Two innovative approaches, pulsatile orocutaneous entrainment of non-nutritive suck via orosensory entrainment (NTrainer) device technology and serial salivary gene expression analyses, will be merged to examine the relation between gene expression, oral somatosensory stimulation, feeding behavior, and neurodevelopmental outcomes at 18 months corrected age (CA) on 180 extremely preterm infants [EPIs] (24 0/7-26 6/7 GA and 27 0/7 - 28 6/7 GA) enrolled at three neonatal intensive care units: Catholic Health Initiative (CHI) Health St. Elizabeth (Lincoln, NE), Tufts Medical Center (Boston, MA), and Santa Clara Valley Medical Center (San Jose, CA). EPIs will be randomized to a blind pacifier (SHAM) or PULSED NTrainer treatment groups, and stratified by GA, sex, and bronchopulmonary dysplasia status (BPD vs non-BPD). We hypothesize that the combination of the NTrainer® intervention for improved oral feeding skills, along with objective salivary gene expression data to monitor response to treatment and feeding development, will result in a novel, objective, and personalized approach to neonatal oral feeding and reduce the duration of time to attain oral feeds while improving feeding, growth and neurodevelopmental outcomes at 18 months' CA.