The Normal Swallow in Adults

In the following section, a basic overview of the stages of the normal swallow and the key events in each stage will be described. The procswallow.gifess of deglutition involves numerous anatomical structures and muscles which, as well as sensory and motor signals of cranial nerves V, VII, IX, X, XI and XII (Seikel, 2005). For more information on the cranial nerves involved in each stage of swallowing, please refer to the relevant references.
Normal swallowing depends on the rapid transferral of the bolus from the mouth to the stomach. Generally speaking, this process is accomplished by creating high pressure on the bolus, and low pressure below the level of the bolus. These changes in pressure are largely created by the control of various ‘valves’ along the process, which will be discussed in the following text (Croher & Crary, 2010).


According to Groher and Crary (2010 & 2003), swallowing can be divided in to four stages; oral preparation, oral stage, pharyngeal stage and oesophageal stage. While this distinction is helpful for understanding the swallowing process overall, it is important to remember that not all ‘normal’ swallows are exactly the same. Variability in swallowing can be seen between individual subjects, or may be due to the bolus type of the condition in which the swallowing occurs; such as the rate of eating, or conversing while eating (Groher & Crary, 2010).






References


Groher, M., & Crary, M. (2003). Introduction to adult swallowing disorders. Philadelphia, PA: Butterworth-Heinemann.

Groher, M., & Crary, M. (2010). Dysphagia: Clinical management in adults and children. Maryland Heights, MO: Mosby Elsevier.

Seikel, J., King, D., & Drumright, D. (2005). Anatomy & physiology for speech, language, and hearing (3rd ed.). Clifton Park, NY: Thomson Delmar Learning.