What is the function of a pneumotachograph in speech measurement?

The function of a pneumotachograph in speech measurement is to measure air flow during speech. This device is essential for studying respiratory aspects of speech production, as it provides quantitative data on the airflow that occurs when a person speaks. By evaluating this airflow, researchers and clinicians can gain insights into various speech characteristics, including the efficiency of speech production and the dynamics of respiratory patterns.

The pneumotachograph typically works by detecting changes in pressure as air passes through it, allowing for precise measurements of how much air is inhaled and exhaled during speech. This information is crucial for understanding voice quality, speech disorders, and the mechanics of respiration related to phonation.

In contrast, options related to measuring chest wall displacement, tongue movement, and vocal fold vibration focus on different aspects of speech and do not utilize the pneumotachograph's capabilities. While those factors are also important in speech science, they require different measurement techniques and tools.