Within the United States alone, over a half-million infants are born premature each year. While medical advances have dramatically improved survival rates, long-term morbidities related to auditory function are common. The preterm population suffers from a relatively high prevalence of sensorineural hearing loss, auditory neuropathy/dys-synchrony, and central auditory processing disorder. Even preterm infants in whom no specific auditory pathology has been diagnosed exhibit cognitive impairments related to auditory processing, including auditory attention deficits, language processing deficits, and other speech/language communication deficits. Despite these facts, a solid understanding of the impact of premature birth on auditory neurodevelopment is lacking. Possible effects of the acoustic environment are unknown. The long-term objective of this research is to characterize the effect of premature birth on auditory neurodevelopment and communication behavior to aid in improving best medical practices and therapeutic interventions for preterm infants. In this study, we propose to measure the effects of auditory input during the preterm period on neurodevelopmental outcomes. There are three specific aims. In Aim 1 we will recruit a cohort of preterm infants in the neonatal intensive care unit (NICU) to prospectively measure their auditory input during hospital stay. We will quantify detailed auditory experience in the NICU and determine how this differs from intrauterine auditory experience. In Aim 2 we will determine the effect of premature birth on auditory function at 3 months of age. In Aim 3 we will determine the relationship between our measured parameters of perinatal auditory experience and auditory function in infancy. The proposed study will lay the foundation for a longitudinal study aimed to determine the effect of auditory experience in the NICU on long-term auditory and language development. Valuable insight will be gained as to how premature birth and NICU environment might affect auditory neurodevelopment. Results of these studies will ultimately aid in identifying (1) effective interventions to optimize NICU auditory experience and (2) potential early-intervention therapies for NICU infants at greatest risk for auditory and language deficits later in childhood.