Physiological Flow of Liquids Used in Dysphagia Management (Neuro)

This observational research study will measure swallowing function in individuals with Amyotrophic Lateral Sclerosis or Parkinson's disease. The aims of this study are to (1) identify parameters of swallowing physiology that are associated with impaired swallowing safety and efficiency, and (2) explore how liquid thickness influences swallowing function. Participation in this research study involves a single appointment at the University of Florida Swallowing Systems Core laboratory located at Shands Hospital, Gainesville. The appointment will last approximately 1 hour, and will involve tasks to measure tongue-strength, and a dynamic swallowing x-ray (known as videofluoroscopy) to evaluate swallowing function. A selection of demographic information (e.g., age, onset of symptoms) will also be recorded. To measure tongue strength, participants will be given a disposable air-filled bulb and asked to perform a series of tongue presses, and swallow their saliva. Next, during the videofluoroscopy, participants will take sips of various liquids ranging in thickness from thin (like water), to extremely-thick (similar to the consistency of pudding or yogurt). The liquids will be mixed with a safe substance called barium, to make them visible on x-ray images. After the videofluoroscopy has been completed, each participant will have their tongue strength measured again, which will conclude their participation in the study. Swallowing physiology will be measured from the videofluoroscopy images, post-hoc, by an experienced team of blinded raters.