Spectral-temporal EEG dynamics of speech discrimination processing in infants during sleep
Spectral-temporal EEG dynamics of speech discrimination processing in infants during sleep
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DOI：
10.1186/s12868-017-0353-4
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发表时间：
2017-03-22
期刊：
影响因子：
2.4
通讯作者：
Yoshinaga-Itano, Christine
中科院分区：
文献类型：
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作者：
Gilley, Phillip M.;Uhler, Kristin;Yoshinaga-Itano, Christine
背景资料：Oddball范式经常被用来研究听觉辨别，通过比较事件相关电位（ERP）的反应，从一个标准的，高概率的声音和一个偏差，低概率的声音。以前的研究已经确定，这种范式，如不匹配的反应或不匹配的负性，是有用的检查幼儿和婴儿在各种睡眠和注意力状态的听觉过程。在何种程度上古怪的ERP反应可能反映微妙的歧视效果，如语音歧视，在很大程度上是未知的，特别是在婴儿尚未获得语音和language.Results：三个对比（非语音，元音和辅音）的不匹配响应计算作为一个频谱时间的概率函数在24个婴儿，并在组水平上分析了修改后的多维尺度。在γ响应（30-50 Hz）开始后，β振荡（12-30 Hz）的出现与较低频率的θ振荡（2-8 Hz）在时间上耦合。这种耦合效应相对于随后的θ调制的频谱-时间概率对应于非语音，元音和辅音对比features.Discussion的歧视困难：θ调制效应表明，意想不到的声音被编码为惊喜的概率测量。这些结果支持了这样一种观点，即听觉辨别力是由大脑预测处理网络的发展驱动的，并且可以在婴儿睡眠期间进行测量。这里提出的结果有影响的解释歧视作为一个概率的过程，并可能提供一个基础的发展，在临床上有用的context.Conclusion：一个婴儿的大脑处理信息的环境和执行计算，即使在睡眠中的单一主题和单一的审判分类。这些计算反映了语言学习所必需的声学特征处理的细微差异。这项研究的结果表明，在一个古怪的范例异常声音的大脑反应遵循振荡调制级联。该级联以伽马响应开始，该伽马响应随后作为β同步出现，该β同步在时间上与θ调制耦合，并且随后是第二个后续θ调制。θ调制的频率和时间的差异似乎反映了一种惊讶的程度。这些见解听觉歧视的神经生理机制提供了一个基础，探索临床实用的MMRTF和其他听觉oddball反应。
Background: Oddball paradigms are frequently used to study auditory discrimination by comparing event-related potential (ERP) responses from a standard, high probability sound and to a deviant, low probability sound. Previous research has established that such paradigms, such as the mismatch response or mismatch negativity, are useful for examining auditory processes in young children and infants across various sleep and attention states. The extent to which oddball ERP responses may reflect subtle discrimination effects, such as speech discrimination, is largely unknown, especially in infants that have not yet acquired speech and language.Results: Mismatch responses for three contrasts (non-speech, vowel, and consonant) were computed as a spectral-temporal probability function in 24 infants, and analyzed at the group level by a modified multidimensional scaling. Immediately following an onset gamma response (30-50 Hz), the emergence of a beta oscillation (12-30 Hz) was temporally coupled with a lower frequency theta oscillation (2-8 Hz). The spectral-temporal probability of this coupling effect relative to a subsequent theta modulation corresponds with discrimination difficulty for non-speech, vowel, and consonant contrast features.Discussion: The theta modulation effect suggests that unexpected sounds are encoded as a probabilistic measure of surprise. These results support the notion that auditory discrimination is driven by the development of brain networks for predictive processing, and can be measured in infants during sleep. The results presented here have implications for the interpretation of discrimination as a probabilistic process, and may provide a basis for the development of single-subject and single-trial classification in a clinically useful context.Conclusion: An infant's brain is processing information about the environment and performing computations, even during sleep. These computations reflect subtle differences in acoustic feature processing that are necessary for language-learning. Results from this study suggest that brain responses to deviant sounds in an oddball paradigm follow a cascade of oscillatory modulations. This cascade begins with a gamma response that later emerges as a beta synchronization, which is temporally coupled with a theta modulation, and followed by a second, subsequent theta modulation. The difference in frequency and timing of the theta modulations appears to reflect a measure of surprise. These insights into the neurophysiological mechanisms of auditory discrimination provide a basis for exploring the clinically utility of the MMRTF and other auditory oddball responses.