An investigation on the neural network for impaired articulation using non-invasive functional brain imaging

用于语音的神经网络可以细分为两个阶段，如想象阶段和执行阶段，这些阶段的产物分别被称为隐性语音和显性语音。另一方面，唇腭裂(CLP)的受试者会表现出言语障碍或代偿性发音障碍。以前的研究表明，患有CLP和不患有CLP的受试者之间的显著差异在于：1)发音过程中大脑的激活模式(Shinagawa，et al.，2006)，以及2)发音器的运动模式(Sato-Wakabayashi，et al.，2008)。然而，中电组和非中电组之间发音差异的原因尚不清楚。受试者为单侧(UCLP)、双侧(BCLP)L患者和无CLP患者。我们使用的是1.5T磁共振设备。受试者以1.5赫兹的频率重复/ka/，以区块设计中的隐蔽(C)或显性(O)言语进行分析，同时采集功能MRI数据。结果表明，在有无CLP的受试者中，C语言时前运动区被激活。在O语音过程中，UCLP组和非CLP组的运动前区、初级运动皮质和小脑均被激活。另一方面，在患有BCLP的患者中，这些区域没有被激活，但扣带回的后部被激活。这些发现表明，在想象阶段似乎没有什么不同，但在执行阶段的发音在有无CLP的受试者之间存在差异。这些差异可能与多种因素有关，包括唇裂的类型、运动输出和感觉输入的差异、发音障碍的类型和严重程度以及语音治疗的时机和效果。

Neural networks for speech may be subdivided into two stages, such as the imaginary and executive stages, and products from these stages are called covert and overt speech, respectively. On the other hand, subjects with cleft lip and palate (CLP) axe known to show impaired speech, or compensatory misarticulation. Previous studies showed that these were significant differences between subjects with and without CLP in 1) the activated pattern in the brain during articulation (Shinagawa, et al., 2006), and 2) the movement pattern of the articulators (Sato-Wakabayashi, et al., 2008). However, the responsible stage for the difference in articulation between those with and without CLP was unknown. Adult subjects with [unilateral (UCLP) and bilateral (BCLP)l and without CLP were recruited. We used a 1.5 T MR apparatus. Functional MRI data were taken while the subject repeated the velar plosive, /ka/, at 1.5 Hz for either covert (C) or overt (O) speech in the block design SPM2 was used for analysis. It was shown that the premotor area was activated during C speech in subjects with and without CLP. During O speech, the premotor area, the primary motor cortex and the cerebellum were activated in subjects with UCLP and those without CLP,. On the other hand, these areas were not activated but the posterior cingulate gyrus was activated in the subject with BCLP. These findings suggest that there seems to be little difference in the imaginary stage, but there are differences in the executive stage for articulation between subjects with and without CLP. It appears that several factors including types of the cleft, the difference in the motor outputs and sensory inputs, the types and severity of misarticulation and the timing and effect of speech therapy maybe involved in the difference.