We also plan to compare discrete and continuous swallowing in these populations. While the motor physiology for discrete swallowing (i.e., single swallow) has been well studied, little is known about the details of oral, laryngeal, and pharyngeal coordination during sequential swallowing as a part of continuous drinking--a common event in everyday eating. A portion of the protocol will study the effects of fast-paced movement sequencing on the coordination of the tongue, velum, larynx, and pharynx during continuous drinking. Videofluoroscopy and ultrasound may be paired or used individually to collect data from normal subjects and patients with known dysphagia while they perform sequential and discrete swallowing tasks. A number of timing and displacement measurements of the structures activated during these tasks will be made from the digitized video images of each swallow, and analyses will be carried out subsequently across tasks and subjects.