An fMRI study investigating effects of conceptually related sentences on the perception of degraded speech.
An fMRI study investigating effects of conceptually related sentences on the perception of degraded speech.
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DOI：
10.1016/j.cortex.2016.03.014
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发表时间：
2016-06
期刊：
影响因子：
--
通讯作者：
Blumstein SE
中科院分区：
文献类型：
--
作者：
Guediche S;Reilly M;Santiago C;Laurent P;Blumstein SE
先前的研究表明，退化语音的感知受到句子内意义的影响，并招募了一个或多个组成部分的额颞顶叶网络。本研究的目的是检验由一组词组成的句子的整体概念意义是否会影响由另一组词组成的第二个声学退化句子的感知。使用功能磁共振成像（fMRI），我们提出了一个声学清晰的句子，然后是一个声学退化的句子，并操纵它们之间的语义关系：相关的意义（但由不同的内容词组成），无关的意义，或相同。结果表明，当目标句前面有一个概念相关的句子时，听者对声学退化句子的单词识别准确率显着高于一个概念无关的句子。对概念关系的敏感性与中、下额叶、颞叶和顶叶区域的活动增强有关。此外，左侧额中回（LMFG）、左侧额下回（LIFG）和左侧颞中回（LMTG）的活动与相关条件下的个体表现相关。上级颞回（STG）在相同条件下激活增加，表明它对感知相似性敏感，而不是句子对之间的意义整合。额颞顶叶网络似乎巩固跨语言（声学，词汇，句法，语义）的多个层次的信息源，以建立，并最终整合跨句子的概念信息，并促进对退化的语音信号的感知。然而，可用信息来源的性质不同，招募特定区域并调节其在该网络中的活动。这些发现的网络的功能架构的影响被认为是。
Prior research has shown that the perception of degraded speech is influenced by within sentence meaning and recruits one or more components of a frontal–temporal–parietal network. The goal of the current study is to examine whether the overall conceptual meaning of a sentence, made up of one set of words, influences the perception of a second acoustically degraded sentence, made up of a different set of words. Using functional magnetic resonance imaging (fMRI), we presented an acoustically clear sentence followed by an acoustically degraded sentence and manipulated the semantic relationship between them: Related in meaning (but consisting of different content words), Unrelated in meaning, or Same. Results showed that listeners' word recognition accuracy for the acoustically degraded sentences was significantly higher when the target sentence was preceded by a conceptually related compared to a conceptually unrelated sentence. Sensitivity to conceptual relationships was associated with enhanced activity in middle and inferior frontal, temporal, and parietal areas. In addition, the left middle frontal gyrus (LMFG), left inferior frontal gyrus (LIFG), and left middle temporal gyrus (LMTG) showed activity that correlated with individual performance on the Related condition. The superior temporal gyrus (STG) showed increased activation in the Same condition suggesting that it is sensitive to perceptual similarity rather than the integration of meaning between the sentence pairs. A fronto-temporo-parietal network appears to consolidate information sources across multiple levels of language (acoustic, lexical, syntactic, semantic) to build, and ultimately integrate conceptual information across sentences and facilitate the perception of a degraded speech signal. However, the nature of the sources of information that are available differentially recruit specific regions and modulate their activity within this network. Implications of these findings for the functional architecture of the network are considered.