聋儿耳蜗植入后大脑功能网络连接与中枢听处理变化机制研究

More research needs to be done to understand the tremendous individual variability seen in children with cochlear implants. The central auditory development and plasticity is regarded as the key reason. Previous reports and our studies show that the peak and latency of the P1, mismatch negativity component of the cortical auditory evoked potential provide insight into the development of the auditory cortex in deaf children fitted with cochlear implants. But the waveform analysis could not well reflect the specific area of auditory processing and the correlation with other brain regions, thus could not explain that part of the children with good waveform response but not ideal CI outcomes. The above phenomenon may be explained by the overall development of functional interaction and (or) the local development of the functional region. And our preliminary study shows both contribute to CI outcome. Based on the existing research, and combined with network connections and location technology of brain functions, the study will further explore changes in brain function mechanism for dealing with network connections and central hearing after cochlear implants for deaf children, and to explore its underlying neural mechanisms of auditory reconstruction. At the same time by comparing the different CI outcomes, we want to clear the factors of CI rehabilitation, and to provide better method and theory for the rehabilitation intervention.

聋儿人工耳蜗（CI）术后听觉康复效果个体差别大，目前认为关键在于CI术后听觉中枢的发育与重塑。既往报道及我们的前期研究显示听觉事件相关电位成分P1、失匹配负波等的潜伏期与波幅与听觉发育相关，在一定程度反映听觉重建后的听觉中枢发育情况，但不能很好反映听觉中枢处理位置特征及与其他大脑区域的相关关系，也无法解释部分CI患儿脑电成分反应好但听觉行为不理想的现象。上述现象可能与大脑的整体功能交互的成熟和（或）功能区域的发育机制有关。我们的初步研究显示CI术后听觉康复程度与功能网络的成熟及功能区域的位置与强度均相关。本研究拟在原有研究的基础上结合脑功能网络连接计算及脑功能定位技术进一步探索聋儿CI后听觉重建过程大脑功能网络变化及听觉中枢的功能处理变化机制，深入探索听觉中枢重塑神经机制。同时通过对比聋儿听觉康复效果，明确影响CI术听觉康复的因素，为听觉康复的干预提供更好的理论与思路。

聋儿人工耳蜗（CI）术后听觉的发育与大脑的整体功能交互的成熟和功能区域的发育相关。本研究拟结合脑功能网络连接计算及脑功能定位技术探索聋儿CI术后听觉重建过程大脑功能网络变化及听觉中枢的功能处理变化机制，深入探索听觉中枢重塑神经机制。同时通过对比聋儿听觉康复效果，明确影响CI术听觉康复的因素，为听觉康复的干预提供更好的理论与思路。我们的结果显示患儿的听觉刺激脑功能网络呈聚系数分布呈小世界特征，神经网络的成熟与听觉功能的康复有密切相关。同时，CI术后大脑相关区域功能能量变化也与CI使用时间相关，CI术后6个月内，大部分的相关区域在刺激下能量均有增强，在6个月达到高峰后下降。另外，视听功能网络连接有特征性变化，CI术后3个月组平均听区/视区modality值之比（A/V）比值先上升后下降，至术后12个月时接近对照。在此基础上，我们进一步发现CI术后患儿康复效果与视觉诱发ERP的颞顶区N1波幅相关，且利用“有声”图片更易呈现这种相关性。聋儿听觉中枢的可塑程度与CI术后言语康复呈正相关，并且视－听联合处理功能的提高也可能促进听觉的康复。更进一步的，我们发现语前聋患儿人工耳蜗植入后视觉皮层出现重塑，表现为视觉诱发皮层反应中的P2潜伏期随着耳蜗使用时间逐渐缩短。P2潜伏期可能是语前聋患儿人工耳蜗植入后视觉皮层重塑的电生理指标。并且，视觉可引起过度的关注而影响听觉康复。另外，不同参考电极对人工耳蜗术后患者听觉ERP结果分析有影响，对于CI的患儿，我们推荐使用对侧乳突作为人工耳蜗ERP研究中的参考电极。