Phonation and Laryngeal Mechanics - Study Notes (copy)

Phonation

The production of voiced sound using air under pressure to generate the acoustic sound source for speech.

Larynx functions

Voice production (phonation), pitch control, loudness, voice quality, as well as roles in biological functions like breathing, swallowing, and coughing.

Location of larynx

Sits on top of the trachea, controls passage between upper and lower respiratory tracts, and protects the airway.

Hyoid bone

The only bone in the body not attached to another bone, allowing for movement that assists in phonation.

True vocal folds

The sound source in phonation, consisting of vocal ligaments and thyroarytenoid muscle.

Glottis

The variable space between the vocal folds.

False vocal folds

Also known as ventricular folds, located above true vocal folds, lubricate true folds but do not produce phonation.

Cuneiform cartilages

Small cartilages embedded within the aryepiglottic folds.

Quadrangular membrane

Spans from the lateral border of the epiglottis to the arytenoids; forms part of the aryepiglottic folds.

Supraglottal cavity

The space above the true vocal folds, also known as the vestibule.

Laryngeal ventricle

Small cavity between the false and true vocal folds, lined with mucous membranes.

Subglottal cavity

The space below the true vocal folds, just above the trachea.

Piriform sinus

A space on the outer side of the quadrangular membrane.

Cricoarytenoid joint

Allows complex rocking and sliding movements of the arytenoids to control vocal fold position.

Adduction

The movement of vocal folds toward the midline to produce voiced sounds.

Abduction

The movement of vocal folds away from the midline to permit inhalation and voiceless sounds.

Cricothyroid joint

Joint between cricoid and thyroid that enables complex rotation and sliding, responsible for high pitch when contracted.

Glottal cycle

The repeated adduction and abduction of vocal folds that generates sound through phonation.

Phonation Threshold Pressure (PTP)

The minimal alveolar pressure needed to initiate a glottal cycle.

Fundamental frequency (Fo)

The number of glottal cycles per second, determining vocal pitch.

Loudness

The perceptual correlate of vocal intensity, linked to alveolar pressure and glottal closure.

Voice Quality

Describes the perceptual attributes of the voice beyond pitch and loudness, such as breathiness and strain.

Vocal nodules

Callous-like growths from constant voice use that affect voice quality.

Laryngitis

Inflammation of laryngeal tissues affecting voice quality.

Aeromechanical measures

Techniques used to assess laryngeal air flow and resistance.

Velopharyngeal mechanism

Regulates the opening between oral and nasal cavities, essential for shaping sounds.

Velum (soft palate)

Attached to the palatine bone, it acts with the pharyngeal walls to regulate airflow during speech.

Nasal resonance

The effect of the velopharyngeal mechanism on sound quality and intelligibility.

Subglottal pressure

The pressure below the vocal folds that influences loudness and phonation dynamics.

Vocal fold tension

The degree of tightness of the vocal folds affects pitch and voice quality.

Medial compression

The muscular force that brings vocal folds toward the midline, affecting glottal pressure.

Phonatory health

Considerations regarding proper voice use to avoid injuries such as nodules or laryngeal inflammation.

Clinical voice evaluation

Assessments using endoscopes and aeromechanical measures to diagnose voice disorders.

Respiratory dynamics

The interplay of respiration, muscle control, and acoustics in phonation.

Endoscopy

A procedure to visually assess the larynx for voice quality and pathology.

Vital capacity

The maximum amount of air that can be expelled from the lungs after maximum inhalation.

Breath holding

An activity where the glottis is adducted to trap inhaled air.

Whisper

Phonation technique with no vocal fold vibration, using a turbulent airstream for sound.

High-speed imaging

Technique to record laryngeal activity at high frame rates for analysis.

Aryepiglottic folds

Folds located at the lateral border of the epiglottis, contributing to airway protection.

Voice pathologies

Conditions affecting voice quality such as nodules and laryngitis.

Pharyngeal cavity

The space within the throat involved in sound production and resonance.

Acoustic filtering

The process by which certain frequencies are amplified or attenuated as sound passes through spaces.

Sound radiation

The process of sound emanating from the vocal tract during speech.

Intelligibility

The clarity with which speech can be understood, influenced by phonation and resonance.