Essay On Deglutition
The three phases of deglutition in order are the voluntary phase, pharyngeal phase, and the esophageal phase. Each phase has various neural involvement. During the voluntary phase, the temporal lobes and motor cortex of the cerebral cortex are involved (McKinley 1031). The voluntary phase is characterized by forming the chewed food into a ball (now called a “bolus”) and moving it towards the rear of the mouth. Now begins the pharyngeal phase.
This phase is characterized by movement of the bolus through the pharynx to the superior esophageal sphincter. There are several mechanisms to achieve this movement, which can be summarized as the swallowing reflex. The swallowing reflex is …show more content…
The cardiac sphincter itself is not strong enough to keep stomach contents inside alone, rather it is aided by the diaphragm. If it “loosens” too much, stomach contents containing stomach acid can erupt into the esophagus causing severe pain. A hiatal hernia is when the stomach moves superiorly through the esophageal hiatus, thus removing the diaphragm’s assistance to the cardiac sphincter. Stomach contents then erupt even more easily into the esophagus! The cardiac sphincter is kept relatively relaxed while eating (Goyal), which can exacerbate GERD even more in the event of a hiatal