What do normal swallowing physiology phases include?

The normal swallowing physiology phases consist of distinct stages that accurately describe the complex process of swallowing. The correct answer highlights these well-defined phases: oral preparatory, oral transit, pharyngeal, and esophageal.

In the oral preparatory phase, food is manipulated in the mouth and mixed with saliva to form a cohesive bolus, which is essential for effective swallowing. This phase involves several movements, including chewing and positioning the food for swallowing.

Following this, the oral transit phase occurs when the bolus is moved from the front of the mouth to the back, triggering the swallowing reflex. This motion is critical as it sets off the next phase of swallowing.

The pharyngeal phase begins as the bolus reaches the oropharynx, where several reflexive actions occur to ensure the airway is protected, and the bolus is directed into the esophagus.

Finally, the esophageal phase involves the movement of the bolus down the esophagus, which is facilitated by peristaltic contractions and the coordination of the upper and lower esophageal sphincters.

These specific phases together ensure the effective and safe passage of food from the mouth to the stomach, making option B the accurate reflection of normal swallowing physiology.