Pacifier stiffness alters the dynamics of the suck central pattern generator

Abstract

Variation in pacifier stiffness on non-nutritive suck (NNS) dynamics was examined among infants born prematurely with a history of respiratory distress syndrome. Three types of silicone pacifiers used in the NICU were tested for stiffness, revealing the Super Soothie â nipple is 7 times stiffer than the Wee Soothie â or Soothie â pacifiers. Suck dynamics among 20 preterm infants were subsequently sampled using the Soothie â and Super Soothie â pacifiers during follow-up at approximately 3-months of age. ANOVA revealed significant differences in NNS cycles/min, NNS amplitude, NNS cycles/burst, and NNS cycle periods as a function of pacifier stiffness. Infants modify the spatiotemporal output of their suck central pattern generator when presented with pacifiers with significantly different mechanical properties. Infants show a non-preference to suck due to high stiffness in the selected pacifier. Therefore, excessive pacifier stiffness may decrease ororhythmic patterning and impact feeding outcomes.

Synthetic orocutaneous stimulation entrains preterm infants with feeding difficulties to suck

“…30 The results from the present study demonstrate the potent effects of a motorized pacifier nipple on the development of NNS in preterm infants. The patterned orocutaneous experience is physiologically salient and spectrally patterned to resemble the 'burst-pause' structure of the NNS.…”

Short-Term Effects of Pacifier Texture on NNS in Neurotypical Infants

“…A Nellcor OxiMAX N-600X pulse oximeter sensor was placed around each infant's wrist to monitor pulse rate and oxygen saturation (SpO 2 ) throughout the study. Similar to the pacifier preference design described in the work by Zimmerman and Barlow [25], the present protocol consisted of 2-minute suck samples to assess the short-term effects of texture arrays on ororhythmic output. Four suck samples were obtained, including 3 samples with textured silicone pacifiers and 1 sample with a regular Soothie pacifier.…”

“…Thus, afferent sensory information is important for error correction in movement or rhythmicity, as well as counteracting any unexpected perturbations in the environment [18, 19]. It has been shown that the sCPG is highly responsive to peripheral input and adapts to changes in task dynamics and local environment, such as volume and consistency of a liquid bolus or mechanical properties of a nipple [21–25]. Sensory flow from the trigeminofacial pathway also modulates the sCPG by tuning the sensitivity of orofacial reflexes [18, 26, 27], with young term infants demonstrating perioral reflex sensitivity to punctate mechanical inputs at a latency of approximately 18–21 milliseconds [28].…”

“…Early studies found that certain characteristics of a nipple or pacifier (e.g., size and shape) can influence NNS frequency [48, 49]. Recently, Zimmerman and Barlow [25] discovered that pacifier stiffness can alter the fine structure of the NNS. The present study extends these observations to consider the short-term effects of pacifier texture on ororhythmic patterning in term infants.…”

Perioral movements and sucking pattern during bottle feeding with a novel, experimental teat are similar to breastfeeding

“…Zimmerman and Barlow 4 reported that excessive stiffness may decrease ororhythmic patterning and impact feeding outcome. In addition, previous studies have revealed that there are many differences in variables with regard to feeding or sucking behavior such as perioral movements, 5,6 intraoral (tongue) movements, [7][8][9] intraoral pressure changes, 10-12 the angle of mouth opening 6 and flow rates.…”