trigone and controls parasympathetic functions. 9 / 10 What is the function of the area postrema? A) Regulates heart rate B) Processes auditory input C) Controls CSF circulation D) Detects toxins and triggers vomiting The area postrema detects toxins in the blood and triggers vomiting, making it part of the circumventricular organs. 10 / 10 What is the primary function of the 4th ventricle? A) CSF circulation B) Sensory processing C) Auditory signal relay D) Motor coordination The 4th ventricle allows CSF circulation between the ventricular system and the subarachnoid space. Your score is The average score is 0% Description Ventricles in the Brain Fourth Ventricle Central Canal Aqueduct of the Midbrain Third Ventricle Interventricular Foramen Lateral Ventricles Contain Cerebrospinal Fluid Subarachnoid Space Roof of 4th Ventricle (Tegmen Ventriculi Quarti) Superior Medullary Velum (Velum Medullare Superius) Inferior Medullary Velum (Velum Medullare Inferius) Tela Choroidea Choroid Plexus Fastigium Communications of 4th Ventricle Aqueduct of Midbrain (Aquaeductus Mesencephali) Lateral Apertures / Foramina of Luschka (Apertura Laterales Ventriculi Quarti) Median Aperture / Foramen of Magendie (Apertura Mediana Ventriculi Quarti) Central Canal (Canalis Centralis) Topography of the Rhomboid Fossa (Fossa Rhomboidea) Bordered by the Superior and Inferior Cerebellar Peduncle Anatomical Structures of the Rhomboid Fossa Median Sulcus (Sulcus Medianus) Medial Eminence (Eminentia Medialis) Medullary Stria (Stria Medullares) Facial Colliculus (Colliculus Facialis) Hypoglossal Trigone (Trigonum Hypoglossi) Vagal Trigone (Trigonum N. Hypoglossi) Vestibular Area (Area Vestibularis) Locus Caeruleus Cranial Nuclei of the Rhomboid Fossa Trigeminal Nerve (N. Trigeminus) Mesencephalic Nucleus of the Trigeminal Nerve (Nucleus Mesencephalicus Nervi Trigemini) Principal Nucleus of Trigeminal Nerve (Nucleus Principalis Nervi Trigemini) Spinal Nucleus of Trigeminal Nerve (Nucleus Spinalis Nervi Trigemini) Motor Nucleus of Trigeminal Nerve (Nucleus Motorius Nervi Trigemini) Abducent Nerve (N. Abducens) Nucleus of Abducent Nerve (Nucleus N. Abducensis) Facial Nerve (N. Facialis) Motor Nucleus of Facial Nerve (Nucleus N. Facialis) Superior Salivatory Nucleus (Nucleus Salivatorius) Nucleus of the Solitary Tract (Nucleus Tractus Solitarii) Vestibulocochlear Nerve (N. Vestibulocochlearis) 2x Cochlear Nuclei (Nuclei Cochlearis) 4x Vestibular Nuclei (Nuclei Vestibularis) Glossopharyngeal Nerve (N. Glossopharyngeus) Inferior Salivatory Nucleus (Nucleus Salivatorius Inferior) Nucleus of the Solitary Tract Nucleus Ambiguus Vagus Nerve (N. Vagus) Posterior Nucleus of Vagus Nerve (Nucleus Posterior Nervi Vagi) Nucleus of the Solitary Tract Nucleus Ambiguus Accessory Nerve (N. Accessorius) Nucleus Ambiguus Spinal Nucleus of Accessory Nerve (Nucleus Spinalis Nervi Accessorii) Spinal Root Cranial Root Hypoglossal Nerve (N. Hypoglossus) Nucleus of Hypoglossal Nerve (Nucleus Nervi Hypoglossi) Quiz Included in the video and on this page. Sources used in this video: Memorix Anatomy 2nd Edition by Hudák Radovan, Kachlík David, Volný Ondřej Biorender University notes and lectures Transcript 0:03 What’s up. Meditay here. Let’s continue the anatomy of the Central Nervous System. 0:08 In this segment, we’ll cover the anatomy of the 4th Ventricle, 0:11 and then we’re going to cover the structures and the cranial nuclei of the rhomboid fossa. 0:16 So the central nervous system consists of two parts: the encephalon and the spinal cord. 0:21 The encephalon is then further divided into specific parts. 0:25 We have the brainstem, which consists of the Medulla, Pons, and the Midbrain or the 0:29 mesencephalon. We have the Cerebellum back here, then the diencephalon and the telencephalon. 0:34 Our focus in this video is going to be the space between these three structures, 0:38 called the 4th Ventricle, and the base of the 4th Ventricle, called Rhomboid Fossa. Which is here. 0:44 So in this video, we’re first going to cover all the ventricles in the brain. 0:48 Then we’re going to cover the border and the communications of the 4th Ventricle. 0:52 After that, we’re going to look at the Topography of the Rhomboid fossa. Then cover the anatomical
Pons
Pons – External and Internal (White & Grey matter) Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 Pons – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 What is the function of the trapezoid body in the pons? A) Sound localization B) Proprioception C) Balance D) Vision The trapezoid body is part of the auditory pathway and is involved in sound localization by transmitting information to the superior olivary nucleus. 2 / 10 Which structure separates the basilar part from the tegmentum of the pons? A) Inferior cerebellar peduncle B) Trapezoid body C) Reticular formation D) Medial lemniscus The trapezoid body separates the basilar part (ventral) and the tegmentum (dorsal) of the pons and is part of the auditory pathway. 3 / 10 The reticular formation in the pons plays a role in which function? A) Sensory relay B) Motor coordination C) Vision D) Sleep and arousal The reticular formation is involved in regulating autonomic functions, arousal, and sleep-wake cycles. 4 / 10 What structure connects the pons to the cerebellum? A) Middle cerebellar peduncle B) Superior cerebellar peduncle C) Inferior cerebellar peduncle D) Medial lemniscus The middle cerebellar peduncle connects the pons to the cerebellum and is involved in motor control. 5 / 10 What is the primary function of the corticospinal tract in the pons? A) Balance B) Voluntary motor commands C) Pain transmission D) Auditory processing The corticospinal tract is part of the pyramidal system and transmits voluntary motor commands from the cerebral cortex to the spinal cord. 6 / 10 What forms the posterior surface of the pons? A) Clivus B) Rhomboid fossa (floor of the fourth ventricle) C) Tentorium cerebelli D) Superior cerebellar peduncles The posterior surface of the pons contributes to the floor of the fourth ventricle and includes cerebellar peduncles. 7 / 10 What forms the medial lemniscus in the pons? A) Pontine nuclei B) Reticular formation C) Internal arcuate fibers D) Spinocerebellar fibers The medial lemniscus is formed by the decussation of the internal arcuate fibers, which carry sensory information. 8 / 10 Which cranial nerves have nuclei located in the pons? A) CN III, IV, VI, XI B) CN IX, X, XI, XII C) CN V, VI, VII, VIII D) CN I, II, VI, VII The trigeminal (V), abducens (VI), facial (VII), and vestibulocochlear (VIII) nerves have nuclei in the pons. 9 / 10 Which structure in the pons plays a role in horizontal eye movement coordination? A) Vestibulospinal tract B) Lateral lemniscus C) Tectospinal tract D) Medial longitudinal fasciculus The medial longitudinal fasciculus (MLF) coordinates horizontal eye movements by connecting cranial nerve nuclei. 10 / 10 What separates the basilar part and tegmentum of the pons? A) Reticular formation B) Medial lemniscus C) Inferior cerebellar peduncle D) Trapezoid body The trapezoid body, a key part of the auditory pathway, separates the ventral basilar part from the dorsal tegmentum. Your score is The average score is 0% Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations Pons – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. Start Become a Member You have to become a member before you can access the Notes and the Quizzes. Membership Plans Description Topography of the Pons Lies above the Medulla, Below Mesencephalon, In front of the Cerebellum Anterior Surface Posterior Surface Anterior Surface of the Pons Basilar Sulcus (Sulcus Basilaris) Middle Cerebellar Peduncles (Pedunculus Cerebellaris Media) Cranial Nerve IV: Nervus Abducens between pyramid and pons Between olives and middle cerebellar peduncles Cranial Nerve VII: Facialis Cranial Nerve VIII: Vestibulocochlearis Surface of Pons: Cranial Nerve V (Trigeminus) Posterior View of Pons Rhomboid Fossa (Fossa Rhomboidea) Cerebellar Peduncles (Pedunculi Cerebelli) Inferior Cerebellar Peduncle Middle Cerebellar Peduncle Superior Cerebellar Peduncle Internal Surface of Pons Cochlear Nerve forms Trapezoid Body (Corpus Trapezoideum) Dorsal Part: Tegmentum of Pons Ventral Part: Basilar Part Gray Matter in Basilar Part of Pons Pontine Nuclei (Nuclei Pontis) For Frontopontine Tract PontoCerebellar Tract (Transverse Pontine Fibers) Cerebellorubral Tract Rubrospinal Tract Gray Matter in Tegmentum of Pons Reticular Formation (Formatio Reticularis) Nuclei of Trapezoid Body (Nuclei Corporis Trapezoideum) Nuclei of the Rhomboid Fossa (Cranial nuclei of X-XII) White Matter of Basilar Part of Pons Pontocerebellar Tract (Transverse Pontine Fibers) Coming from Corticopontine tract Frontopontine Tract Parietopontine Tract Temporopontine Tract Occipitopontine Tract Corticospinal Tract (Tractus Corticospinalis) Corticonuclear Tract (Corticobulbar tract) White Matter in Tegmentum of Pons Ascending Tracts Medial Lemniscus (Lemniscus Medialis) Gracile Fascicle (Fasciculus Gracilis) to Gracile Nucleus Cuneate Fascicle (Fasciculus Cuneatus) to Cuneate Nucleus Medial Lemniscus is formed through Internal Arcuate Fibers (Fibrae Arcuatae Internae) Epicritic Sensibility (Proprioception and Mechanoreception) Spinal Lemniscus (Lemniscus Spinalis) Anterior Spinothalamic Tract (Tractus Spinothalamicus Anterior) Lateral Spinothalamic Tract (Tractus Spinothalamicus Lateralis) Trigeminal Lemniscus (Lemniscus Trigeminalis) Anterior Spinocerebellar Tract (Tractus Spinocerebellaris Anterior) Lateral Lemniscus (Lemniscus Lateralis) From Cochlear Nerve Descending Tracts Vestibulospinal Tract (Tractus Vestibulospinalis) Rubrospinal Tract (Tractus Rubrospinalis) Tectospinal Tract (Tractus Tectospinalis) Reticulospinal Tract (Tractus Reticulospinalis) Medial Longitudinal Fasciculus (Fasciculus Longitudinalis Medialis) QUIZ Sources used in this video: Memorix Anatomy 2nd Edition by Hudák Radovan, Kachlík David, Volný Ondřej Biorender University notes and lectures Transcript 0:03What’s up, Meditay here; let’s continue the anatomy of the Central Nervous System.0:07In this segment, we’ll cover the complete anatomy of Pons0:11So the central nervous system consists of two parts:0:14the encephalon and the spinal cord. The encephalon is then further divided into specific parts.0:20We have the brainstem, which consists of the Medulla, Pons, and the Midbrain or the0:24mesencephalon. We have the Cerebellum back here, then the diencephalon and the telencephalon.0:29Our focus in this video is going to be Pons, which is here.0:33So in this video,
Medulla Oblongata
Medulla Oblongata – External & Internal (White & Grey matter) Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 Medulla Oblongata – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 Which structure separates the gracile and cuneate fasciculi on the posterior medulla? A) Posterolateral sulcus B) Posterior median sulcus C) Anterior median fissure D) Inferior cerebellar peduncle The posterior intermediate sulcus lies between the gracile and cuneate fasciculi. 2 / 10 What is the anatomical landmark on the dorsal surface of the medulla between the cuneate tubercles? A) Gracile fasciculus B) Olives C) Pyramids D) Anterior median fissure The posterior median sulcus separates the gracile tubercles medially. 3 / 10 Where do fibers of the gracile and cuneate fasciculi synapse? A) Vestibular nucleus B) Inferior olivary nucleus C) Nucleus ambiguus D) Spinal trigeminal nucleus They synapse in their respective nuclei, gracile and cuneate. 4 / 10 Where does the medial lemniscus transmit sensory signals after decussation? A) Primary motor cortex B) Visual cortex C) Cerebellum D) Spinal cord It transmits signals to the thalamus for further processing. 5 / 10 Which structure in the medulla is responsible for decussating sensory fibers? A) Spinothalamic tract B) Olives C) Pyramids D) Vestibular nuclei The medial lemniscus is formed after internal arcuate fibers decussate. 6 / 10 Which nuclei are found in the rhomboid fossa of the medulla? A) IX, X B) VII, VIII C) III, IV D) V, VI The cranial nerve nuclei for X, XI, and XII are located in the rhomboid fossa. 7 / 10 Which ascending tract transmits pain and temperature signals in the medulla? A) Posterior spinocerebellar tract B) Anterior corticospinal tract C) Medial lemniscus D) Vestibulospinal tract The lateral spinothalamic tract carries pain and temperature signals. 8 / 10 Which tract transmits proprioceptive signals to the cerebellum through the medulla? A) Lateral corticospinal tract B) Tectospinal tract C) Anterior spinothalamic tract D) Rubrospinal tract The posterior spinocerebellar tract carries proprioceptive signals to the cerebellum. 9 / 10 What is the primary function of the nucleus ambiguus? A) Sensory transmission B) Balance and coordination C) Proprioception D) Reflex integration It provides motor innervation to the pharynx, larynx, and soft palate. 10 / 10 Which cranial nerve exits at the level of the pyramids? A) Vagus nerve B) Accessory nerve C) Glossopharyngeal nerve D) Trigeminal nerve The hypoglossal nerve exits at the level of the pyramids. Your score is The average score is 0% Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations Medulla Oblongata – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. Start Become a Member You have to become a member before you can access the Notes and the Quizzes. Membership Plans Description Topography of the Medulla Oblongata: Lies above the Spinal Cord, Below Pons, In front of the Cerebellum, on Clivus, above Foramen Magnum 2.5 cm length Anterior Surface Posterior Surface Anterior Surface of the Medulla Oblongata: Anterior Median Fissure (Fissura Mediana Anterior) Right Anterolateral Sulcus (Sulcus Anterolateralis Dexter) Left Anterolateral Sulcus (Sulcus Anterolateralis Sinister) Right Posterolateral Sulcus (Sulcus Posterolateralis Dexter) Left Posterolateral Sulcus (Sulcus Posterolateralis Sinister) Pyramids of the Medulla Oblongata (Pyramis Medullae Oblongatae) Contain Decussation of Pyramid (Decussation Pyramidum) Olives of the Medulla (Oliva) Cranial Nerve XII (Hypoglossal Nerve) from Anterolateral Sulci Cranial Nerve IX (Glossopharyngeal Nerve) Cranial Nerve X (Vagus Nerve) Cranial Nerve XI (Accessory Nerve) Posterior View of Medulla Oblongata: Posterior Median Sulcus (Sulcus Medianus Posterior) Gracile Fascicle (Fasciculus Gracilis) Gracile Tubercle (Tuberculum Gracilis) Cuneate Fascicle (Fasciculus Cuneatus) Cuneate Tubercle (Tuberculum Cuneatus) Inferior Cerebellar Peduncle (Pedunculus Cerebellaris Inferior) Gray Matter of Medulla: Gracile Nucleus (Nucleus Gracilis) Cuneate Nucleus (Nucleus Cuneatus) Reticular Formation (Formatio Reticularis) Olivary Nuclei (Nuclei Olivares) Nuclei of the Rhomboid Fossa (Cranial nuclei of IX-XII) Ascending Tracts of Medulla: Gracile Fascicle (Fasciculus Gracilis) to Gracile Nucleus Epicritic Sensibility (Proprioception and Mechanoreceptors) Cuneate Fascicle (Fasciculus Cuneatus) to Cuneate Nucleus External Arcuate Fibers (Fibrae Arcuatae Externae) Internal Arcuate Fibers (Fibrae Arcuatae Internae) Decussation of the Lemnisci (Decussatio Lemnisci Medialis) Medial Lemniscus (Lemniscus Medialis) Anterior Spinocerebellar Tract (Tractus Spinocerebellaris Anterior) Through Inferior Cerebellar Peduncle Posterior Spinocerebellar Tract (Tractus Spinocerebellaris Posterior) Through Superior Cerebellar Peduncle Anterior Spinothalamic Tract (Tractus Spinothalamicus Anterior) Lateral Spinothalamic Tract (Tractus Spinothalamicus Lateralis) Descending Tracts of the Medulla: Corticospinal Tract (Tractus Corticospinalis) Decussation of Pyramids (Decussatio Pyramidum) Lateral Corticospinal Tract Anterior Corticospinal Tract Corticonuclear Tract (Corticobulbar Tract) Vestibulospinal Tract (Tractus Vestibulospinalis) Olivospinal Tract (Tractus Olivospinalis) Olivocerebellar Tract (Tractus Olivocerebellaris) Rubrospinal Tract (Tractus Rubrospinalis) Tectospinal Tract (Tractus Tectospinalis) Lateral Reticulospinal Tract (Tractus Reticulospinalis Lateralis) Medial Reticulospinal Tract (Tractus Reticulospinalis Medialis) Medial Longitudinal Fasciculus (Fasciculus Longitudinalis Medialis) QUIZ Sources used in this video: Memorix Anatomy 2nd Edition by Hudák Radovan, Kachlík David, Volný Ondřej Biorender University notes and lectures Transcript Introduction 0:03 What’s up. Meditay Here. Let’s continue the anatomy of the Central Nervous System. 0:08 In this segment, we’ll cover the complete anatomy of the medulla oblongata. 0:12 So remember, the central nervous system consists of two parts: 0:15 the encephalon and the spinal cord. The encephalon is then further divided into specific parts. 0:21 We have the brainstem, which consists of the medulla, pons, and the midbrain or the 0:25 mesencephalon. We have the cerebellum back here, then the diencephalon and the telencephalon. 0:31 Our focus in this video is going to be the medulla oblongata, which is here. 0:35 So in this video, we’re first going to cover the external surfaces of the medulla. Basically, 0:40 look at its topography and what structures you’ll find from an anterior view and a posterior view. 0:45 Then we’re gonna slice up the medulla
Internal Spinal Cord
Internal Spinal Cord (Gray Matter, White Matter, Funiculus) Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 Internal Spinal Cord – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 What is the function of the medial longitudinal fasciculus (MLF)? A) Pain Modulation B) Eye and Head Coordination C) Motor Output D) Reflex Coordination The MLF coordinates eye and head movements by connecting vestibular nuclei with ocular and cervical motor nuclei. 2 / 10 What is the primary function of the rubrospinal tract? A) Reflex Control B) Pain Transmission C) Proprioception D) Fine Motor Coordination The rubrospinal tract is involved in motor coordination, particularly fine motor movements of the upper limbs. 3 / 10 What type of fibers are found in the anterior horn of the spinal cord? A) Sensory Fibers B) Parasympathetic Fibers C) Motor Fibers D) Sympathetic Fibers The anterior horn contains motor (efferent) fibers that control skeletal muscle. 4 / 10 What is the main function of the cuneate fascicle? A) Fine Touch and Proprioception B) Reflex Control C) Motor Coordination D) Pain and Temperature The cuneate fascicle transmits sensory signals for fine touch, vibration, and conscious proprioception from the upper body. 5 / 10 Which fibers primarily occupy the lateral funiculus? A) Sensory Only B) Reflex Pathways C) Motor Only D) Sensory and Motor Fibers The lateral funiculus contains both ascending sensory tracts and descending motor tracts. 6 / 10 Which tract transmits conscious proprioception from the lower limbs? A) Rubrospinal Tract B) Gracile Fascicle C) Cuneate Fascicle D) Lateral Spinothalamic Tract The gracile fascicle transmits conscious proprioception, vibration, and fine touch from the lower limbs. 7 / 10 Which tracts are found in the posterior funiculus? A) Tectospinal and Rubrospinal Tracts B) Lateral Corticospinal Tracts C) Cuneate and Gracile Fasciculi D) Anterior Spinothalamic Tract The posterior funiculus contains the cuneate and gracile fasciculi, which carry sensory signals for fine touch and proprioception. 8 / 10 Which gray matter region contains sympathetic preganglionic neurons? A) Nucleus Proprius B) Marginal Nucleus C) Intermediolateral Nucleus D) Sacral Parasympathetic Nuclei The intermediolateral nucleus in the lateral horn contains sympathetic preganglionic neurons in the thoracic and lumbar regions. 9 / 10 Which nucleus receives input from visceral sensory fibers? A) Intermediomedial Nucleus B) Gelatinous Substance C) Posterior Thoracic Nucleus D) Marginal Nucleus The intermediomedial nucleus in the intermediate column processes visceral sensory inputs. 10 / 10 What is the primary role of the vestibulospinal tract? A) Balance and Posture B) Motor Coordination C) Pain Modulation D) Reflex Arc The vestibulospinal tract maintains balance and posture by regulating muscle tone. Your score is The average score is 0% Description Internal Surface of Spinal Cord Grey Matter – Nerve Cell Bodies and Dendrites White Matter – Myelinated axons and glial cells Grey Matter of Spinal Cord Anterior Horn (Conu Anterius) Motor Nuclei Posterior Horn (Conu Posterius) Marginal Nucleus (Nucleus Marginalis) Gelatinous Substance of Rolando (Substantia Gelatinosa Rolandi) Nucleus Proprius Posterior Thoracic Nucleus (Nucleus Thoracicus Posterior) Lateral Horn (Conu Lateralis) Sympathetic and Parasympathetic fibers Intermediate Column (Columna Intermedia) Intermediomedial Nucleus (Nucleus Intermediomedialis) Intermediolateral Nucleus (Nucleus Intermediolateralis) Sacral Parasympathetic Nuclei (Nucleus Parasympathetici Sacrales) Central Zone (Zona Centralis) Central Canal (Canalis Centralis) Central Gelatinous Substance of Spinal Cord (Substantia Gelatinosa Centralis) Fasciculi Proprii Spinal Reticular Formation (Formatio Reticulatis Spinalis) White Matter of Spinal Cord Posterior Funiculus Lateral Funiculus Anterior Funiculus White Matter Arrangement Ascending Tracts / Afferent Tracts (Tractus Ascendentes s. Afferentes) Unconscious (to Cerebellum) Unconscious Proprioceptive Sensation (Posture, Joint Stability, Feedforward Control) Anterior Spinocerebellar Tract (Tractus Spinocerebellaris Anterior) Posterior Spinocerebellar Tract (Tractus Spinocerebellaris Posterior) Conscious (to Cortex) Conscious Proprioceptive Sensation (Kinesia, Joint Position, Sense of Force) Touch, Pain, Pressure, Temperature Anterior Spinothalamic Tract (Tractus Spinothalamicus Anterior) Lateral Spinothalamic Tract (Tractus Spinothalamicus Lateralis) Cuneate Fascicle (Fasciculus Cuneatus) Gracile Fascicle (Fasciculus Gracilis) Descending Tracts / Efferent Tracts (Tractus Descendens s. Efferentes) Involuntary Movements (Extrapyramidal Tracts) Balance, Body Posture, Coarse Movements Rubrospinal Tract (Tractus Rubrospinalis) Tectospinal Tract (Tractus Tectospinalis) Vestibulospinal Tract (Tractus Vestibulospinalis) Olivospinal Tract (Tractus Olivospinalis) Medial Reticulospinal Tract (Tractus Reticulospinalis Medialis) Lateral Reticulospinal Tract (Tractus Reticulospinalis Lateralis) Voluntary Movements (Pyramidal Tracts) From Pyramidal Cells of Primary Motor Cortex Anterior Corticospinal Tract (Tractus Corticospinalis Anterior) Lateral Corticospinal Tract (Tractus Corticospinalis Lateralis) Posterior Funiculus Cuneate Fascicle (Fasciculus Cuneatus) Gracile Fascicle (Fasciculus Gracilis) Epicritic Sensibility (Proprioception and Mechanoreceptors) Lateral Funiculus Anterior Spinocerebellar Tract (Tractus Spinocerebellaris Anterior) Posterior Spinocerebellar Tract (Tractus Spinocerebellaris Posterior) Lateral Spinothalamic Tract (Tractus Spinothalamicus Lateralis) Lateral Corticospinal Tract (Tractus Corticospinalis Lateralis) Rubrospinal Tract (Tractus Rubrospinalis) Lateral Reticulospinal Tract (Tractus Reticulospinalis Lateralis) Anterior Funiculus Anterior Spinothalamic Tract (Tractus Spinothalamicus Anterior) Anterior Corticospinal Tract (Tractus Corticospinalis Anterior) Tectospinal Tract (Tractus Tectospinalis) Reflexes associated with eyes and neck Vestibulospinal Tract (Tractus Vestibulospinalis) Balance and Posture Olivospinal Tract (Tractus Olivospinalis) Balance and Posture Medial Reticulospinal Tract (Tractus Reticulospinalis Medialis) Medial Longitudinal Fasciculus (Fasciculus Longitudinalis Medialis) QUIZ Sources used in this video: Memorix Anatomy 2nd Edition by Hudák Radovan, Kachlík David, Volný Ondřej Biorender University notes and lectures Transcript 0:03 What’s up. Meditay Here. 0:05 Let’s talk about the anatomy of the Central Nervous System. 0:08 In this segment, we will be talking about the Internal surface of the Spinal Cord. Basically go through 0:13 everything you need to know regarding the anatomy of the tracts and nuclei within the spinal Cord. 0:18 Alright, so the Central Nervous System consists of two parts. The encephalon and the spinal Cord 0:24 So in this is video, we’re first going to go through the internal surface of the Spinal Cord 0:29 and talk about the distribution of white and grey matter within it. Then we’ll look detailed into 0:34 the anatomy of the grey matter and the anatomy of the white matter. Then at the end of this video, 0:39 I’ve made a quiz which you’ll hopefully be able to pass based
External Spinal Cord
External Spinal Cord (Surface, Segments, Spinal Nerve, Enlargements, Reflex Arch) Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 External Spinal Cord – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 What is the anatomical significance of the cervical enlargement? A) Brachial Plexus B) Cervical Plexus C) Lumbosacral Plexus D) Thoracic Plexus The cervical enlargement provides neural input and output for the upper limbs through the brachial plexus. 2 / 10 How many cervical segments are there in the spinal cord? A) 7 B) 6 C) 8 D) 9 There are 8 cervical spinal cord segments, corresponding to the cervical nerves. 3 / 10 What is the name of the bundle of nerve roots extending beyond the medullary cone? A) Cauda Equina B) Spinal Ganglia C) Filum Terminale D) Medullary Cone The cauda equina consists of lumbar, sacral, and coccygeal nerve roots extending beyond the medullary cone. 4 / 10 Where does the spinal cord typically terminate in adults? A) L3–L4 B) T12–L1 C) L1–L2 D) L2–L3 The spinal cord ends around the level of the L1–L2 vertebrae in adults. 5 / 10 How many spinal cord segments are there in total? A) 32 B) 30 C) 31 D) 33 The spinal cord consists of 31 segments: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. 6 / 10 What is the name of the canal through which the spinal cord runs? A) Central Canal B) Intervertebral Foramina C) Vertebral Canal D) Neural Canal The spinal cord runs through the vertebral canal, formed by the vertebrae. 7 / 10 What is the length of the spinal cord in adults? A) 30–35 cm B) 45–50 cm C) 40–45 cm D) 50–55 cm The spinal cord is approximately 40–45 cm long in adults, extending from the foramen magnum to the L1–L2 vertebral level. 8 / 10 Which layer of meninges provides direct vascular support to the spinal cord? A) Arachnoid Mater B) Dura Mater C) Epidural Layer D) Pia Mater The pia mater is the innermost meningeal layer that provides vascular support to the spinal cord. 9 / 10 What type of fibers are present in spinal nerves between C8 and L2? A) Sensory Fibers B) Motor Fibers C) Parasympathetic Fibers D) Sympathetic Fibers Sympathetic fibers, part of the autonomic nervous system, are present in spinal nerves between C8 and L2. 10 / 10 What is the function of the posterior median sulcus? A) Support Vasculature B) Divide the Spinal Cord Dorsally C) Conduct Motor Signals D) Conduct Reflexes The posterior median sulcus is a shallow groove that partially divides the spinal cord into left and right halves dorsally. Your score is The average score is 0% Description Topography of Spinal Cord (Medulla Spinalis) Vertebral Canal (Canalis Vertebralis) Covered by: Pia Mater Arachnoid Mater Dura Mater Foramen Magnum to L1/L2 40-45 cm long Medullary Cone (Conus Medullaris) Filum Terminale (Terminal Thread) Cauda Equina External Surface of Spinal Cord: Anterior Surface: Anterior Median Fissure (Fissura Mediana Anterior) Right Anterolateral Sulcus (Sulcus Anterolateralis Dexter) Left Anterolateral Sulcus (Sulcus Anterolateralis Sinister) Posterior Surface: Posterior Median Sulcus (Sulcus Medianus Posterior) Right Posterolateral Sulcus (Sulcus Posterolateralis Dexter) Left Posterolateral Sulcus (Sulcus Posterolateralis Sinister) Segments of the Spinal Cord 8 cervical segments 12 thoracic segments 5 lumbar segments 5 sacral segments 1 coccygeal segment Spinal nerves exit through Intervertebral Openings (Foramina Intervertebralis) Relationship between the Spinal Cord and the Vertebra: Spinous processes of cranial cervical vertebrae – Correspond to the same segment Spinous processes of caudal cervical vertebrae – Segment +1 (e.g. vertebra C7 = spinal segment C8) Spinous processes of cranial thoracic vertebrae – Segment +2 (e.g. vertebra T3 = spinal segment T5) Spinous processes of caudal thoracic vertebrae – Segment +3 Vertebrae T10–T12 – Lumbar segments L1–L4 Vertebrae T12–L1 (epiconus) – Lumbar and sacral segments L5–S2 Vertebrae L1–L2 (conus) – Sacral and single coccygeal segments S3–S5 and Co Enlargements of the Spinal Cord Cervical Enlargement (Intumenencia Cervicalis) Brachial Plexus Lumbosacral Enlargement (Intumenencia Lumbosacralis) Sacral and Lumbar Plexuses Anatomy of the Spinal Nerve: Spinal Nerves synapse with nuclei in gray matter of the spinal cord Posterior Root / Sensory Root (Radix Sensoria) Enter through the posterolateral sulci Spinal Ganglion / Dorsal Root Ganglion (Ganglion sensorium nervi spinalis) Pseudounipolar neurons Anterior Root / Motor Root (Radix Motoria) Enter through the anterolateral sulci Spinal Nerve contains: Sensory Fibers Motor Fibers Sympathetic Fibers (Between C8-L2) Parasympathetic Fibers (Between S2-S4) Branches of the Spinal Nerve: Ventral Branch Cervical Plexus Brachial Plexus Lumbar Plexus Sacral Plexus Dorsal Branch White Ramus Communicans Meningeal Branch Reflex Arch Mono-Synaptic Reflex Patellar Tendon Reflex Multi-Synaptic Reflex Withdrawal Reflex Sources used in this video: Memorix Anatomy 2nd Edition by Hudák Radovan, Kachlík David, Volný Ondřej Biorender University notes and lectures Transcript Introduction0:03What’s up. Meditay here. Let’s talk about the anatomy of the Central Nervous System.0:08In this segment, we will be talking about the external anatomy of the spinal cord.0:12basically, go through everything you need to know in regards to what the spinal cord is0:16and what you’ll find grossly on the spinal cord. Alright, so the Central Nervous System consists of0:22two parts. The encephalon, and the spinal cord. So in this is video, we’re first going0:27to go through the Topography of the Spinal cord, basically where it is,0:31where it starts and ends. Then we’ll focus on the external surface of the spinal cord,0:36basically going through all the grooves and fissures you see there. We’re also going to go0:40through the segments of the spinal cord and look at its relationship with the vertebral column.0:46Then we’ll go through the enlargements we see on the spinal cord. After that we’ll look at0:51the anatomy of a spinal nerve, and understand its 4 branches, and then quickly understand the0:56types of reflex arches we can have through the spinal cord.
Central Nervous System Overview
Central Nervous System Overview (Pars, Neurons, Neuroglia, White & Grey Matter, Development) Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 CNS Overview – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 What are the three parts of the brainstem? A) Diencephalon, midbrain B) Medulla oblongata, pons, midbrain C) Telencephalon, medulla D) Cerebellum, midbrain The brainstem consists of the medulla oblongata, pons, and midbrain. 2 / 10 Which spinal cord region is primarily involved in autonomic functions? A) Thoracic region B) Cervical region C) Lumbar region D) Sacral region The thoracic region of the spinal cord houses autonomic nuclei for sympathetic outflow. 3 / 10 Which layer of the meninges is directly in contact with the brain? A) Pia mater B) Subarachnoid space C) Dura mater D) Arachnoid mater The pia mater is the innermost layer of the meninges, adhering closely to the brain’s surface. 4 / 10 Which neuroglia type is responsible for lining the ventricles of the brain? A) Ependymal cells B) Oligodendrocytes C) Microglia D) Astrocytes Ependymal cells line the ventricles and central canal, facilitating cerebrospinal fluid production and movement. 5 / 10 During CNS development, which vesicle forms the thalamus? A) Rhombencephalon B) Myelencephalon C) Diencephalon D) Mesencephalon The thalamus develops from the diencephalon. 6 / 10 Which structure controls basic autonomic functions like breathing and heart rate? A) Medulla oblongata B) Midbrain C) Cerebellum D) Pons The medulla oblongata controls autonomic functions such as breathing and heart rate. 7 / 10 Which type of neuron is responsible for motor output from the CNS? A) Efferent neurons B) Bipolar neurons C) Interneurons D) Afferent neurons Efferent (motor) neurons carry signals from the CNS to muscles and glands. 8 / 10 What is the primary role of astrocytes in the CNS? A) CSF production B) Immune response C) Myelination D) Blood-brain barrier Astrocytes provide mechanical support and help form the blood-brain barrier. 9 / 10 What is the role of oligodendrocytes in the CNS? A) Myelination B) Immune response C) Supporting capillaries D) Producing CSF Oligodendrocytes are responsible for forming myelin sheaths around CNS axons. 10 / 10 During which embryonic week does the CNS divide into its main vesicles? A) Week 4 B) Week 5 C) Week 6 D) Week 3 The CNS divides into its main vesicles during week 4 of embryonic development. Your score is The average score is 0% Description Central Nervous System Parts: The Brain (Encephalon) Medulla Oblongata Pons Mesencephalon Cerebellum Diencephalon Telencephalon Spinal Cord (Medulla Spinalis) Neurons: Neurons form Nerve Tissue Dendrites Cell body (nucleus) Axons Axon Terminal CNS: Oligodendrocytes PNS: Schwann Cells Myelin Sheath Histology: Granules, demarcation between axon and body Multipolar Neuron Pseudounipolar Neuron Bipolar Neuron Neuron Function: Afferent (Sensory) Nerve Interneuron Efferent (Motor) Nerve Neuroglia: Give mechanical support and provide nutrients Astrocytes form the Blood-Brain Barrier Oligodendrocytes (myelination) Microglia (Immune Cells) Ependymal Cells (Lines cavities in the brain and spinal cord) Distribution of White and Grey Matter in the CNS: Grey Matter (Rich in Nerve body and Dendrites) White Matter (Myelinated Axons) Cross Sections of the Spinal Cord Grey matter in centrum and white matter around Cross Sections of the Brain Grey matter in cortex and in the middle, white matter in between Nerve Tracts (Tractus Nervosi): Bundle of axons that connect gray matter to gray matter Classification: Association Fibers Commissural Fibers Projection Fibers Classification: Ascending Tracts Descending Tracts Indirect Tracts Development of Central Nervous System: Week 4 after fertilization Spinal Cord Rhombencephalon (Hindbrain) Mesencephalon (Midbrain) Prosencephalon (Forebrain) Week 5 after fertilization Spinal Cord Myelencephalon Metencephalon Mesencephalon (Midbrain) Diencephalon Telencephalon Sources used in this video: Memorix Anatomy 2nd Edition by Hudák Radovan, Kachlík David, Volný Ondřej Biorender University notes and lectures Transcript Introduction0:03What up. Meditay here. Let’s talk about the anatomy of the Central Nervous System.0:08In this segment, we will go through the base in understanding how the anatomy of the CNS is built.0:14And to do that, we’ll first go through the Parts of the CNS, then we’re going to go through the0:20microscopic structures of the central nervous system, basically understand what Neurons and0:23Neuroglia are and how they’re distributed in the CNS. After that, we’ll be talking about0:29the distribution of white and grey matter and talk about nerve tracts. And then end by talking0:34about the general nervous system development. Alright, so the central nervous system consistsParts of the Central Nervous System0:39of two main parts. There’s the Encephalon or the brain. And then the Spinal Cord.0:45But the brain is also divided into functionally different parts,0:49so if we look here, we have the spinal cord. And then, above the spinal cord,0:53we’ll find a structure called the brainstem And the brainstem consists of the Medulla,0:57or Medulla Oblongata, The Pons, and the Mesencephalon. Behind the brainstem,1:03we’ll find the Cerebellum, which is an essential part of the brain for muscle memory. Above that,1:08there’s the Diencephalon, which’s the area you’ll find the hypothalamus. And then we have the1:14Telencephalon, which is what we call the highest order in our brain where our personality is.1:20And so the way all of this works is that Nerves pass signals towards the higher senses of the1:25brain, then there are nerves that interpret the signals, which then generate an impulse, basically1:30activating neurons that send signals towards a muscle or an organ to activate a response.Neurons1:36And so I say neurons because that’s the primary type of cells in our Nervous System. If we take1:42a segment of the spinal cord and look at it underneath a microscope, you’ll see1:46that they’re composed of nerve tissue. And if we take a small segment of the nerve tissue,1:51you’ll find a lot of these cells we call a Neuron. Let’s talk about the neuron a little bit. Here1:57you see a simple animated neuron. They consist of Dendrites. Dendrites are what receive signals and2:03send them
Peripheral Nervous System Overview
Peripheral Nervous System Overview (Classification, Spinal Nerve) + Clinical Relevance Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 Peripheral Nervous System Overview – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 What is the difference between white and gray rami communicantes? A) White: sensory; Gray: motor B) White: pre-ganglionic; Gray: post-ganglionic C) Both carry motor fibers D) Both carry sensory fibers White rami communicantes carry pre-ganglionic fibers, while gray rami communicantes carry post-ganglionic fibers. 2 / 10 What is the function of proprioceptors? A) Respond to external stimuli B) Signal changes in temperature C) Detect changes in organ function D) Monitor body position and movement Proprioceptors detect body position and movement, providing sensory input from muscles, tendons, and joints. 3 / 10 What structure connects the posterior and anterior roots of the spinal nerve? A) White ramus communicans B) Dorsal root ganglion C) Sympathetic trunk D) Spinal nerve trunk The trunk of the spinal nerve (truncus nervi spinalis) is formed by the merging of the anterior and posterior roots. 4 / 10 What is the function of the posterior branch of the spinal nerve? A) Transmit sensory input B) Innervate deep back muscles C) Carry autonomic signals D) Innervate limbs The posterior branch innervates the deep back muscles and the overlying skin. 5 / 10 Which spinal nerve branch provides innervation to the meninges? A) Meningeal branch B) Sympathetic branch C) Anterior branch D) Posterior branch The meningeal branch innervates the meninges and vertebral column. 6 / 10 Where do pre-ganglionic sympathetic fibers originate? A) Lateral horn (C8-L2) B) Posterior horn C) Brainstem D) Anterior horn Pre-ganglionic sympathetic fibers originate in the lateral horn of the spinal cord from levels C8-L2. 7 / 10 Which cranial nerve is responsible for tongue movement? A) Hypoglossal nerve B) Trigeminal nerve C) Vagus nerve D) Glossopharyngeal nerve The hypoglossal nerve (cranial nerve XII) controls motor functions of the tongue. 8 / 10 What structure houses the sensory neuron cell bodies in the spinal nerve? A) Spinal ganglion B) White ramus communicans C) Sympathetic trunk ganglion D) Trunk of spinal nerve The spinal ganglion (ganglion sensorium nervi spinalis) is located in the dorsal root and houses sensory neuron cell bodies. 9 / 10 What is the anatomical name for the anterior root of the spinal nerve? A) Ramus posterior B) Radix posterior C) Ramus anterior D) Radix anterior The anterior root is also called the radix anterior and carries motor fibers. 10 / 10 How many nerve pairs form the brachial plexus? A) 6 B) 4 C) 3 D) 5 The brachial plexus is formed by the anterior branches of C5-T1 spinal nerves. Your score is The average score is 0% Description What is the Peripheral Nervous System? Cranial Nerves 12 nerve pairs Spinal Nerves 31 nerve pairs Classification of the PNS Sensory System Soamtic Sensory Fibers Visceral Sensory Fibers Exteroreceptors, Proprioreceptors, Periosteum Motor System Somatomotor System (Somatic system) Voluntary control Autonomic Nervous System / Visceromotor nervous system Sympathetic Nervous System (C8-L2 Lateral horn) Parasympahetic Nervous System (S2-S4 Lateral horn) Enteric Nervous System (myenteric and submucosal plexuses in walls of digestive organs) Clinical Significance Lower Motor Neuron damage Located in anterior horn of spinal cord and nuclei of cranial nerves Damage to lower motor neurons: Flaccid Paralysis Hypotonia Paresis/Plegia Hyporeflexia / areflexia Upper Motor Neuron damage May rise after a stroke or a perinatal hypoxia Spastic Paralysis Paresis / Plegia Hypertonia Hyperreflexia Babinski’s sign External Scheme of Spinal Nerve Rootlets (fila radicularia) Anterior root (radix anterior) Posterior root (radic posterior) Spinal Ganglion (ganglion sensorium nervi spinalis) Trunk of Spinal Nerve (truncus nervi spinalis) Posterior Branch (Ramus posterior) Anterior Branch (ramus anterior) Meningeal branch (ramus meningeus) Ganglion of sympathetic trunk (ganglion trunci sympathici) Gray ramus communicans White ramus communicans (ramus communicans albus) Internal Scheme of Spinal Nerve Somatomotor fibers Pre-ganglionic sympathetic fibers (Visceromotor fibers) Post-ganglionic Fibers Pre-ganglionic parasympathetic fibers Somatosensory fibers Viscerosensory fibers (baroreceptors, chemoreceptors, unspecific organ senstation) Posterior Branch: Suboccipital Nerve (nervus suboccipitalis) C1 Greater Occipital Nerve (nervus occipitalis major) C2 Occipital Nerve (nervus occipitalis tertius) C3 Superior Clunial Nerve (Nervi Clunium Superiores) L1-L3 Middle Clunial Nerves (Nervi Clunium Medii) S1-S3 Anterior Branch: Cervical Plexus (Plexus cervicalis) C1-C4 Brachial Plexus (Plexus brachialis) C4-T1 Thoracic Nerves (Nervi thoracici) T1-T12 Lumbar Plexus (Plexus Lumbalis) T12-L4 Sacral Plexus (Plexus Sacralis) L4-S4 Transcript Introduction0:06What’s up!0:07Taim Talks Med here.0:08Let’s talk about the Peripheral Nervous System!0:11This video is going to be an overview of the peripheral nervous system.0:15So all I’ve done is gather the information that will help you build a general mind map0:19around this topic.0:21So if you’re new to the PNS, I highly recommend you watch this video before you start studying0:27any plexuses or nerves.0:29With that being said, What we’re going to go through is the first0:32talk a little bit about what is considered the PNS0:36We’re gonna go through the classification of the PNS, where we will be talking a little0:41bit about the difference between motor and sensory nerves and the difference between0:46autonomic and somatic nerves.0:48Then we’ll make a simple outline of a spinal nerve.0:52We’re first gonna make an external scheme of the spinal nerve, then an internal scheme0:57of the spinal nerve.What is Considered the PNS?0:59Awesome.1:00So, what is considered the PNS?1:03I guess at this point, since you’re studying the PNS, you already know that the brain and1:08the spinal cord are considered the central nervous system.1:12That means that all the nerves that exit the brain and the spinal cord are considered the1:17PNS.1:19What do you call the nerves that exit the brain and the spinal cord?1:24Nerves exit the brain within the cranium.1:26They’re called cranial nerves.1:28Nerves exit the spinal cord; they’re called spinal nerves.1:32Easy.1:33These Nerves enable bidirectional communication between the central nervous system and the1:39rest of the body, which is referred to as the periphery.1:42There are 31 pairs of
Muscles of Mastication
Muscles of Mastication (Origin, Insertion, Function) Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 Muscles of Mastication – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 What structure forms the origin of the deep part of the masseter muscle? A) Deep surface of zygomatic arch B) Temporal fossa C) Lateral plate of pterygoid process D) Infratemporal crest The deep part of the masseter muscle originates from the deep surface of the zygomatic arch. 2 / 10 What is the insertion point of the temporal muscle? A) Coronoid process B) Masseteric tuberosity C) Mandibular angle D) Pterygoid fovea The temporal muscle inserts onto the coronoid process of the mandible. 3 / 10 Which muscle originates from the maxillary tuberosity and pterygoid fossa of the sphenoid bone? A) Medial pterygoid B) Lateral pterygoid C) Masseter D) Temporal muscle The medial pterygoid muscle originates from the maxillary tuberosity (superficial head) and the pterygoid fossa (deep head). 4 / 10 Which muscle has its origin on the temporal fossa and inserts onto the coronoid process of the mandible? A) Temporal muscle B) Lateral pterygoid C) Masseter D) Medial pterygoid The temporal muscle originates from the temporal fossa and inserts onto the coronoid process of the mandible. 5 / 10 What is the insertion of the masseter muscle? A) Mandibular angle B) Masseteric tuberosity C) Pterygoid fovea D) Coronoid process The masseter inserts into the masseteric tuberosity of the mandible. 6 / 10 What is the function of the medial pterygoid muscle during bilateral contraction? A) Retracts the mandible B) Elevates the mandible C) Depresses the mandible D) Protracts the mandible The medial pterygoid muscle elevates the mandible during bilateral contraction. 7 / 10 Which muscle originates from the zygomatic arch and inserts into the masseteric tuberosity? A) Masseter B) Medial pterygoid C) Temporal muscle D) Lateral pterygoid The masseter muscle originates from the zygomatic arch and inserts into the masseteric tuberosity. 8 / 10 Which muscle inserts into the pterygoid fovea on the neck of the mandible? A) Masseter B) Medial pterygoid C) Temporal muscle D) Lateral pterygoid The lateral pterygoid muscle inserts into the pterygoid fovea on the mandible’s neck. 9 / 10 Which nerve innervates all the muscles of mastication? A) Glossopharyngeal nerve (CN IX) B) Mandibular nerve (CN V3) C) Facial nerve (CN VII) D) Hypoglossal nerve (CN XII) All muscles of mastication are innervated by the mandibular nerve, a branch of the trigeminal nerve (CN V3). 10 / 10 What is the insertion point of the lateral pterygoid muscle? A) Mandibular angle B) Coronoid process C) Pterygoid fovea D) Masseteric tuberosity The lateral pterygoid muscle inserts into the pterygoid fovea of the mandible. Your score is The average score is 0% Description In this video, I go through the Muscles of Mastication, covering their origin, insertion, and function. Understanding these muscles is essential for comprehending jaw movements and chewing mechanics. Muscles of Mastication Temporal Muscle (Musculus Temporalis) Origin: Temporal fossa Parietal bone – Inferior temporal line Insertion: Coronoid process of the mandible (Processus coronoideus mandibulae) Function: Elevates mandible (Anterior fibers) Retracts mandible (Posterior fibers) Masseter Muscle (Musculus Masseter) Origin: Zygomatic Arch (Arcus zygomaticus) Insertion: Masseteric tuberosity of mandible (Tuberositas masseterica mandibulae) Function: Elevates mandible Medial Pterygoid Muscle (Musculus Pterygoideus Medialis) Origin: Superficial Part (Pars superficialis): Maxillary tuberosity (Tuberositas maxillae) Deep Part (Pars profunda): Pterygoid fossa of pterygoid process (Fossa pterygoidea ossis sphenoidalis) Function: Elevates mandible (Bilateral contraction) Frictional masticatory movement (Unilateral contraction) Lateral Pterygoid Muscle (Musculus Pterygoideus Lateralis) Origin: Superior Head (Caput superius): Infratemporal surface + Sphenoid Bone (Greater Wing) (Facies infratemporalis + alae majoris ossis sphenoidalis) Inferior Head (Caput inferius): Lateral lamina of pterygoid process (Sphenoidal bone) (Lamina lateralis processus pterygoidei) Insertion: Pterygoid fovea of the mandible (Fovea pterygoidea mandibulae) Function: Pushes mandible forward (Bilateral contraction) Frictional masticatory movement (Unilateral contraction) Transcript Introduction0:03Hey, what’s up. Meditay here and this.. is my first video of the muscular anatomy series.0:08So in this segment, we’re gonna cover all muscles of mastication. Which are a part0:13of the muscles of the head. Alright so All muscles of the head are divided into0:18two groups. The first group is the muscles of mastication. Mastication means to chew,0:23so those are the muscles responsible for chewing when you’re eating. And the second group is gonna0:28be fascial muscles or the muscles that are gonna be responsible for facial expression. So0:33we’re gonna focus on the mastication muscles here. So in this video, we’re gonna cover the origin and0:38insertion points of the 4 muscles of mastication, which are the Temporal, Masseter, Medial0:44Pterygoid, and Lateral Pterygoid muscles. And then in the next video, we’ll cover the facial muscles.0:50Alright. Before we start, I want you to have some basic understandingParts of Skeletal Muscle0:55of what makes up the different parts of a muscle. All the muscles in our body consist of an Origin1:01point, which is the part of the muscle that’s attached to a bone that does not move or move1:06a very slightly bit during contraction. It has a head, which is the proximal part of the muscle,1:11there’s a belly which is the widest part of the muscle. Then there’s a tail and an Insertion1:17point, which is the part of the muscle that’s attached to a bone that moves during contraction.1:22When you’re studying muscles in general, the origin and insertion points are what we1:27usually focus on. And again keep in mind that the origin point is the least movable part,1:32and the insertion point is the part of the bone that is moved during contraction.1:37In some locations you’ll also see the word belly, usually if the muscle is divided into two parts,1:42that’s when we mention this term. Awesome. Let’s now cover the muscles of mastication.Muscles of Mastication1:47The muscles of mastication again, consist of the temporal muscle. Masseter muscle, Medial Pterygoid1:53muscle, and Lateral
Sympathetic Nervous System
Sympathetic Nervous System (Ganglia, Neurons, Plexuses) Official Links Instagram Youtube Jki-discord Notes & Illustrations Quizzes Summary & Transcript Notes ☆ Members Only Go to PDF Notes Illustrations ☆ Members Only Go to Illustrations 12345678910 Sympathetic Nervous System – QUIZ Test your understanding with 10 random multiple-choice questions from the question bank. You're in the preview mode. Note: All elements work correctly on the front end. 1 / 10 What is the effect of sympathetic stimulation on the heart? A) Bronchoconstriction B) Vasodilation C) Decrease in heart rate D) Increase in heart rate Sympathetic stimulation increases heart rate and myocardial contractility via β1-adrenergic receptors. 2 / 10 Which plexus regulates bronchodilation? A) Hypogastric plexus B) Pulmonary plexus C) Cardiac plexus D) Celiac plexus The pulmonary plexus regulates bronchodilation during sympathetic activation. 3 / 10 Which nerve contributes to the pulmonary plexus? A) Greater splanchnic nerve B) Lumbar splanchnic nerve C) Thoracic splanchnic nerves D) Sacral splanchnic nerve Thoracic splanchnic nerves contribute to the pulmonary plexus. 4 / 10 What is the primary function of the superior cervical ganglion? A) Supplies the pelvis B) Supplies the head and neck C) Supplies the abdomen D) Supplies the thorax The superior cervical ganglion supplies sympathetic innervation to the head and neck. 5 / 10 What is the function of alpha-1 adrenergic receptors in the sympathetic system? A) Vasoconstriction B) Bronchoconstriction C) Vasodilation D) Bronchodilation Alpha-1 adrenergic receptors cause vasoconstriction to increase blood pressure. 6 / 10 Which nerve supplies sympathetic innervation to the kidneys? A) Least splanchnic nerve B) Greater splanchnic nerve C) Lumbar splanchnic nerve D) Lesser splanchnic nerve The least splanchnic nerve provides sympathetic innervation to the kidneys. 7 / 10 What is the role of grey rami communicantes? A) Carry postganglionic fibers to spinal nerves B) Connect the sympathetic trunk to the adrenal medulla C) Regulate neurotransmitter release D) Carry preganglionic fibers to ganglia Grey rami communicantes carry unmyelinated postganglionic fibers to spinal nerves. 8 / 10 Which ganglion is part of the cervical sympathetic trunk? A) Celiac ganglion B) Superior mesenteric ganglion C) Superior cervical ganglion D) Inferior hypogastric ganglion The superior cervical ganglion is located at the top of the sympathetic trunk in the neck. 9 / 10 Which sympathetic ganglion is associated with the cardiac plexus? A) Lumbar ganglion B) Thoracic ganglion C) Coccygeal ganglion D) Cervical ganglion The thoracic ganglia provide sympathetic fibers to the cardiac plexus, affecting heart function. 10 / 10 Which ganglia are part of the prevertebral sympathetic ganglia? A) Celiac, superior, and inferior mesenteric ganglia B) Sacral ganglia C) Cervical ganglia D) Thoracic ganglia The celiac, superior mesenteric, and inferior mesenteric ganglia are prevertebral ganglia. Your score is The average score is 0% Description Sympathetic Nervous System; A system of fight or flight, that increases energy expenditure and catabolism. It increases heart rate and myocardial contractility, dilates bronchi, increases blood pressure and indirectly increases blood glucose and lipid levels. It’s a part of the autonomic nervous system, which is under the motor division of peripheral nervous system. General Structures and terms: Group of cell bodies in CNS – Nucleus Group of cell bodies outside CNS – Ganglion Paravertebral ganglia Prevertebral ganglia Presynaptic neuron is a cholinergic neuron (Ach binds to nicotinic receptors, allowing an influx of cations) Postganglionic neurons are primarily adrenergic neurons (norepinephrine and epinephrine binds to adrenergic receptors, activating g-protein) Sympathetic Preganglionic Neurons: Arise from intermediolateral nuclei (C8/T1–L2/L3) White rami communicantes (rami communicantes albi) myelinated axons from the intermediolateral nucleus that enter the sympathetic trunk. Then: May terminate in the sympathetic ganglion at the same level May travel up or down the sympathetic trunk to terminate in ganglia at a higher or lower level May leave the sympathetic trunk to terminate in a peripheral ganglion Sympathetic Postganglionic neurons: Grey rami communicantes (rami communicantes grisei) Join spinal nerves and innervate cutaneous glands and erector pili muscle. Vascular branches Travel with arteries to provide sympathetic innervation of organs and limbs Visceral branches and splanchnic nerves (rami viscerales, nervi splanchnici) travel towards the organs Sympathetic Trunk: Cervical ganglia (ganglia cervicalia) Superior cervical ganglion Middle cervical ganglion Inferior cervical ganglion aka Cervicothoracic, stellate ganglion Thoracic ganglia (ganglia thoracica) Lumbar ganglia (ganglia lumbalia) Sacral ganglia (ganglia sacralia) Coccygeal ganglia, often fused to form ganglion impar (unpaired). Innervation of Head, Neck and Thorax: Superior Cervical postganglionic fibers: Grey rami communicans join the first 4 cervical nerves Internal carotid nerve (nervus caroticus internus) External carotid nerves (nervi carotici externi) Laryngopharyngeal branches (rami laryngopharyngei) Superior cervical cardiac nerve (nervus cardiacus cervicalis superior) Middle cervical postganglionic fibers: Grey rami communicans join 5th and 6th cervical nerves Visceral branches (rami viscerales) Middle cervical cardiac nerve (nervus cardiacus cervicalis medius) Inferior cervical postganglionic fibers Grey rami communicans join C7, C8 and T1 Vertebral nerve (nervus vertebralis) Inferior cervical cardiac nerve (nervus cardiacus cervicalis inferior) Thoracic ganglia Gray rami communicans join intercostal nerves Thoracic cardiac nerves (nervi cardiaci thoracici) form Cardiac plexus to increase contractility and heart rate Pulmonary branches (rami pulmonales) form pulmonary plexus to cause bronchodilation Oesophageal branches (rami oesophagei) form esophageal plexus to decrease peristalsis Innervation of abdomen and pelvis: Preganglionic fibers go towards prevertebral ganglia Greater splanchnic nerve (nervus splanchnicus major) travel towards celiac ganglia (ganglion ciliare), postganglionic fibers go through plexuses and reach proximal organs in abdomen Preganglionic fibers of greater splanchnic nerve go directly to renal medulla Lesser splanchnic nerve (nervus splanchnicus minor) towards superior mesenteric ganglion for the duodenum, small intestine, large intestine until proximal 2/3. Least splanchnic nerve (nervus splanchnicus imus) go towards the aorticorenal ganglion then towards the kidneys and the ureter Lumbar splanchnic nerves (nervi splanchnici lumbales) go towards the inferior mesenteric ganglia, then towards rest of large intestine, urinary bladder and genitalia Sacral splanchnic nerves (nervi splanchnici sacrales) Sources: Singh, I. (2017). Human neuroanatomy (10th ed) Kozlowski, T. (2017). Memorix Anatomy 2nd ed Gray’s Anatomy: The Anatomical Basis of Clinical Practice (42th ed.) Sinnatamby, Chummy S. (2011). Last’s Anatomy (12th ed.) Yan FL, Zhang JH. Role of the sympathetic nervous system