Stephen Julia M, Hill Dina E, Peters Amanda, Flynn Lucinda, Zhang Tongsheng, Okada Yoshio
The Mind Research Network, University of New Mexico Health Sciences Center, Albuquerque, NM, USA.
Dev Neurosci. 2017;39(5):430-441. doi: 10.1159/000477614. Epub 2017 Aug 4.
The cortical responses to auditory stimuli undergo rapid and dramatic changes during the first 3 years of life in normally developing (ND) children, with decreases in latency and changes in amplitude in the primary peaks. However, most previous studies have focused on children >3 years of age. The analysis of data from the early stages of development is challenging because the temporal pattern of the evoked responses changes with age (e.g., additional peaks emerge with increasing age) and peak latency decreases with age. This study used the topography of the auditory evoked magnetic field (AEF) to identify the auditory components in ND children between 6 and 68 months (n = 48). The latencies of the peaks in the AEF produced by a tone burst (ISI 2 ± 0.2 s) during sleep decreased with age, consistent with previous reports in awake children. The peak latencies of the AEFs in ND children and children with autism spectrum disorder (ASD) were compared. Previous studies indicate that the latencies of the initial components of the auditory evoked potential (AEP) and the AEF are delayed in children with ASD when compared to age-matched ND children >4 years of age. We speculated whether the AEF latencies decrease with age in children diagnosed with ASD as in ND children, but with uniformly longer latencies before the age of about 4 years. Contrary to this hypothesis, the peak latencies did not decrease with age in the ASD group (24-62 months, n = 16) during sleep (unlike in the age-matched controls), although the mean latencies were longer in the ASD group as in previous studies. These results are consistent with previous studies indicating delays in auditory latencies, and they indicate a different maturational pattern in ASD children and ND children. Longitudinal studies are needed to confirm whether the AEF latencies diverge with age, starting at around 3 years, in these 2 groups of children.
在正常发育（ND）儿童生命的头3年中，皮层对听觉刺激的反应会经历快速而显著的变化，主要峰值的潜伏期缩短，幅度也发生改变。然而，以往大多数研究都集中在3岁以上的儿童。对发育早期阶段的数据进行分析具有挑战性，因为诱发反应的时间模式会随年龄变化（例如，随着年龄增长会出现额外的峰值），且峰值潜伏期会随年龄缩短。本研究利用听觉诱发磁场（AEF）地形图来识别6至68个月的ND儿童（n = 48）中的听觉成分。睡眠期间由短纯音（刺激间隔2 ± 0.2秒）产生的AEF峰值潜伏期随年龄缩短，这与之前对清醒儿童的报道一致。比较了ND儿童和自闭症谱系障碍（ASD）儿童的AEF峰值潜伏期。以往研究表明，与年龄匹配的4岁以上ND儿童相比，ASD儿童的听觉诱发电位（AEP）和AEF初始成分的潜伏期延迟。我们推测，被诊断为ASD的儿童的AEF潜伏期是否会像ND儿童一样随年龄缩短，但在大约4岁之前潜伏期普遍更长。与该假设相反，ASD组（24至62个月，n = 16）在睡眠期间（与年龄匹配的对照组不同）峰值潜伏期并未随年龄缩短，尽管ASD组的平均潜伏期如以往研究一样更长。这些结果与之前表明听觉潜伏期延迟的研究一致，并且表明ASD儿童和ND儿童存在不同的成熟模式。需要进行纵向研究来确认这两组儿童的AEF潜伏期是否从大约3岁开始随年龄出现差异。
