Phonation Anatomy & Physiology PDF

~BASIC TERMINOLOGY~ *Respiration is the source of energy (essential) for speech/phonation PHONATION- production of vocalization or “voice” *due to cyclic opening + closing of vocal folds result of pressure (aerodynamics + muscle tension) *Vocal folds (VF)...

~BASIC TERMINOLOGY~ *Respiration is the source of energy (essential) for speech/phonation PHONATION- production of vocalization or “voice” *due to cyclic opening + closing of vocal folds result of pressure (aerodynamics + muscle tension) *Vocal folds (VF) are the primary muscles of phonation LARYNX- funnel shaped arrangement of cartilage, connective tissue + muscle Primary Function: PROTECTION Secondary Function: VOICE/PHONATION 1. COUGHING Effect of Non-speech laryngeal functions: Deep inhale → VF open 1. POSITIVE Elevate larynx Used to open VF Tense + tight → VF close *for client who cannot open VF → coughing Subglottal pressure blow VF apart or abdominal fixation can be clinical *repeated can cause damage technique to initiate phonation 2. THROAT CLEARING 2. NEGATIVE Same as coughing Used to close VF *Less force BUT can still cause damage *can cause damage 3. ABDOMINAL FIXATION Large inhale → VF open Tight closure → VF close ex: lifting weights, childbirth, defecation 4. REFLEXIVE ACTIONS Involuntary opening of VF occurs in preparation for a breath ~MYOELASTIC-AERODYNAMIC THEORY OF PHONATION~ VF opening + MYOELASTIC PHASE- elasticity of VF allow them to close closing causes SUBGLOTTAL AIR PRESSURE (3-5 cm H20) - builds below larynx + blows VF apart vibration → AERODYNAMIC PHASE- pressure velocity of air (Bernoulli Effect) VOICE! c, 2022 Klaudia’s SLP Packets  ~STRUCTURES OF PHONATION~ VOCAL FOLDS/CORDS “TRUE VF”- run from arytenoid cartilage to thyroid cartilage; major movement VENTRICULAR FOLDS “FALSE VF”- minor movement FRONT GLOTTIS- space between VF (natural) ABDUCTION (open)- VF open from back to front *think, you want your abs to stick out (ABD) ADDUCTION (close)- VF close from front to back *ADD = adds together at midline BACK Both are caused by muscular action LARYNGEAL CARTILAGES: CARTILAGES PAIRED CARTILAGES 1. CRICOID 1. ARYTENOID most inferior of larynx + made of hyaline small + pyramid-shaped cartilages cartilage 2. CORNICULATE 2. THYROID small cartilages located on arytenoids largest + made of hyaline cartilage (two 3. CUNEIFORM fused plates) small cartilages within aryepiglottic folds 3. EPIGLOTTIS leaf-like elastic cartilage + protective CARTILAGE JOINTS: 1. CRICOTHYROID- cricoid + thyroid located on articular facets Synovial joint- rocking movement Hyoid bone Epiglottis Controls pitch- changes VF length + tension 2. CRICOARYTENOID- cricoid + arytenoid Cuneiform *attached separately BUT move in harmony cartilage Synovial joint- *changes glottis* Ventricular Corniculate folds Rocking- ADD → rock in + down cartilage Thyroid ABD → rock up + out Arytenoid cartilage cartilage Gliding- ADD → glide down + medial ABD → glide up + lateral Vocal folds Cricoid Rotation- slight movement @ extreme ABD cartilage Tracheal cartilages HYOID BONE- NOT bone of larynx → larynx is suspended from hyoid Functions: 1. Attachment LARYNX 2. Supports the tongue + larynx (sagittal view) c, 2022 Klaudia’s SLP Packets CAVITIES: VALLECULAE- (2) between tongue + epiglottis PYRIFORM SINUSES- (2) between aryepiglottic folds + thyroid cartilage Thyroid cartilage LARYNGEAL CAVITY- I I. VESTIBULAR/SUPERIOR DIVISION II Aditus Laryngis- cavity opening Glottis Protected by aryepiglottic folds II. VENTRICULAR/ MIDDLE DIVISION III Cricoid cartilage contains VF III. INFRAGLOTTIC/ SUBGLOTTIC DIVISION Bernoulli Effect MEMBRANES + LIGAMENTS: Membranes- Epithelial tissue (mucus) Ligaments- Fibrous connective tissue (bones to cartilages) *characterized by location → extrinsic + intrinsic 1. EXTRINSIC MEMBRANES + LIGAMENTS THYROHYOID- thyroid + hyoid - attach larynx to outer structures CRICOTRACHEAL- cricoid + trachea *provides stability for larynx HYOEPIGLOTTIC- hyoid + epiglottis 2. INTRINSIC MEMBRANES + LIGAMENTS THYROEPIGLOTTIC- thyroid + epiglottis - stays within larynx CRICOTHYROID- cricoid + thyroid *supports larynx + vocal folds *connects cartilages 3. CONUS ELASTICUS (CRICOVOCAL MEMBRANE TRUE VF 4. QUADRANGULAR MEMBRANE FALSE VF VOCAL FOLD LAYERS: GLOTTAL/PHONATORY SOURCE → voice is 1. SQUAMOUS EPITHELIUM with maintained by: basement membrane VF remain closed 2. SUPERFICIAL Subglottal pressure 3-5 cmH2O for normal Lamina propria 3. INTERMEDIATE speech 4. DEEP Airflow 5. MUSCLE *Maximum phonation time- average 10 seconds *3-4 make up the vocal ligament *Termination of phonation- VF abduct (caused by posterior cricoarytenoid) GLOTTAL CYCLE- closed + open phases VOICING ONSET- initiation of phonation ( + Bernoulli Effect) VIBRATORY CYCLE OF VOCAL FOLDS- “VERTICAL PHASE DIFFERENCE” Open → back to front (tongue) Properties of VF vibration: Close → front (tongue) to back Elasticity/Myoelasticity *vibrations of VF is product of airflow interaction with Stiffness- elastic strength of VF VF tissue in the absence of repetitive muscular contraction Inertia- mass or quantity of c, 2022 Klaudia’s SLP Packets matter of VF  LARYNGEAL MUSCLES: EXTRINSIC- connect inside larynx to outside (ex: hyoid, sternum, tongue, etc) Function: Elevate OR Depress hyoid (all extrinsic muscles) larynx (only 2 muscles) SUPRAHYOID: Elevate Hyoid Mandible 9 1 8 1 MYLOHYOID (CN V- Trigeminal) 2 7 DIGASTRIC Hyoid bone 3 9 ANTERIOR (CN V-Trigeminal) 7 POSTERIOR (CN VII- Facial) 6 8 STYLOHYOID (CN VII- Facial) 4 2 GENIOHYOID (CN XII- Hypoglossal + Cervical Spinal Nerves) 5 GENIOGLOSSUS (CN XII- Hypoglossal) Tongue muscles HYOGLOSSUS (CN XII- Hypoglossal) * In this diagram the mylohyoid has been flipped up (left side) and sternohyoid + omohyoid have been cut (right side) to depict the muscles that lie beneath INFRAHYOID “STRAP MUSCLES”: Depress Hyoid Depress Hyoid + Move Larynx “True Muscles” 4 STERNOHYOID (Cervical Spinal Nerves) 5 STERNOTHYROID (Cervical Spinal Nerves) 3 OMOHYOID (Cervical Spinal Nerves) *depress hyoid + larynx 6 THYROHYOID (Cervical Spinal Nerves) *depress hyoid + ELEVATE LARYNX INTRINSIC- connect within larynx Function: connect laryngeal cartilages connect muscles → change VF position + tension A ADDUCTORS G E LATERAL CRICOARYTENOIDS (2) F OBLIQUE ARYTENOIDS (2) F G TRANSVERSE ARYTENOID ABDUCTORS B A POSTERIOR CRICOARYTENOID C TENSORS E B CRICOTHYROID PARS RECTA + OBLIQUE D THYROVOCALIS D RELAXERS C THYROMUSCULARIS **CN X- Vagus: Superior branch → Cricothyroid **CN X- Vagus: Recurrent branch → ALL OTHERS AUXILIARY MUSCLES: SUPERIOR THYROARYTENOID- relaxes VF THYROEPIGLOTTIC- lubricates larynx ARYEPIGLOTTIC- protects airway c, 2022 Klaudia’s SLP Packets  ~VOCAL PARAMETERS~ FUNDAMENTAL FREQUENCY (FF)- number of VF vibrations per sec + controlled by intrinsic muscles Changes to Fundamental Frequency: Cricothyroid- INCREASES FF Thyrovocalis- INCREASES FF Thyromuscularis- DECREASES FF PITCH- direct relationship with frequency, measured in Hertz (Hz) *determined by age + gender *VOCAL JITTER (perturbation)- Optimal Pitch (Hz): cycle-by-cycle differences in vibration of the VF or the fundamental frequency MALE: 132 FEMALE: 212 CHILDREN: 300 (85-155 Hz) (165-255 Hz) (250- >300 Hz) INTENSITY- direct relationship with loudness (louder = longer ADDuction), measured in Decibels (dB) *controlled by INCREASES in: subglottal pressure lung alveolar pressure (8-12 dB) medial compression laryngeal tension *VOCAL SHIMMER- cycle-by-cycle differences in intensity VOCAL REGISTERS (3): Additional “Registers”: no VF vibration - WHISTLE- NOT “true” register (2500 Hz) MODAL or “modal phonation”- used in daily conversation - WHISPER- NOT “true” modal variation (variations: pressed + breathy) GLOTTAL FRY or pulse register- lowest register crackly sound caused by lowered subglottal pressure and tension of thyrovocalis + vibrating @ slower/aperiodic rate than normal FALSETTO- VF are tensed, thin, shortened + bowed only making brief contact VOICE DISORDER- when person’s voice QUALITY RESONANCE CLINICAL PARAMETERS (4): does not meet their daily needs with an abnormal production or absence of pitch, LOUDNESS/ vocal quality, loudness/intensity, or PITCH INTENSITY resonance VOICE MODIFICATION- when a person wants to change/alter their voice (NOT A VOICE DISORDER!) ex: social culture, professional use, gender identity, etc. c, 2022 Klaudia’s SLP Packets