Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Graduation

Fall 12-17-2011

Document Type


Degree Name

Doctor of Philosophy (PhD)


Department of Communication Sciences and Disorders


Christy Ludlow

Cynthia O'Donoghue

Charles Runyan


The purpose of this study was twofold: to determine the effects of two types of non-invasive, peripheral sensory stimulation on the frequency of infant swallowing and to explore the cortical activation patterns in response to stimulation in the somatosensory and motor regions of the brain during infancy, between 2-4 months and 7-9 months of age. The two different forms of mechanical stimulation investigated include pacifier stimulation to the lips and oral cavity and vibrotactile stimulation via the external throat area to the laryngeal tissues. The study represents a prospective, repeated experimental research design. Investigators utilized an accelerometer and an inductive plethysmography system to identify swallowing events and functional near-infrared spectroscopy (NIRS), a non-invasive cortical optical-imaging technique, to cortical responses to the peripheral stimulation conditions by measuring the hemodynamic responses in cortical oral-motor and sensorimotor regions. A repeated-measures ANOVA was performed on the participants’ swallowing frequency data with and without the stimulation conditions. The results indicated a significant difference (p < .001) among the three conditions (no stimulation, pacifier stimulation, and vibrotactile stimulation), with pairwise comparisons indicating that the pacifier and vibrotactile conditions significantly (p < .001) increased the infants’ swallowing frequency compared to swallowing frequency without stimulation. Swallowing frequency did not differ between the pacifier and vibrotactile conditions (p > .05). NIRS recordings were obtained on only a few subjects for technical reasons. NIRS pilot data changes in blood flow occurred during the pacifier and vibrotactile stimulation conditions in a few infants. Overall findings suggest that both pacifier and vibrotactile stimulation can serve to up-regulate the frequency of swallowing in normal infants. Non-nutritive pacifier stimulation may be beneficial for increasing the frequency of swallowing in infants in addition to the known benefits of aiding in sucking skills development. Vibrotactile stimulation represents an alternative or complementary intervention for increasing the frequency of swallowing in infants that may not interfere with the process of oral intake. The current study continues to collect data for normal infants and should be explored in infants with disordered swallowing, particularly in the neonatal intensive care unit.



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