Functional connectivity studies of patients with auditory verbal hallucinations.
Functional connectivity studies of patients with auditory verbal hallucinations.
复制标题
DOI：
10.3389/fnhum.2012.00006
复制
发表时间：
2011-12-02
影响因子：
2.9
通讯作者：
Hampson M
中科院分区：
文献类型：
--
作者：
Hoffman RE;Hampson M
本文综述了利用功能磁共振成像（fMRI）数据对导致言语幻听（AVHs）的脑机制的功能连接（FC）研究。最初的FC研究利用在执行各种任务期间收集的功能磁共振成像数据，表明额颞叶断裂和/或源监测干扰。后来的FC研究利用了静息（无任务）fMRI数据。这些研究产生了一幅复杂的画面，涉及与AVHs相关的不同通路的断开和超连接。本文详细回顾了我们最近对房颤的FC研究结果。本研究提示，AVHs产生的核心机制并非单一途径，而是一个更为复杂的功能回路。该回路的组成部分包括韦尼克区及其右侧同系物、左侧额叶下皮层和壳核。值得注意的是，壳核似乎在自发语言的产生中起着关键作用，并决定听觉刺激是否被有意识地登记为感知。因此，精神分裂症患者将该区域与韦尼克种子区连接起来的过度功能协调可能会产生过多的潜在有意识的语言表征。在我们的模型中，皮质纹状体回路的另外两条腿（韦尼克区与左侧IFG，以及左侧IFG与壳核）中完整的FC似乎允许壳核和韦尼克区（精神分裂症普遍存在）之间的超连通性表达为有意识的语言幻觉。讨论了未来研究的建议，包括采用多种方法应用于同一受试者，以比较和对比不同的机制假设，利用脑电图更好地分析导致AVHs的神经同步的时间过程，以及确定可能反映不同机制的AVHs的经验亚型。
Functional connectivity (FC) studies of brain mechanisms leading to auditory verbal hallucinations (AVHs) utilizing functional magnetic resonance imaging (fMRI) data are reviewed. Initial FC studies utilized fMRI data collected during performance of various tasks, which suggested frontotemporal disconnection and/or source-monitoring disturbances. Later FC studies have utilized resting (no-task) fMRI data. These studies have produced a mixed picture of disconnection and hyperconnectivity involving different pathways associated with AVHs. Results of our most recent FC study of AVHs are reviewed in detail. This study suggests that the core mechanism producing AVHs involves not a single pathway, but a more complex functional loop. Components of this loop include Wernicke's area and its right homologue, the left inferior frontal cortex, and the putamen. It is noteworthy that the putamen appears to play a critical role in the generation of spontaneous language, and in determining whether auditory stimuli are registered consciously as percepts. Excessive functional coordination linking this region with the Wernicke's seed region in patients with schizophrenia could, therefore, generate an overabundance of potentially conscious language representations. In our model, intact FC in the other two legs of corticostriatal loop (Wernicke's with left IFG, and left IFG with putamen) appeared to allow hyperconnectivity linking the putamen and Wernicke's area (common to schizophrenia overall) to be expressed as conscious hallucinations of speech. Recommendations for future studies are discussed, including inclusion of multiple methodologies applied to the same subjects in order to compare and contrast different mechanistic hypotheses, utilizing EEG to better parse time-course of neural synchronization leading to AVHs, and ascertaining experiential subtypes of AVHs that may reflect distinct mechanisms.