SLHS 261 1st Edition Lecture 9 Outline of Last Lecture I. ExamOutline of Current Lecture II. Neural Control of BreathingA. Brainstem sends information to:i. diaphragm via spinal nerves C3-C5ii. external intercostals (stiffen rib cage and assist diaphragm) iii. Laryngeal and upper airways to increase sizeB. Brainstem complex in medulla help to control respiratory rhythm. Glutamate and GABA help regulate respiratory breathing. Brainstem injury results in decreased breathing and vital capacity. C. Cranial Nerves for larynx and upper airwaysIX- glossopharyngealX- VagusXII- hypoglossalXI- accessory (sternocleidomastoid)III. Laryngeal AnatomyA. Definitionsi. Facet- small area on structure where it contacts another structure. ii. Articulation- a joint or juncture of bones or cartilagesB. Larynx i. Cartilaginous tube that connects the vocal tract to the esophagusii. Primary function- protect the airwayThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.iii. Secondary function- provide the sound source for speech (vocal fold)C. Structural Support for the Larynx i. 1 bone (hyoid); 6 cartilages: thyroid, cricoid, arytenoid, epiglottis, corniculate, cuneiformii. Hyoid bone- comes in contact with the thyroid cartilage and serves as the attachment for several laryngeal musclesiii. Thyroid Cartilage- Protects the laryngeal structures. Two lamina attach at anterior midline and form the “Adam’s apple”. The superior cornua articulates with the hyoid bone and the interior cornua articulates with the cricoid cartilage. iv. The Cricoid Cartilage: Facets articulate with the inferior cornua of the thyroid cartilage and the arytenoid cartilages. Cricoid Cartilage is connected to thefirst tracheal ring via the laryngeal membrane. This cartilage makes up the inferiorborder of the laryngeal complex. v. Arytenoid Cartilages: a. Apex- capped with corniculate cartilageb. Anterior side- vocal process; attaches to vocal folds c. Lateral side- muscular process; attaches to muscles for ad/abductiond. Medial side- even surface for midlineglottis closure e. Base- concave cylinder that articulate smoothly with convex superior surface of posterior cricoid cartilage vi. Epiglottis (shoehorn or leaf-shaped): Attaches to the hyoid bone and allows for retroversion of the epiglottis for airway closure. IV. Laryngeal JointsA. Cricothyroid: 2 facets and 3 ceratocricoid ligamentsThe thyroid and cricoid cartilages can rotate. This is important for pitch control.B. Cricoarytenoid joint: Rock on the cricoid and aid the vocal processes in moving upward and outward or downward and inward. V. Intrinsic Laryngeal Ligaments and MembraneA. Conus elasticus- membrane that connects cricoid, arytenoid, and thyroid cartilagesB. Middle cricothyroid ligament- limits S/I and A/P separation of cricoid and thyroid cartilagesC. Lateral cricothyroid membranes- limits A/P separation of cricoidand thyroid cartilagesD. Vocal ligaments- limit A/P separation of thyroid and arytenoid cartilagesVI. Extrinsic Laryngeal Ligaments and MembranesA. Cricotracheal membrane- limits S/I separation of cricoid and tracheaB. Hyoepiglottic ligament- limits A/P separation of hyoid and epiglottis C. Hyothyroid membrane and ligaments- limits S/I separation of hyoid and thyroid