The overall goal of this procedure is to visualize the tongue with ultrasound during speech, to use this information to evaluate speech errors and provide feedback to patients about their articulation. This method can help answer key questions in the field of speech language pathology. For example, what specifically is the client doing with the tongue while producing a distorted R sound?
The main advantage of this technique is that clinicians and researchers now have a way to visualize tongue movements during successful and unsuccessful attempts at a speech sound. The implications of this technique extend to better diagnosis and therapy for clients with speech sound disorders because we no longer have to guess about what's happening with the tongue during speech. Although this method can provide insight into the articulation of R, it's also a practical approach for learning about lingual articulations such as S, K, and L.Begin by positioning the participant comfortably in a chair, with his or her feet on the floor, back straight, and chin slightly forward.
Then, place a small amount of ultrasound gel on the ultrasound transducer. Next, position the transducer vertically, making tight contact with the skin underneath the chin, and applying a firm, but not an uncomfortable degree of pressure, to collect a sagittal image and visualize tongue from tip to root. Check the screen to verify that the transducer is properly oriented such that the front of the tongue is on the right of the screen, and the back of the tongue is on the left.
Angle the ultrasound transducer slightly forward or slightly back, depending on what part of the tongue is of interest. Instruct the participant to swallow to orient the user to the tongue position relative to the palate. Next, collect coronal images by rotating the ultrasound transducer 90 degrees to capture the tongue from the left to right side.
Instruct the participant to sustain sounds requiring midline grooving of the tongue. After imaging is complete, wipe off any excess gel and clean the transducer with the ultrasound-approved disinfecting wipe or spray. Begin by instructing the participant on the proper position of the ultrasound, and allow them to hold the ultrasound transducer.
In the sagittal view, observe the tongue between two major shadows created by bone, which is opaque to ultrasound. The shadow of the mandible, and the shadow of the hyoid. Instruct the participant to produce alveolar and velar sounds such as T, D, N, then K and G, to help orient both the participant and the clinician to which side of the image is the anterior tongue tip, and which side is posterior tongue dorsum.
In a sagittal view of a correct production of R, check to see that the anterior portion of the tongue elevates, while the back part of the tongue dorsum slopes backwards. To assess distorted R production, instruct the participant to imitate and sustain the R sound.Rrrr. Then, have the participant imitate the R sound in a number of syllables, such as:Ear.Ear.
Say rah.Rah. Say ree.Ree. Say roo.Roo.
Finally, rotate the probe 90 degrees to obtain a coronal view and observe the lateral margins of the tongue as the participant repeats the syllables er, ar, ear, rah, ree, and roo. Position the probe near the highest point of the tongue, about one-third of the distance between the chin and the throat in the sagittal plane. Orient the participant to ultrasound images in the sagittal section by asking the participant to point to the anterior and posterior regions of the tongue, or, front of the tongue and back of the tongue, respectively.
Teach the participant about the different parts of the tongue. Show the participant examples of good image quality and bad. Then, instruct the participant that R requires both an oral constriction in the front, and a pharyngeal constriction in the back.
Next, introduce the participant to different tongue shapes for the R sound using drawings, ultrasound images, or magnetic resonance images. Make it clear where the oral and pharyngeal constrictions are, but also acknowledge that every tongue shape is slightly different. Ask the participant to describe two major constrictions for R that are visible in a sagittal section.
If the participant cannot identify the oral and pharyngeal constrictions just described, continue to instruct. Then, orient the participant to ultrasound images in coronal section. Instruct the participant of the desired tongue shape from left to right.
Ask the participant to trace the tongue shape, identify the left and right edges, identify the center line groove, and explain the desired shape. Have the participant attempt to produce correct R in isolation, or in syllables by providing phonetic cues to copy different tongue shapes. Then, ask him or her to provide an explanation of what they did correctly or incorrectly after some of the attempts.
After the participant produces the correct sound, press the pause button to freeze the frame and discuss how this correct image looks different from previous incorrect productions. Finally, allow the participant to practice throughout the session without the ultrasound and offer the opportunity to successfully practice R without visual feedback. Here, a sagittal view of a magnetic resonance image during a correctly produced American English R with ultrasound image of the tongue is shown.
Notice the elevation of the anterior tongue and the lowering of the dorsum. On the other hand, in this incorrect or distorted production of the American English R, notice the low tongue tip and blade, and the raised tongue dorsum. This shows the mean accuracy on words containing R across 11 American English-speaking participants who were treated for R distortions.
After seven sessions of ultrasound biofeedback therapy, an upward trend in accuracy continues, suggesting that retention and generalization continued to occur. While attempting this procedure, it's important to remember to check the positioning of the probe. Don't let the probe rotate or slide, or the images will become distorted, and will be hard to interpret.
Following the use of ultrasound, traditional speech therapy should be included, to encourage successful attempts at speech sounds without visual feedback. Don't forget that ultrasound requires attention to safety, in particular, disinfecting the probe between uses, and also attempting to minimize exposure when possible. After watching this video, you should have a good understanding of how to collect ultrasound images of the tongue, and how to use this information to assess and provide feedback to patients about their tongue movements during speech.
