What does electropalatography (EPG) primarily record?

Electropalatography (EPG) primarily records tongue movement by using a system of electrodes embedded in a plate placed on the hard palate. As the tongue comes into contact with these electrodes during speech, the pattern of contact is recorded, providing valuable data on tongue position and movement. This is particularly useful in studying speech production and articulation, as it allows clinicians and researchers to visualize and analyze the dynamics of tongue movement in real time.

The other options, while related to speech sciences, do not accurately describe the main function of EPG. Laryngeal vibration pertains to phonation and is typically measured through other methods, such as electroglottography or laryngoscopy. Airflow would be studied using different instruments designed to measure respiratory function or airflow rates, rather than the tongue's articulation. Similarly, chest wall displacement correlates with respiratory mechanics, which are recorded through different techniques like respiratory inductance plethysmography but not EPG. Therefore, the focus of EPG on tongue movement is what differentiates it from these other measures in speech science.