Stimmlippbewegung

Stimmlippbewegung, also known as vocal fold vibration or glottal vibration, refers to the rapid opening and closing movements of the vocal folds (also called vocal cords) within the larynx during phonation. These movements are fundamental to voice production in humans and many animal species. When air from the lungs passes through the glottis—the space between the vocal folds—the pressure causes them to adduct (bring together). The Bernoulli principle and muscular tensions then facilitate their rapid oscillations.

The process begins with the adduction of the vocal folds, creating a closed glottal space. As air pressure increases beneath the folds, they are pushed apart, allowing air to escape. Once the airflow reduces the subglottic pressure, the vocal folds are drawn back together by elastic recoil and Bernoulli forces, resulting in a cyclical vibration. This oscillation modulates airflow into sound waves, producing voiced sounds such as vowels and voiced consonants.

Stimmlippbewegung is influenced by various factors, including muscle tension, subglottic pressure, and the length and mass of the vocal folds. The frequency of these vibrations determines pitch; faster vibrations yield higher pitches, while slower vibrations produce lower pitches. For instance, typical male speaking voices oscillate around 100 Hz, whereas female voices average around 200 Hz.

Understanding the biomechanics of stimmlippbewegung is essential in fields such as phonetics, speech therapy, and laryngology. Abnormalities in vocal fold vibration can lead to voice disorders like nodules, paralysis, or polyps, affecting voice quality and health. Research into vocal fold kinematics continues to improve diagnostic techniques and therapeutic interventions for such conditions.