Basic Strucrure ofBrain Stem1. Roof Plate2. Tegmentum3. Basal Portion

Basilar (Basal) Portion Descending Fibers from Cerebral Cortex1. Corticospinal Tract2. Corticobulbar Tract3. Corticopontocerebellar Fiber Corticopontine Fiber Pons Proper (Ventral Pons) Pontocerebellar FiberPyramidal Tract

Corticospinal Tract

Origin: Cerebral Cortex Brodmann Area 4 (Primary Motor Area, M I) Brodmann Area 6 (Premotor Area, PM ) Brodmann Area 3,1,2 (Primary Somesthetic Area, S I) Brodmann Area 5 (Anterior Portion of Sup. Parietal Lobule) Corona Radiata lnternal Capsule, Posterior Limb Crus Cerebri, Middle Portion Longitudinal Pontine Fiber Pyramid - pyramidal decussation Corticospinal Tract - Lateral and Anterior Termination: Spinal Gray (Rexed IV-IX) Basal Portion Descending Tracts

Corticobulbar Tract

- Corticofugal fibers projecting to, and terminating in, portions of lower brainstem - Termination:1) motor nuclei (upper motor neuron pathway)hypoglossal, ambiguus, facial motor,trigeminal motor, abducens, trochlearand oculomotor nucleus2) sensory relay nucleinuclei gracilis and cuneatus, trigeminalsensory nucleus, solitary tract nucleus3) reticular formation (corticoreticular fiber) Basal Portion Descending Tracts

Basal Portion Descending TractsCorticobulbar Tract - UMN Pathway

- Corticofugal fibers projecting to cranial motor nuclei GSE - hypoglossal (XII), abducens (VI), trochlear (IV) and oculomotor (III) nucleus SVE -ambiguus (IX, X, XI), facial motor (VII),trigeminal motor (V) nucleus - largely bilateral laryngeal, pharyngeal, palatal and upper facial muscles of mastication and extraocular muscles - unilaterallower facial musculature (facial palsy) SCM and trapezius (uncrossed) --- spinal accessory - Pseudobulbar Palsy --- syndrome of bilateral UMN lesion

Basal Portion Descending Tracts Corticopontocerebellar Fiber

- Corticofugal fibers projecting to cerebellar hemisphere - consists of 2 neuron chain 1. Corticopontine fiber projecting to pontine nuclei 2. Pontocerebellar fiber crossed mudline and enter cerebellum as middle cerebellar peduncle

Roof PlateMidbrain Superior Colliculus: visionInferior Colliculus: hearingClosed MedullaNucleus Gracilis et Cuneatus: discriminative touch sensationcf. Cerebelum: equilibrium

Roof Plate of Hypothetized Chordate AncestorA. olfactionB. visionC. hearingD. equilibriumE. discriminative touch sensation

1. epithalamus2. superior colliculus3. inferior colliculus4. cerebellum5. nucleus gracilis et cuneatus

Tegmentum Cranial nerve Nuclei Precerebellar Nuclei Reticular Formation

Tracts Ascending Cortical Pathway Cerebellar Circuits Descending Tract Composite Bundle

Cranial Nerves Columns ofBrain Stem

Motor Column 1. GSE 2. SVE 3. GVE

Sensory Column 4. VA (GVA & SVA) 5. GSA 6. SSA

Components of Cranial Nerves

General Somatic Efferent Nuclei (GSE)Hypoglossal NucleusXIIAbducens NucleusVITrochlear NucleusIVOculomotor NucleusIII

Special Visceral Efferent Nuclei (SVE)Nucleus AmbiguusIX, X, XIFacial Motor NucleusVIITrigeminal Motor NucleusV

General Visceral Efferent Nuclei (GVE)Dorsal Motor Nucleus of VagusXInferior Salivatory NucleusIXSuperior Salivatory NucleusVIIEdinger-Westphal NucleusIII

Motor Nuclei ofCranial Nerves

1. GSE III, IV, VI, XII 2. SVE V, VII, IX, X, XI 3. GVE III, VII, IX, X

General Somatic Afferent Nuclei (GSA)Trigeminal Sensory Nucleus V, VII, IX, X Mesencephalic Tract Nucleus Principal (Main) Sensory Nucleus Spinal Tract Nucleus pars oralis pars interpolaris pars caudalis

Visceral Afferent Nuclei (VA)Nucleus Tractus Solitarius VII, IX, X General Visceral Afferent (GVA) Special Visceral Afferent (SVA): Taste Gustatory Nucleus

Special Somatic Afferent Nuclei (SSA)Cochlear Nucleus VIIIc Dorsal Cochlear Nucleus Ventral Cochlear NucleusVestibular Nucleus VIIIv Medial Vestibular Nucleus Lateral Vestibular Nucleus Superior Vestibular Nucleus Inferior Vestibular Nucleus

Sensory Nuclei ofCranial Nerves 1. VA GVA --- IX, X SVA --- VII, IX, X 2. GSA V, VII, IX, X

3. SSA VIIIc, VIIIv

Precerebellar NucleiAccessory Cuneate Nucleus Inferior Olivary Nuclear ComplexVestibular NuclusRed NucleusPerihypoglossal NucleusPrecerebellar Reticular Nuclei

PrecerebellarNuclei 1. Red Nucleus 2. Vestibular Nucleus

3. Inferior Olivary Nucleus4. Perhypoglossal Nuclei5. Accessory Cuneate Nucleus

Reticular Formation A. Raphe Nuclei B. Central Nuclear Group

C. Lateral Nuclear GroupD. Precerebellar Reticular NucleiABCD

Central Nuclear Group of Reticular FormationGigantocellular Reticular Nucleus Caudal Reticulopontine NucleusOral Reticulopontine NucleusSubcuneiform NucleusCuneiform Nucleus

Lateral Nuclear Group of Reticular FormationCentral Nucleus of Medulla OblongataSuperficial Ventrolateral Reticular AreaParvicellular Reticular NucleusParabrachial NucleusPedunculopontine Nucleus

Raphe Nuclei - Serotonergic NeuronNucleus Raphe Obscrus, B2Nucleus Raphe Pallidus, B1Nucleus Raphe Magnus, B3Pontine Raphe Nucleus, B5Median Raphe or Superior Central Nucleus, B6, B8Dorsal Raphe Nucleus, B7Nucleus Linealis

Norepinephrinergic & Dopaminergic NeuronNorepinephrinergic NeuronNucleus Locus Ceruleus, A6Dopaminergic NeuronRetrorubral Area, A8Ventral Tegmental Area, A10Substantia Nigra, Pars Compacta, A9

Ascending Cortical PathwayPosterior White Column-Medial Lemniscal Pathwaymedial lemniscusSpinothalamic and Spinoreticular Tractspinal lemniscusVentral and Dorsal Trigeminothalamic Tracttrigeminal lemniscusAuditory Pathway: lateral lemniscusTaste (Gustatory) Pathway: central tegmental tractVestibular Pathway: medial lemniscus

Ascending Cortical System General Sensation Brain Stem Pathways for General Sensation

Touch & Proprioception from body Posterior White Colum-Medial Lemniscal Pathway Pain & Temperature from body Spinothalamic Tract cf. Spinoreticular or Spinoreticulothalamic Tract General Sensation from Face Trigeminothalamic Tracts

Posterior White Column - medial Lemniscal Pathway& Spinothalamic Tract

Posterior White Colum-Medial Lemniscal Pathway Modality: Discriminative Touch Sensation (include Vibration) and Conscious Proprioception (Position Sensation, Kinesthesia) from body Receptor: Most receptors except free nerve endings

Ist Neuron: Dorsal Root Ganglion (Spinal Ganglion) Posterior White Column2nd Neuron: Dorsal Column Nuclei (Nucleus Gracilis et Cuneatus) Internal Arcuate Fiber - Lemniscal Decussation - Medial Lemniscus3rd Neuron: Thalamus (VPLc) Internal Capsule ----- Corona Radiata Termination: Primary Somesthetic Area (S I)

DRG: Dorsal Root Ganglion1. Posterior White ColumnA. Nucleus gracilisB. Nucleus cuneatus2. Medial Lemniscus3. Corona Radiata C. Thalamus (VPLc)D. Cerebral Cortex (S I)Posterior White Column-Medial Lemniscal Pathway DRGD

Spinothalamic Tract Modality: Pain & Temperature Sensation, Light Touch from body Receptor: Free Nerve Ending

Ist Neuron: Dorsal Root Ganglion (Spinal Ganglion) 2nd Neuron: Dorsal Horn (Lamina I, IV, V) Anterior White Commissure Spinothalamic Tract (Spinal Lemniscus) 3rd Neuron: Thalamus (VPLc & CL) Internal Capsule ----- Corona Radiata Termination: Primary Somesthetic Area (S I)

Spinoreticulothalamic Tract (Paleospinothalamic Tract) Modality: Pain & Temperature Sensation, Light Touch from body Receptor: Free Nerve Ending

Ist Neuron: Dorsal Root Ganglion (Spinal Ganglion) 2nd Neuron: Dorsal Horn (Lamina I, IV, V) Anterior White Commissure Spinothalamic Tract (Spinal Lemniscus) 3rd Neuron: Reticular Formation 4rd Neuron: Thalamus (CL, Sm, POm) Internal Capsule ----- Corona Radiata Termination: Diffuse Cerebral Cotex

DRG: Dorsal Root GanglionA. Posterior (dorsal) horn1. Spinothalamic tractB. Reticular formation2. Spinoreticular tractC. Thalamus (VPLc, CL)3. Corona Radiata D. Cerebral Cortex (S I)Spinothalamic Tract(Neospinothalamic Tract) Spinoreticular Tract(Paleospinothalamic Tract) DRGD

Trigeminothalamic Tract Modality: General Sensation from face Receptor: Most receptors in the face

Ist Neuron: Trigeminal (Semilunar) Ganglia 2nd Neuron: Trigeminal Sensory Nucleus pain & temperature ---- pars caudalis of spinal tract nucleus of V Ventral and Dorsal Trigeminothalamic Tract 3rd Neuron: Thalamus (VPM) Internal Capsule ----- Corona Radiata Termination: Primary Somesthetic Area (S I)

Trigeminothalamic TractA. trigeminal ganglionB. trigeminal sensory nucleusC. thalamus (VPM)D. cerebral cortex (S I)

1. spinal tract of trigeminal nerve2. ventral trigeminothalamic tract3. dorsal trigeminothalamic tract4. corona radiataV. trigeminal nerve

Ascending Cortical System Special Sensation Brain Stem Pathways for Special Sensation

Gustatory Sensation (Taste, SVA) ----- Taste Pathway Auditory Sensation (Hearing, SSA) ----- Auditory Pathway Vestibular Sensation (Equilibrium, SSA) ----- Vestibular Pathway

Auditory Pathway Modality: Auditory Sensation (Hearing) Receptor: Organ of Coti of Cochlear Duct Cranial Nerve: VIIIc

1st Neuron: Spiral Ganglion 2nd Neuron: Cochlear Nucleus, Ventral & Dorsal dorsal, intermediate and ventral acoustic striae trapezoid body lateral lemniscus 3rd Neuron: Inferior Colliculus brachium of inferior colliculus 4th Neuron: Medial Geniculate Nucleus (MG) auditory radiation Termination: Primary Auditory Area (A I) Brodmann area 31, 32

Auditory PathwaysA. spiral ganglionB. dorsal and ventral cochlear nucleusC. inferior colliculusD. medial geniculate nucleusE. Primary auditory areaF. superior olivary nucleusG. nucleus of lateral lemniscus

1. acoustic striae & trapezoid body2. lateral lemniscus3. brachium of inferior colliculus4. auditory radiation5. commissure of inferior colliculusVIIIc. cochlear division

Auditory PathwayA. spiral ganglionB. dorsal cochlear nucleusC. ventral cochlear nucleusD. superior olivary nucleus

1. dorsal acoustic striae2. intermediate acoustic striae3. ventral acoustic striae4. efferent cochlear bundle5. trapezoid body6. lateral lemniscus

Vestibular Pathway Modality: Equilibrium Sensation Receptor: Macula & Crista Ampullaris Cranial Nerve: VIIIv

Ist Neuron: Vestibular Ganglion 2nd Neuron: Vestibular Nucleus vestibulothalamic fiber (medial lemniscus) 3rd Neuron: Thalamus (VPLo, VPI?) Internal Capsule ----- Corona Radiata Termination: Primary Vestibular Area ----- Primary Somesthetic Area (Brodmann area 3a, 2v )

Vestibular Pathway 1. Vestibulocerebellar Tract 2. Vestibulospinal Tract

3. Vestibulothalamic Tract 4. Medial Longitudinal fasciculus (MLF) - ascending portion - descending portion - interstitiospinal tract

Taste (Gustatory) Pathway Modality: Taste Sensation Receptor: Taste Bud Cranial Nerve: VII, IX, X

Ist Neuron: Geniculate Ganglion (VII) Inferior Ganglion (IX, X) 2nd Neuron: Nucleus Tractus Solitarius (Gustatory Nucleus) solitariothalamic fiber (central tegmental tract) 3rd Neuron: Thalamus (VPMpc) Internal Capsule ----- Corona Radiata Termination: Gustatory Area Brodmann area 43 & parainsular cortex

Taste PathwaysA. nucleus tractus solitarius (gustatory nucleus)B. thalamus (VPMpc)C. Brodmann area 43D. parainsular cortexE. parabrachial nucleus

1. solitariothalamic fiber (central tegmental tract) 2. corona radiataVII. facial nerveIX. glossopharyngeal nerveX. vagus nerve

Cerebellar CircuitsSuperior, Middle and Inferior Cerebellar Peduncle

Vestibulocerebellum - Vestibular NucleusSpinocerebellum - Red Nucleus and Spinal CordPontocerebellum - Cerebral Cortex and Pontine Nuclei

Inferior Olivary Nuclear Complex

Afferent Connections of Cerebellum Inferior Cerebellar Peduncle 1. posterior spinocerebellar tract 2. cuneocerebellar tract 3. vestibulocerebellar tract Middle cerebellar Peduncle - corticopontocerebellar pathwaySuperior Cerebellar Peduncle - anterior spinocerebellar tract

Efferent Connections of Cerebellum Superior Cerebellar Peduncle 1. dentatothalamic fiber 2. interpositorubral fiber 3. ascending portion of uncinate fasciculus of Russell

Inferior Cerebellar Peduncle 1. direct fastigiovestibular fiber 2. descending portion of uncinate fasciculus of Russell

Connections of Inferior Olivary Nuclear Complex 1. Olivocerebellar Tract 2. Cortico-olivary Tract

3. Rubro-olivary Tract 4. Vestibulo-olivary Tract

5. Spino-olivary Tract

Descending TractsRubrospinal TractTectospinal tractVestibulospinal TractReticulospinal Tractpontine and medullaryDescending Autonomic Pathway

Brain Stem Descending Tracts Descending Tracts from Brain Stem

Dorsolateral (Motor) Pathway Rubrospinal Tract Ventromedial (Motor) Pathway Tectospinal Tract Vestibulospinal Tract MLF (Medial Longitudinal Fasciculus) - interstitiospinal tract Sensory Modulation pathways Raphespinal & Cerulospinal Pathways Descending Autonomic Pathways

Composite BundleMedial Longitudinal Fasciculus (MLF)Dorsal Longitudinal Fasciculus (DLF)Central Tegmental Tract

Components of Medial Longitudinal Fasciculus (MLF) Descending ComponentsMedial Vestibulospinal Tract from medial and inferior vestibular nucleusInterstitiospinal Tractfrom interstitial nucleus of Cajal Ascending Components Efferents from Medial Vestibular Nucleus contralateral III, IV, interstitial nucleus bilateral VI nucleusEfferents from Superior Vestibular Nucleus ipsilateral III, IV, interstitial nucleus

Ascending Componentssolitariohypothalamic fiber (visceral afferent fiber)ascending serotonergic fiber Descending Component descending fibers from hypothalamus to periaqueductal gray and dorsal tegmental nucleusComponents of Dorsal Longitudinal Fasciculus (DLF, fasciculus of Schtz)

Components of Central Tegmental Tract Ascending Componentsreticulothalamic fibersolitariothalamic fiber (secondary taste fiber) Descending Component rubro-olivary tract

Spinomedullary Transition (Level of Pyramidal Decussation) Roof Plate - fasciculus gracilis and fasciculus cuneatusTegmentum Cranial and Spinal Nerve NucleiSupraspinal NucleusSpinal Nucleus of Trigeminal Nerve, Pars Caudalis Reticular FormationCentral Nucleus of Medulla Oblongata (Ventral Reticular Nucleus) Unclassified NucleiRetroambiguus Nucleus TractsSpinal Tracts of Trigeminal NerveBasal Part - Pyramid, Pyramidal Decussation

Cranial & Spinal N. Nuclei1. Supraspinal Nucleus 2. Spinal Accessory Nucleus

Cranial & Spinal Nerve XI. Accessory NucleusC1. motor root of 1st cervical nerve

Spinomedullary Transition (Level of Pyramidal Decussation)

Lower Medulla (Level of Lemniscal Decussation)Roof Plate - nucleus gracilis and nucleus cuneatusTegmentum Cranial and Spinal Nerve NucleiHypoglossal Nucleus, Ambiguus NucleusSolitary Tract Nucleus, Dorsal Motor Nucleus of X Reticular FormationLateral Reticular Nucleus Precerebellar NucleiInferior Olivary Nuclear Complex TractsVentral Trigeminothalamic TractInternal Arcuate Fiber, Lemniscal DecussationBasal Part - Pyramid, Pyramidal Decussation

Lower Medulla(Level of LemniscalDecussation) Roof Plate A. Nucleus GracilisB. Nucleus CuneatusCranial Nerve Nuclei1. Hypoglossal Nucleus2. Nucleus Ambiguus3. Dorsal Motor Nucleus of X4. Nucleus Tractus Solitarius5. Spinal Tract Nucleus of Trigeminal Nerve

Lower Medulla(Level of LemniscalDecussation) Precerebellar Nucleus1. Inferior Olivary Nuclear Complex 1a. Principal Inferior Olivary Nucleus 1b. Medial Accessory Olivary Nucleus 1c. Dorsal Accessory Olivary Nucleus2. Nucleus Intercalatus3. Nucleus Conterminalis4. Arcuate Nucleus

Lower Medulla(Level of LemniscalDecussation) Reticular Formation 1. Lateral Reticular Nucleus2. Central Nucleus of Medulla Oblongata 2d. subnucleus dorsalis 2v. subnucleus ventralis

Clinical Syndromes of Lower Medulla A. Hypoglossal Alternating HemiplegiaB. Avelis SyndromeC. Jackson SyndromeD. Tapia Syndrome

1. pyramidal tract2. hypoglossal nerve 3. spinothalamic tract4. nucleus ambiguus

HypoglossalPalsy

Lower Motor NeuronSyndromeDeviation of Tongue to affected sideAtrophy of Tongue Muscles

Open Medulla (Mid-olivary Level) Tegmentum Cranial Nerve NucleiMedial Vestibular NucleusSpinal Tract Nucleus of V, pars interpolaris Precerebellar Nuclei Accessory Cuneate NucleusNucleus of Roller, Nucleus Interfascicularis Hypoglossi Reticular FormationLateral Reticular Nucleus, subtrigeminal portion Unclassified NucleiArea Postrema Tracts: Inferior Cerebellar Peduncle, DLFBasal Part - Pyramid

Cranial Nerve Nuclei1. Hypoglossal Nucleus2. Nucleus Ambiguus3. Dorsal Motor Nucleus of X4. Nucleus Tractus Solitarius5. Spinal Tract Nucleus, pars interpolaris6. Medial Vestibular NucleusOpen Medulla(Mid-olivary Level)

Open Medulla(Mid-olivary Level) Precerebellar Nucleus1. Accessory Cuneate Nucleus2. Inferior Olivary Nuclear Complex 2a. Principal Inferior Olivary Nuc. 2b. Medial Accessory Olivary Nuc. 2c. Dorsal Accessory Olivary Nuc. 3. Nucleus Intercalatus4. Nucleus of Roller5. Nucleus Interfascicularis Hypoglossi6. Nucleus Conterminalis

Open Medulla (Mid-olivary Level) XII. Hypoglossal Nerve1. Hypoglossal NucleusX. Vagus Nerve2. Nucleus Ambiguus3. Dorsal Motor Nucleus of X4. Nucleus Tractus Solitarius5. Spinal Tract Nucleus of V

A. Dejerines Syndrome1. pyramidal tract2. hypoglossal nerve 3. medial lemniscusB. Wallenberg Syndrome4. spinothalamic tract 5. spinal tract of trigeminal nerve6. nucleus ambiguus7. descending autonomic pathwayClinical Syndromes of Open Medulla

Wallenberg SyndromeSpinothalamic tract - contralateral loss of pain and temperature sensation at the bodySpinal tract of trigeminal nerve - ipsilateral loss of pain and temperature sensation at the face Nucleus ambiguus - dysphageia, dysarthria, hoarsenessDescending autonomic pathway - Horners syndrome (meiosis, ptosis, anhydrosis)

Open Medulla (Upper Level of Medulla) Tegmentum Cranial Nerve NucleiInferior Vestibular NucleusDorsal Cochlear Nucleus Precerebellar Nuclei Nucleus Prepositus Hypoglossi Reticular FormationGigantocellular Reticular NucleusParagigantocellular Reticular NucleusParvocellular Reticular NucleusRaphe Nuclei Unclassified Nucleiretrofacial, supravestibular nucleus, nucleus interpositus Tracts: stria medullaris of 4th ventricleBasal Part - Pyramid

Cranial Nerve Nuclei1. Nucleus Ambiguus2. Nucleus Tractus Solitarius3. Spinal Tract Nucleus, pars oralis4. Medial Vestibular Nucleus5. Inferior Vestibular Nucleus6. Dorsal Cochlear NucleusOpen Medulla(Upper Level of Medulla)

Open Medulla(Upper Level of Medulla) Precerebellar Nucleus1. Inferior Olivary Nuclear Complex 2a. Principal Inferior Olivary Nuc. 2b. Medial Accessory Olivary Nuc. 2c. Dorsal Accessory Olivary Nuc. 2. Nucleus Prepositus Hypoglossi3. Pontobulbar Body4. Arcuate Nucleus5. Medial Vestibular Nucleus6. Inferior Vestibular Nucleus

Open Medulla(Upper Level of Medulla) Reticular Formation 1. Paramedian reticular Nucleus2. Gigantocellular Reticular Nucleus3. paragigantocellular Reticular Nucleus4. Parvocellular Reticular Nucleus5. Nucleus raphe Obscrus (B2)6. Nucleus Raphe Pallidus (B1)7. Nucleus Raphe Magnus (B3)Unclassifiied NucleiA. Nucleus RetrofacialisB. Supravestibular NucleusC. Nucleus Interpositus

IX. glossopharyngeal Nerve1. Nucleus Ambiguus2. Inferior Salivatory Nucleus3. Nucleus Tractus Solitarius4. Spinal Tract Nucleus of VOpen Medulla (Upper Level of Medulla)

Pontomedullary Junction Tegmentum Cranial Nerve NucleiFacial Motor NucleusVentral Cochlear Nucleus Precerebellar Nuclei Reticular Formation Unclassified Nucleinucleus ovalis TractsBasal Part - PyramidCranial Nerve - Vestibulocochlear Nerve (VIII) Facial Nerve (VII)

Cranial Nerve Nuclei

1. Facial Motor Nucleus 2. Nucleus Ambiguus3. Spinal Tract Nucleus, pars oralis4. Medial Vestibular Nucleus5. Inferior Vestibular Nucleus6. Ventral Cochlear NucleusPontomedullaryJunction

PontomedullaryJunctionPrecerebellar Nucleus1. Principal Inferior Olivary Nucleus2. Nucleus Prepositus Hypoglossi3. Pontobulbar Body4. Arcuate Nucleus5. Medial Vestibular Nucleus6. Inferior Vestibular Nucleus

PontomedullaryJunctionReticular Formation 1. Paramedian reticular Nucleus2. Gigantocellular Reticular Nucleus3. paragigantocellular Reticular Nucleus4. Parvocellular Reticular Nucleus7. Nucleus Raphe Magnus (B3)Unclassifiied NucleiA. Nucleus InterpositusB. Nucleus Ovalis

Lower Pons (Level of Abducens Nucleus) Tegmentum Cranial Nerve NucleiAbducens Nucleus, Main Sensory Nucleus of V Nuclei of Auditory PathwaySuperior Olivary Nuclear Complex Reticular FormationCaudal Pontine Reticular & Subceruleus Nucleus TractsTrapezoid Body, lateral Lemniscus, Central tegmental Tract Basal Part: Pons Proper: Pontine Nuclei,Transverse Pontine Fiber, Longitudinal Pontine Fiber (Pyramidal Tract)

Lower Pons (Level of Abducens Nucleus) Cranial Nerve Nuclei1. Abducens Nucleus2. Main Sensory Nucleus of V3. Lateral vestibular Nucleus4. Superior Vestibular NucleusAuditory Relay Nuclei A. Superior Olivary NucleusB. Nucleus of Trapezoid body

Lower Pons (Level of Abducens Nucleus) Reticular Formation 1. Gigantocellular Reticular Nucleus 2. Caudal Pontine Reticular Nucleus 3. Parvocellular Reticular Nucleus 4. Nucleus Subceruleus

VII. Facial Nerve 1. Facial Motor Nucleus 2. Superior Salivatory Nucleus 3. Nucleus Tractus Solitarius 4. Spinal Tract Nucleus of VVI. Abducens Nerve 5. Abducens Nucleus

A. Facial PalsyB. A + decreased salivationC. A + B + hyperacusisD. A + B + C + decrased lacrimal secretionE. Central Type Facial Palsy1. Facial Motor Nucleus2. Superior Salivatory Nucleus3. Solitary Nucleus4. Spinal Tract Nucleus of Trigeminal Nerve

Facial Palsy(Bells Palsy)

Lower MotorNeuronSyndromeTriple W Sign - Wrinkle, Wink, Whistle

Right facial paralysisFacial Palsy (Bells Palsy)

Central TypeFacial Palsy

Upper MotorNeuronSyndromefacial motor nucleus neuronssupplying forehead muscleBilateral Corticobulbar Tract

AbducensPalsy

Lower Motor NeuronSyndromeLateral Gaze Paralysis

Upper Pons (Level of Trigeminal Motor Nucleus) Tegmentum Cranial Nerve NucleiTrigeminal Motor Nucleus,Mesencephalic Tract Nucleus of Trigeminal Nerve Nuclei of Auditory PathwayNucleus of Lateral Lemniscus Reticular FormationReticular Tegmental Nucleus Unclassified NucleusPontine Central Gray: Ch6 TractsTrigeminal Nerve Fiber Basal Part: Pons Proper

Upper Pons (Level of Trigeminal Motor Nucleus)Cranial Nerve Nuclei1. Trigeminal Motor Nucleus2. Main Sensory Nucleus of V3. Mesencephalic Tract Nucleus of V4. Superior Vestibular NucleusAuditory Relay Nuclei A. Nucleus of Lateral Lemniscus

Upper Pons (Level of Trigeminal Motor Nucleus)Reticular Formation 1. Caudal Pontine Reticular Nucleus 2. Nucleus Subceruleus 3. Reticular Tegemntal Nucleus of Bekhterew (Nucleus Papilloformis of Olszewski and Baxter)

A. Millard-Gubler SyndromeB. Raymond SyndromeC. Foville SyndromeD. Raymond-Cestan SyndromeE. Marie-Poix Syndrome

1. pyramidal tract2. MLF3. medial lemniscus4. spinothalamic tract5. trigeminal motor nucleus6. main sensory nucleus of V7. spinal tract of trigeminal nerve8. middle cerebellar peduncle Clinical Syndromes of Pons

Trigeminal Neuralgia(tic douloureux)- excruciating episodic pain in the area supplied by trigeminal nerve, especially second and third division- trigger point- intense pain makes the patient grimace (tic)- antiepileptic drug (phenytoin, carbamazepine) is effective- surgical treatment

Lower Midbrain (Level of Inferior Colliculus) Roof Plate - Tectum: Inferior ColliculusTegmentum Cranial Nerve NucleiTrochlear Nucleus Reticular FormationCuneiform, Pedunculopontine, Parabrachial and Median Raphe (Superior Central) Nucleus Unclassified NucleiPeriaqueductal Gray TractsDecussation of Superior Cerebellar PeduncleBasal Part - Crus Cerebri, Pons Proper

Lower Midbrain (Level of Inferior Colliculus) Roof Plate A. Inferior Colliculus

Cranial Nerve Nuclei1. Mesencephalic Tract Nucleus of Trigeminal Nerve2. Trochlear Nucleus

Lower Midbrain (Level of Inferior Colliculus) Reticular Formation 1. Cuneiform Nucleus2. Pedunculopontine Nucleus3. Nucleus Locus ceruleus4. Parabrachial Nucleus5. Dorsal Raphe Nucleus6. Median Raphe Nucleus

Unclassified NucleiA. Periaqueductal GrayB. Dorsal Tegmental Nucleus of GuddenC. Interpeduncular NucleusD. Parabigeminal NucleusC65

Upper Midbrain (Level of Superior Colliculus) Roof Plate - Tectum: Superior ColliculusTegmentum Cranial Nerve NucleiOculomotor and Edinger-Westphal Nucleus Reticular Formation - Subcuneiform Nucleus Precerebellar Nuclei Red Nucleus Unclassified NucleiSubstantia Nigra, Paranigral, Paralemniscal NucleusVentral Tegmental Area (VTA) TractsBrachium of Inferior ColliculusBasal Part - Crus Cerebri

Upper Midbrain (Level of Superior Colliculus) Roof Plate A. Superior ColliculusPrecerebellar NucleusB. Red Nucleus

Cranial Nerve Nuclei1. Mesencephalic Tract Nucleus of V2. Oculomotor Nucleus3. Edinger-Westphal Nucleus

Upper Midbrain (Level of Superior Colliculus) Reticular Formation A. Cuneiform NucleusB. Subcuneiform NucleusUnclassified Nuclei1. Periaqueductal Gray2. Paralemniscal Nucleus 3. Substantia Nigra 3a. Pars Compacta 3b. Pars Reticulata4. Paranigral Nucleus5. Ventral Tegmental Area

Clinical Syndromes of Upper Midbrain A. Weber SyndromeB. Foix SyndromeC. Benedikts SyndromeD. Claude SyndromeE. Parinauds Syndrome

1. pyramidal tract2. superior cerebellar peduncle 3. red nucleus4. medial lemniscus5. superior colliculus6. cerebral aqueduct7. MLF8. oculomotor nucleus

Weber SyndromePyramidal tract - contralateral UMN syndrome at the body and lower face (contralateral hemiparesis) Oculomotor Nerve - ipsilateral ocular palsy - external strabismus - mydriasis - loss of accommodation - normal consensual light reflex

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