Cranial Nerves Overview PDF

Overview of Relevant Anatomy  Primary Areas Oral cavity Pharyngeal cavity Larynx Esophagus Oral Cavity Pharyngeal Cavity Larynx Esophagus  Cranial Nerves Special...

Overview of Relevant Anatomy  Primary Areas Oral cavity Pharyngeal cavity Larynx Esophagus Oral Cavity Pharyngeal Cavity Larynx Esophagus  Cranial Nerves Special Cranial Nerve Motor Sensory Nuclei Location Sensory V – trigeminal Muscles of mastication Face Midbrain, pons, Some suprahyoids Mouth medulla oblongata Teeth Anterior tongue Hard/soft palate VII – facial Muscles of face Taste Pons Some suprahyoids anterior 2/3 tongue IX – glossopharyngeal Stylopharyngeus Posterior tongue Taste Medulla oblongata Soft palate posterior Pharynx 1/3 tongue X – vagus Soft palate Soft palate Taste Medulla oblongata Pharynx Pharynx epiglottis Larynx Larynx Cricopharyngeus Esophagus XI – spinal accessory Assists vagus with muscles of Upper spinal cord velum Head and shoulder movement XII – hypoglossal Intrinsic and extrinsic tongue Medulla oblongata muscles Hyoglossus  Cranial Nerves 1. Olfactory 2. Optic 3. Oculomotor 4. Trochlear 5. Trigeminal 6. Abducens 7. Facial 8. Acoustic 9. Glossopharyngeal 10. Vagus 11. Accessory 12. Hypoglossal  Harry Potter and the Cranial Nerves On, on, on they traveled I – olfactory, II – optic, III – oculomotor, IV – trochlear, V – trigeminal And found Voldemort VI – abducens, VII – facial, VIII – vestibulocochlear Guarding very ancient horcruxes IX – glossopharyngeal, X – vagus, XI – accessory, XII – hypoglossal END Oral Cavity Anatomy  Primary Areas Oral cavity Pharyngeal cavity Larynx Esophagus Oral Oral Lips Teeth/ gums  Oral Lateral sulci Anterior sulcus  Salivary Glands Parotid gland Sublingual gland Submandibular gland  Cranial Nerves Special Cranial Nerve Motor Sensory Nuclei Location Sensory V – trigeminal Muscles of mastication Face Midbrain, pons, medulla Some suprahyoids Mouth oblongata Teeth Anterior tongue Hard/soft palate VII – facial Muscles of face Taste Pons Some suprahyoids anterior 2/3 tongue IX – glossopharyngeal Stylopharyngeus Posterior tongue Taste Medulla oblongata Soft palate posterior 1/3 Pharynx tongue X – vagus Soft palate Soft palate Taste Medulla oblongata Pharynx Pharynx epiglottis Larynx Larynx Cricopharyngeus Esophagus XI – spinal accessory Assists vagus with muscles of velum Upper spinal cord Head and shoulder movement XII – hypoglossal Intrinsic and extrinsic tongue muscles Medulla oblongata Hyoglossus END Trigeminal Nerve  V – Trigeminal Special Cranial Nerve Motor Sensory Nuclei Location Sensory V – trigeminal Muscles of mastication Face Midbrain, pons, Some suprahyoids Mouth medulla oblongata Teeth Anterior tongue Hard/soft palate V – Trigeminal: Motor Function Temporalis Temporomandibular joint Pterygoid muscle Masseter  V – Trigeminal: Motor Function Muscle Origin Insertion Nerve Action Temporalis Temporal fossa of Ramus and Trigeminal Elevates or closes skull coronoid process mandible; retracts of mandible mandible Masseter Zygomatic arch Ramus of Trigeminal Elevates or closes mandible mandible Medial Palatine bone, Ramus of Trigeminal Elevates or closes pterygoid lateral pterygoid mandible mandible plate, tuberosity of maxilla Lateral Great wing of Neck of condyle Trigeminal Depressor or opener pterygoid sphenoid and of mandible of mandible; lateral pterygoid protrudes mandible; plate permits side to side movement of mandible  V – Trigeminal: Sensory Function Ophthalmic branch Maxillary branch Mandibular branch  V – Trigeminal: Impacts of Injury? Cranial Special Nuclei Motor Sensory Nerve Sensory Location V – trigeminal Muscles of Face Midbrain, pons, mastication Mouth medulla Some suprahyoids Teeth oblongata Anterior tongue Hard/soft palate END Facial Nerve  VII – Facial Cranial Special Nuclei Motor Sensory Nerve Sensory Location VII – facial Muscles of face Taste anterior Pons Some suprahyoids 2/3 tongue VII – Facial: Motor Function VII – Facial: Motor Function  VII – Facial: Motor Function Muscle Origin Insertion Nerve Action Orbicularis oris Neighboring muscles, Skin around lips Facial Closes, opens, protrudes, mostly buccinators; has and angles of the inverts, and twists lips many layers of tissue mouth around the lips Zygomaticus minor Zygomatic bone Orbicularis oris in Facial Draws upper lip upward and upper lip outward Levator labii superior Below infraorbital Orbicularis in Facial Pulls up or elevates foramen in maxilla upper lip upper lip Levator labii superior Process of maxilla Skin at mouth Facial Raises angle of the mouth angle, orbicularis oris Zygomaticus major Zygomatic bone Fibers of the Facial Draws upper lip upward; draws orbicularis oris, angle of mouth upward and angle of the mouth backward; the smiling muscle  VII – Facial: Motor Function Muscle Origin Insertion Nerve Action Levator anguli oris Canine fossa of maxilla Lower lip near Facial Pulls down corners of mouth angle of the mouth Depressor anguli oris Outer surface and above Skin of cheek, Facial Draws lower lip down; draws lower border of mandible corner of mouth, angle of mouth down and lower border of inward mandible Depressor labii Lower border of the Skin of lower lip, Facial Depresses lower lip inferior mandible orbicularis oris Mentalis Incisor fossa of mandible Skin of chin Facial Pushes lower lip; raises chin Risorius Platysma, facia over the Angle of mouth, Facial Draws corners or angle of masseter skin orbicularis oris mouth outward; causes dimples; gives expression of strain to face Buccinator Alveolar process of Angle of mouth, Facial Flattens cheek; holds food in maxilla, buccinators ridge orbicularis oris contact with teeth; retracts of mandible angles of the mouth Levator anguli oris Canine fossa of maxilla Lower lip near Facial Pulls down corners of mouth angle of the mouth VII – Facial: Sensory Function IX innervation VII innervation  VII – Facial: Impacts of Injury? Special Cranial Nerve Motor Sensory Nuclei Location Sensory VII – facial Muscles of face Taste Pons Some suprahyoids anterior 2/3 tongue END Hypoglossal Nerve  XII – Hypoglossal Special Cranial Nerve Motor Sensory Nuclei Location Sensory XII – hypoglossal Intrinsic and extrinsic tongue muscles Medulla oblongata Hyoglossus XII – Hypoglossal: Motor Function Extrinsic Intrinsic  XII – Hypoglossal: Motor Function Extrinsic Muscle Nerve Action Hyoglossus Hypoglossal Retracts, depresses, elevates Genioglossus Hypoglossal Protrudes tip, retracts, depresses Styloglossus Hypoglossal Draws up and back Intrinsic Muscle Nerve Action Superior longitudinal Hypoglossal Shortens, turns tip and lateral margins upward Inferior longitudinal Hypoglossal Shortens, pulls tip downward Transverse Hypoglossal Narrows, elongates Vertical Hypoglossal Flattens, widens  XII – Hypoglossal: Impacts of Injury? Special Cranial Nerve Motor Sensory Nuclei Location Sensory XII – hypoglossal Intrinsic and extrinsic tongue muscles Medulla oblongata Hyoglossus END Pharyngeal/Laryngeal Anatomy Hyoid Bone  Hyoid Bone Motor innervation to attached muscles: CN V, VII, XII Cervical plexus Ansa cervicalis  Primary Areas Oral cavity Pharyngeal cavity Larynx Esophagus Pharynx and Larynx The Pharynx  Pharynx and Larynx Important structures Hyoid bone Velum Epiglottis Laryngeal vestibule False vocal folds True vocal folds Valleculae Pyriform sinuses Pharyngoesophageal segment  Pharynx and Larynx Important structures Hyoid bone Velum Epiglottis Laryngeal vestibule False vocal folds True vocal folds Valleculae Pyriform sinuses Pharyngoesophageal segment  Pharynx and Larynx Important structures Hyoid bone Velum Epiglottis Laryngeal vestibule False vocal folds True vocal folds Valleculae Piriform sinuses Pharyngoesophageal segment Pharynx and Larynx 1. Vocal folds 5. Arytenoid 2. False 6. Piriform vocal folds sinuses 3. Epiglottis 7. Tongue base 4. Aryepiglottic fold Pharynx and Larynx  Cranial Nerves Special Cranial Nerve Motor Sensory Nuclei Location Sensory V – trigeminal Muscles of mastication Face Midbrain, pons, medulla Some suprahyoids Mouth oblongata Teeth Anterior tongue Hard/soft palate VII – facial Muscles of face Taste Pons Some suprahyoids anterior 2/3 tongue IX – glossopharyngeal Stylopharyngeus Posterior tongue Taste Medulla oblongata Soft palate posterior Pharynx 1/3 tongue X – vagus Soft palate Soft palate Taste Medulla oblongata Pharynx Pharynx epiglottis Larynx Larynx Cricopharyngeus Esophagus XI – spinal accessory Assists vagus with muscles of velum Upper spinal cord Head and shoulder movement XII – hypoglossal Intrinsic and extrinsic tongue muscles Medulla oblongata Hyoglossus Labeling the Oropharyngeal Anatomy Pharynx and Larynx  Pharynx and Larynx Hyoid Mandible Base of tongue Epiglottis Valleculae Vocal folds Laryngeal vestibule Velum Spine Pyriform sinuses PES Upper esophagus Glossopharyngeal Nerve  IX – Glossopharyngeal Special Cranial Nerve Motor Sensory Nuclei Location Sensory IX – Stylopharyngeus Posterior tongue Taste Medulla oblongata glossopharyngeal Soft palate posterior 1/3 Pharynx tongue IX – Glossopharyngeal: Motor Function Stylopharyngeus Elevates pharynx Contributes to laryngeal elevation  IX – Glossopharyngeal: Sensory Function Sensory Special sensory IX innervation VII innervation  IX – Glossopharyngeal: Impacts of Injury? Special Cranial Nerve Motor Sensory Nuclei Location Sensory IX – Stylopharyngeus Posterior Taste Medulla oblongata glossopharyngeal tongue Soft posterior palate Pharynx 1/3 tongue END Vagus Nerve X – Vagus  X – Vagus Special Cranial Nerve Motor Sensory Nuclei Location Sensory X – vagus Soft palate Soft palate Taste Medulla oblongata Pharynx Pharynx epiglottis Larynx Larynx Cricopharyngeus Esophagus X – Vagus: Motor Function Velum  X – Vagus: Motor Function Velum Muscle Origin Insertion Nerve Action Levator veli Apex of Palatine Vagus and Raises of soft palate palatini temporal aponeurosis accessory bone of soft palate Tensor veli palatini Fossa of Palatine Trigeminal Stretches soft palate sphenoid aponeurosis bone of soft palate Palatoglossus Undersurface Side of Vagus and Raises back of tongue of soft palate tongue accessory during the first stage of swallowing Palatopharyngeus Soft palate Pharyngeal Vagus and Depresses soft palate, wall accessory guides bolus into lower pharynx Uvulae Posterior Into uvula to Vagus and Shortens and raises nasal spine form its accessory uvula and palatine chief bulk or aponeurosis content X – Vagus: Motor Function Pharynx Superior constrictor Middle constrictor Inferior constrictor Thyropharyngeus Cricopharyngeus X – Vagus: Motor Function Pharynx Muscle Nerve Action Superior constrictor Vagus Contracts on bolus to squeeze down Middle constrictor Vagus Contracts on bolus to squeeze down Inferior constrictor Vagus Relaxes to allow bolus to pass (includes thyropharyngeus and cricopharyngeus) Palatopharyngeus Vagus Elevates pharynx, contracts on bolus, some laryngeal elevation Salpingopharyngeus Vagus Elevates pharynx and laterally draws walls up Stylopharyngeus Accessory Elevates pharynx, some laryngeal elevation  X – Vagus: Motor Function Larynx Intrinsic muscles Action of intrinsic of larynx (posterior view) muscles of larynx  X – Vagus: Motor Function Larynx Muscle Nerve Action Thyroarytenoid (includes Vagus Adducts, tenses, or vocalis) relaxes VFs Cricothyroid Vagus Lengthens and tenses VFs Posterior cricoarytenoid Vagus Abducts VFs and externally rotates arytenoids Lateral cricoarytenoid Vagus Adducts VFs and internally rotates arytenoids Transverse arytenoid Vagus Adducts arytenoids Oblique arytenoid Vagus Adducts arytenoids  X – Vagus: Motor Function, Pharyngoesophageal Segment Inferior Hyoid Hyoid pharyngeal bone bone constrictor muscle Thyroid Inferior cartilage pharyngeal Cricopharyngeus constrictor Thyroid muscle Cricoid cartilage UES: CP and cartilage upper esophagus Cricoid Circular Trachea cartilage Esophagus muscle layer of esophagus Trachea Esophagus PES: pharyngoesophageal segment UES: upper esophageal sphincter CP: cricopharyngeus X – Vagus: Sensory Function X – Vagus: Special Sensory Function  X – Vagus: Results of Injury? Special Cranial Nerve Motor Sensory Nuclei Location Sensory X – vagus Soft palate Soft palate Taste Medulla oblongata Pharynx Pharynx epiglottis Larynx Larynx Cricopharyngeus Esophagus END Spinal Accessory Nerve  XI – Spinal Accessory Special Cranial Nerve Motor Sensory Nuclei Location Sensory XI – spinal accessory Assists vagus with muscles of velum Upper spinal cord Head and shoulder movement XI – Spinal Accessory: Motor Function XI – Spinal Accessory: Motor Function  XI – Spinal Accessory: Results of Injury? Special Cranial Nerve Motor Sensory Nuclei Location Sensory XI – spinal accessory Assists vagus with muscles of velum Upper spinal cord Head and shoulder movement END Esophagus  Primary Areas Oral cavity Pharyngeal cavity Larynx Esophagus  Esophagus Striated Striated smooth Smooth 21–27 cm C6 Collapsed at rest, distends up to three cm  Esophagus Esophagus Diaphragmatic hiatus  Gastrointestinal System Functions Esophagus: transports food to digestive system Stomach: breaks down proteins Duodenum: breaks down fats, carbohydrates Jejunum: absorbs carbohydrates and proteins Ileum: absorbs fats Colon: transports waste, absorbs water Healthy Bacteria in the GI Tract Normal colonization in gastric system, oral/pharyngeal cavity Reduced colonization with oral care Increased colonization with antibiotics, oral disease, xerostomia, malnutrition, acid suppression END Respiratory System  Respiration and Deglutition Upper aerodigestive tract is shared Ventilation stops with swallowing (apnea)  Respiration and Deglutition Upper aerodigestive tract is shared Ventilation stops with swallowing (apnea) In normal: Exhalation à swallow à exhalation most common Other patterns possible Risks? END Neural Control of Swallowing  Neural Control of Swallowing Three types of neurons: 1. Sensory 2. Motor 3. Interneurons Central pattern generator(s) CPG sets up the sequence for basic function Also inhibits other functions of those nerves during a swallow Neural Control of Swallowing  Neural Control of Swallowing: A Reflex?  Neural control Muscle function Kinematics Performance Sensory feedback END