The premature infant, deprived of normal developmental benefits of the uterus, is at risk for later learning disabilities, delays in speech and language development, and neurological disorders, such as cerebral palsy. At present, it is estimated that approximately 11-12% of all births will occur prior to completion of the 37th gestational week and that more infants are surviving at a younger age, thereby experiencing earlier exposure to the unfiltered stimuli of the neonatal intensive care unit. The costs are very high in both risks and dollars, with hospital charges for infants diagnosed with prematurity/low birth weight exceeding $18 billion a year.
The mother's voice, hypothesized to stimulate maturation of sensory systems and help shape normal development, is this applicant's focus because it is a predominant source of multimodal stimulation for the developing fetus and is abruptly lost at birth by preterm infants. When the fetus's mother speaks, not only does her baby hear her voice?her baby feels her vertebral column and diaphragm gently vibrate and move in sync with her voice?so the fetus receives multiple forms of sensory stimulation. The neonatal intensive care unit environment, with its unfiltered noise levels and diminished exposure to maternal voice, stands in sharp contrast to the ideal fetal environment of the mother's womb.
Using differing yet overlapping psychological perspectives the proposed study seeks to extend fetal pilot findings for the purpose of adding to our basic knowledge of not only when, but ultimately how, humans learn and remember. A longitudinal design will be used to provide six weeks of daily auditory experience (mother reciting a rhyme) in conjunction with weekly testing (stranger reciting the same rhyme) to describe and interpret how the fetus responds to the familiar passage. This new information will assist in unraveling important aspects of this complex developmental time period, and findings will provide a foundation for making future comparisons between normal fetal and preterm cognitive development. This will, in turn, generate the kind of data needed to address broader societal priorities: 1) designing interventions that incorporate exposure to maternal voice to decrease risk of cognitive disabilities in preterm infants, and 2) attracting undergraduate and graduate nursing students to this research area. If exposing preterm infants to maternal voice via simple recordings (since real voice contact has been greatly diminished due to care provided within the neonatal intensive care unit) is a critical factor in preterm cognitive development, then it is long overdue for more intensive study.
