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Coordinate Mapping of Hyolaryngeal Mechanics in Swallowing
Published on: May 6, 2014
Pressure and Timing Differences Between Volitional and Non-Cued Saliva Swallows Measured with Pharyngeal
Maryann N Krasko1,2, Corinne A Jones3,4, Michelle R Ciucci5,6,7
1Department of Otolaryngology-Head & Neck Surgery, University of Wisconsin-Madison, 1300 University Ave, Madison, WI, 53706, USA. mkrasko@uiowa.edu.
Dysphagia
|July 28, 2026
Summary
Healthy adults generate higher pharyngeal pressures during volitional swallows compared to spontaneous saliva swallows. These findings suggest volitional swallowing assessments can effectively represent spontaneous function in clinical evaluations.
Area of Science:
- Physiology
- Swallowing Mechanics
- Neuroscience
Background:
- Swallowing research often overlooks spontaneous saliva swallows, focusing instead on cued volitional swallows.
- Differences in sensory input and neural activation may lead to distinct physiological patterns between swallow types.
- Pharyngeal high-resolution manometry (Hrm) is a valuable tool for analyzing the nuances of both volitional and spontaneous swallowing.
Purpose of the Study:
- To compare pressure generation and timing during cued volitional and non-cued saliva swallows in healthy adults.
- To investigate potential differences in swallowing physiology based on swallow type.
- To determine if volitional swallowing assessments can serve as reliable indicators of spontaneous swallowing function.
Main Methods:
- Fifty healthy adults (25 males, 25 females) participated in the study.
- Pharyngeal high-resolution manometry (Hrm) was used to measure pressures during swallowing.
- Data were analyzed using paired t-tests to compare pressure generation and timing events between cued volitional (2 cc thin liquid) and non-cued saliva swallows.
Main Results:
- Significantly greater pressures were generated during volitional swallows in the velopharynx, tongue base, and UES (post-closure) regions compared to saliva swallows.
- No significant pressure differences were observed in the hypopharynx between the two swallow types.
- Volitional swallows exhibited longer UES relaxation durations than saliva swallows, and positive linear relationships were found between swallow types for velopharyngeal and tongue base pressures.
- No significant sex-based differences were found in swallowing outcome measures, despite differences in C2-C4 size.
Conclusions:
- Healthy adults produce higher pressures during volitional swallows than spontaneous saliva swallows in most pharyngeal areas, with the hypopharynx being an exception.
- The strong correlation between swallow types suggests that volitional swallowing assessments can be clinically relevant proxies for spontaneous function.
- The absence of sex-based differences supports the uniform interpretation of manometric results across adult populations, highlighting the importance of considering swallow type in clinical practice.
