There are 50 different muscle pairs and countless nerves responsible for receiving food into the mouth, preparing it for digestion, and transporting it from the mouth to the stomach. This process of swallowing occurs in three stages: 1.) the oral stage, 2.) the pharyngeal phase, and 3.) the esophageal phase. Dysphagia can occur in any stage. For example, weak tongue muscles may make it challenging to move food around the mouth for proper chewing. Or, a stroke or other neurological condition can disrupt the swallowing response. There are many possible causes for dysphagia, including cancer, birth defects (e.g., cleft lip or cleft palate), nervous system disorders, injury, and infection. To properly diagnose dysphagia, a speech language pathologist or physician may use a battery of tests, including a barium swallow or a Flexible Endoscopic Evaluation of Swallowing with Sensory Testing (FEESST), which uses a lighted tube to evaluate the swallowing mechanism. Treatment may involve changing food size or texture and head and neck posture as well as performing exercises to strengthen facial muscles and improve coordination. If the dysphagia is so severe that an individual is unable to get the necessary nutrients, surgery or use of a feeding tube may be necessary.