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The interaction between breast and infant's mouth, during breastfeeding, is a complex dynamic mechanism. It remains unclear which factor plays the key role in removing milk from the breast: the intra-cavity vacuum pressure or the compressive pressure of the tongue. While there are extensive clinical data on collection of vacuum pressure, limited data exist for the positive pressure values on the breast areola exerted by infant's mouth. The goal of this study is to use a methodology to capture these positive pressure values exerted by maxilla and mandible on the breast areola during breastfeeding. In this study, the positive and negative (vacuum) pressure values are obtained simultaneously on seven lactating mothers successfully. Parallel to the pressure data measurements, ultrasound images are captured and processed to reveal the nipple deformations and the displacements of infants' tongues and jaw movements during breastfeeding. At the end, motivated by the significant differences in composition between the tissue of the breast and the nipple-areola complex, the Poisson's ratio values of the lactating nipples are obtained using these deformation measurements.
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Regional tongue deformations during chewing and drinking in the pig
Abstract As a muscular hydrostat, the tongue undergoes complex deformations during most oral behaviors, including chewing and drinking. During these behaviors, deformations occur in concert with tongue and jaw movements to position and transport the bolus. Moreover, the various parts of the tongue may move and deform at similar timepoints relative to the gape cycle or they may occur at different timepoints, indicating regional biomechanical and functional variation. The goal of this study is to quantify tongue biomechanics during chewing and drinking in pigs by characterizing intrinsic deformations of the tongue across multiple regions simultaneously. Tongue deformations are generally larger during chewing cycles compared to drinking cycles. Chewing and drinking also differ in the timing of regional length and width, but not total length, deformations. This demonstrates functional differences in the temporal dynamics of localized shape changes whereas the global properties of jaw-tongue coordination are maintained. Finally, differences in the trade-off between length and width deformations demonstrate that the properties of a muscular hydrostat are observed at the whole tongue level, but biomechanical variation (e.g., changes in movements and deformations) at the regional level exists. This study provides new critical insights into the regional contributions to tongue deformations as a basis for future work on multidimensional shape changes in soft tissues.
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- Award ID(s):
- 1725925
- PAR ID:
- 10310039
- Date Published:
- Journal Name:
- Integrative Organismal Biology
- Volume:
- 3
- Issue:
- 1
- ISSN:
- 2517-4843
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/iob/obab012
