tongultrasound

Tongultrasound is the use of ultrasonography to visualize the tongue's shape and movement in real time. In research and clinical practice, it is employed to study articulation, swallowing, and tongue control. The technique provides a noninvasive view of the tongue surface and dorsum, complementing other imaging methods such as MRI and videofluoroscopy.

Technique and data: A high-frequency ultrasound transducer is typically placed under the chin (submental) with a water-based coupling medium. The patient or participant produces speech while the device records sagittal-plane images of the tongue. Images are usually shown as two-dimensional B-mode, with some systems offering M-mode to track motion over time or 3D reconstructions.

Applications: In phonetics, tongultrasound reveals tongue position for vowels and many consonants, aiding experiments on articulation. Clinically, it supports assessment of dysarthria and dysphagia and provides real-time feedback in speech therapy.

Advantages and limitations: It is noninvasive, safe, and relatively portable compared with MRI. It provides dynamic information about movement. Limitations include a focus on the tongue surface and dorsum, variable image quality, interference from teeth and saliva, and the need for specialized training to interpret the images.

History: Tongultrasound emerged as a practical tool in the late 20th century alongside advances in medical ultrasonography. Its use in speech science has grown with improvements in transducer design and image processing.

See also: Ultrasound imaging, Tongue, Articulatory phonetics, Dysphagia.