The Normal Swallow
Swallowing is a complex process
that results from a carefully orchestrated sequence
of events involving the brain, nerves, and muscles
of the mouth, throat, and esophagus.
When drinking or eating, the swallowing process
begins as the first bite or sip is placed in the
mouth. The lips maintain adequate closure
to prevent liquids and solids from escaping. Jaw
and tongue muscles must be strong and coordinated
to allow the successful chewing of solids. Sensory
receptors in the mouth allow us to taste the food
and perceive where the food or liquid is. The
tongue moves efficiently to control what has been
put within the mouth, and when ready to swallow,
the tongue cradles and transfers what is being
eaten from the mouth into the throat (pharynx).
As this occurs, the brain receives sensory information
that instructs the muscles of the neck and throat
to be in motion.
This is the beginning of the pharyngeal
aspect of the swallow During the "pharyngeal
swallow," several critical things occur.
As the food or liquid reaches the throat (pharynx)
from the mouth, the muscular bulk of the tongue
swiftly pushes what is being swallowed to
propel it through the throat toward the esophagus.
The soft palate closes the mouth from the nose
to prevent food or liquid from entering the nasal
cavity. Simultaneously, the voicebox (larynx),
which is actually part of the breathing system,
closes tightly. This prevents what is being
swallowed from passing into the air passage by
mistake. Along with airway closure, the
entrance to the esophagus opens to receive what
is being swallowed. It is during the pharyngeal
swallow that movement of the larynx can be felt
within the throat.
Once the food or liquid is within the esophagus,
it rhythmically passes downward through the body
and ultimately into the stomach. Dysphagia,
or swallowing impairment, can result when there
is disruption in any aspect of this complicated
process.
What
is a Swallowing Disorder?
Signs
and Symptoms of a swallowing disorder
Types of
Swallowing Disorders
Evaluation
and Treatment
Living with
Dysphagia
