Hemispheric Asymmetry of Endogenous Neural Oscillations in Young Children: Implications for Hearing Speech In Noise.
Hemispheric Asymmetry of Endogenous Neural Oscillations in Young Children: Implications for Hearing Speech In Noise.
复制标题
幼儿内源性神经振荡的半球不对称：对噪声中听力言语的影响。
DOI：
10.1038/srep19737
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发表时间：
2016
影响因子：
4.6
通讯作者：
Kraus,Nina
中科院分区：
文献类型：
--
作者：
Thompson,ElaineC;WoodruffCarr,Kali;White-Schwoch,Travis;Tierney,Adam;Nicol,Trent;Kraus,Nina
语音信号包含分级时间尺度中的信息，范围从短持续时间（例如，音素）到长持续时间提示（例如，音节，韵律）。理解大脑如何处理这种层次结构的理论框架表明，半球侧化能够在不同的时间尺度上专门跟踪声学线索，左半球和右半球分别在短（25 ms; 40 Hz）和长（200 ms; 5 Hz）周期采样。在成年人中，语音诱发和内源性皮质节律都是不对称的：低频节律在右侧听觉皮质占主导地位，而高频节律在左侧听觉皮质占主导地位。然而，目前还不清楚内源性静息态振荡是否在儿童中也同样偏侧化。我们研究了儿童（3-5岁; N = 65）在休息时的皮层振荡，并测试了我们的假设，即这种时间不对称性在生命早期是明显的，有利于在噪音中识别语音。我们发现了一个系统的模式，增加更高频率的振荡的不对称性，这种模式是更明显的儿童谁更好地感知噪音的话。左偏皮质振荡音素相关的频率和语音噪声感知之间的联系表明，半球的内源性振荡活动的专业化可能支持语音处理在具有挑战性的听力环境，这种基础设施是存在于幼儿期。
Speech signals contain information in hierarchical time scales, ranging from short-duration (e.g., phonemes) to long-duration cues (e.g., syllables, prosody). A theoretical framework to understand how the brain processes this hierarchy suggests that hemispheric lateralization enables specialized tracking of acoustic cues at different time scales, with the left and right hemispheres sampling at short (25 ms; 40 Hz) and long (200 ms; 5 Hz) periods, respectively. In adults, both speech-evoked and endogenous cortical rhythms are asymmetrical: low-frequency rhythms predominate in right auditory cortex and high-frequency rhythms in left auditory cortex. It is unknown, however, whether endogenous resting state oscillations are similarly lateralized in children. We investigated cortical oscillations in children (3–5 years; N = 65) at rest and tested our hypotheses that this temporal asymmetry is evident early in life and facilitates recognition of speech in noise. We found a systematic pattern of increasing leftward asymmetry for higher frequency oscillations; this pattern was more pronounced in children who better perceived words in noise. The observed connection between left-biased cortical oscillations in phoneme-relevant frequencies and speech-in-noise perception suggests hemispheric specialization of endogenous oscillatory activity may support speech processing in challenging listening environments and that this infrastructure is present during early childhood.