Department of Pediatrics, Keio University School of Medicine, Shinjuku, Tokyo 160-8582, Japan.
Department of Psychology, Faculty of Letters, Keio University, Kohoku-ku, Yokohama 223-8521, Japan.
Neuroimage Clin. 2018 May 15;19:599-606. doi: 10.1016/j.nicl.2018.05.005. eCollection 2018.
Higher brain dysfunction, such as language delay, is a major concern among preterm infants. Cerebral substrates of cognitive development in preterm infants remain elusive, partly because of limited methods. The present study focuses on hemodynamic response patterns for brain function by using near-infrared spectroscopy. Specifically, the study investigates gestational differences in the hemodynamic response pattern evoked in response to phonetic changes of speech and cerebral hemispheric specialization of the auditory area in preterm infants ( = 60) and term infants ( = 20). Eighty neonates born between 26 and 41 weeks of gestational age (GA) were tested from 33 to 41 weeks of postmenstrual age (PMA). We analyzed the hemodynamic response pattern to phonemic and prosodic contrasts for multiple channels on temporal regions and the laterality index of the auditory area. Preterm infants younger than 39 weeks of PMA showed significantly atypical hemodynamic patterns, with an inverted response shape. Partial correlation analysis of the typicality score of hemodynamic response revealed a significant positive correlation with PMA. The laterality index of preterm infants from 39 weeks of PMA demonstrated a tendency rightward dominance for prosodic changes similar to term infants. We provide new evidence that alterations in hemodynamic regulation and the functional system for phonemic and prosodic processing in preterm infants catch up by their projected due dates.
早产儿的大脑功能障碍，如语言发育迟缓，是一个主要关注点。早产儿认知发育的大脑基础仍然难以捉摸，部分原因是方法有限。本研究通过近红外光谱技术关注大脑功能的血液动力学反应模式。具体来说，该研究调查了早产儿（n=60）和足月产儿（n=20）在言语语音变化诱发的血液动力学反应模式和听觉区大脑半球专门化方面的胎龄差异。80 名胎龄在 26 至 41 周（GA）之间的新生儿在出生后 33 至 41 周的胎龄（PMA）时进行了测试。我们分析了对时间区域多个通道的语音和韵律对比的血液动力学反应模式以及听觉区的侧化指数。胎龄小于 39 周的早产儿表现出明显的非典型血液动力学模式，呈倒置反应形状。血液动力学反应典型性得分的偏相关分析显示与 PMA 呈显著正相关。39 周 PMA 的早产儿的侧化指数对韵律变化表现出右偏优势，类似于足月产儿。我们提供了新的证据，表明早产儿的血液动力学调节和语音韵律处理功能系统的改变可以通过预期的预产期赶上。
