Bolus position at swallow onset in normal adults: preliminary observations.

A "delayed swallowing reflex/response" (i.e., when the swallow reflex is not triggered when the bolus passes the back of the tongue at the anterior facial arch) Logemann has been widely accepted as an abnormality. Careful review of the literature supports the premise that a "delayed swallowing reflex/response" may in fact be a variation of normal. This paper describes swallowing in normal adults. We report the videofluoroscopic measurements of bolus position at the onset of swallow. A radiopaque marker was affixed to the anterior facial arch and the distance between the head of the bolus and the anterior facial arch was measured at the onset of swallow. A statistically significant proportion of swallows (22 of 30) occurred after the head of the bolus passed the anterior facial arch. This finding suggests that there may be diverse sites for elicitation of the swallowing response/reflex rather than a single site (i.e., the anterior facial arch). The relevance of this finding to treatment using thermal stimulation is discussed, as is the versatility of the normal pharynx.