Objectives: By measuring event-related brain potentials (ERP) we tested the sensitivity of the newborn auditory cortex to sound lateralization and to the most common cues of horizontal sound localization. Design: Sixty-eight healthy full-term newborn infants were presented with auditory oddball sequences composed of frequent and rare noise segments in four experimental conditions. We tested in them the detection of deviations in the primary cues of sound lateralization (interaural time and

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... difference) and in actual sound source location (free-field and monaural sound presentation). ERP correlates of deviance detection were measured in two time windows. Results : Deviations in both primary sound localization cues as well as in the ear of stimulation elicited a significant ERP difference in the early (90-140 ms) time window. Deviance in actual sound source location (the free-field condition) elicited a significant response in the late (290-340 ms) time window. Conclusions: The early differential response may indicate the detection of a change in the respective auditory features. We suggest that the late differential response, which was only elicited by actual sound source location deviation, reflects the detection of location deviance integrating the various cues of sound source location. Although the results suggest that all of the tested binaural cues are processed by the neonatal auditory cortex, utilizing the cues for locating sound sources of these cues may require maturation and learning.