Auditory-verbal functional studies of schizophrenia

描述（由申请人提供）：本提案将使用功能性磁共振成像（fMRI）评估早期听觉处理、言语语义处理及其与首次发作（FE）、慢性精神分裂症（CSZ）和匹配对照受试者（CN）阳性症状的相关性。这些研究旨在了解脑功能障碍与症状之间的联系，从而促进预防措施和治疗方法的发现。上级颞回（STG）在听觉言语知觉和语言加工中起着重要作用。在精神分裂症受试者（SZ）的MRI研究中，该区域一直报告显示体积减小。这些音量减少与幻听，思维障碍和听觉事件相关电位（ERP）异常有关。左STG异常也一贯显示在功能成像研究的主动幻觉或言语加工的SZ。在慢性SZ的STG异常fMRI活动被发现使用失配负性（MMN）刺激，这是类似于ERP范式中使用的。最近的发现已经记录了正常个体语言侧化基础的结构和功能证据。我们将使用这些最新的发现，在一个快速的声学处理任务（RAP），除了MMN任务，作为一个基础上提出的研究检查早期的听觉处理在深圳。颞叶外侧区（中、下）和颞顶区被认为在语义加工中发挥作用。这些区域在使用语言的精神分裂症的功能成像和ERP研究中也显示出异常。语义启动已被证明（虽然不一致）在一些研究中是不正常的SZ。最近的一项行为研究使用了语义网络属性不同的单词。SZ被试的词线索回忆成绩下降归因于语义网络的异常连通性，而不是网络大小。SZ和CN受试者将在听觉/言语语义启动的fMRI研究中接受测试。本研究将探讨语义联想者之间的扩散激活相关的脑活动。单词的连接程度会有所不同，因此其关联词之间的激活扩散程度也会有所不同。最近完成的一项对CN受试者的初步研究使用了这种语义启动任务（SP），并发现正如预测的那样，颞叶区域的不同大脑活动模式与单词对的不同语义属性（连接性和相关性）相关。

DESCRIPTION (provided by applicant): This proposal will use functional magnetic resonance imaging (fMRI) to assess early auditory processing, verbal semantic processing, and their association with positive symptoms in first episode (FE), chronic schizophrenic (CSZ), and matched control subjects (CN). These studies are aimed at understanding the link between brain dysfunction and symptoms, thus facilitating the discovery of preventative measures and treatments. The superior temporal gyrus (STG) plays a major role in auditory speech perception and language processing. This region is consistently reported to show volume reductions in MRI studies of schizophrenic subjects (SZ). These volume reductions have been linked to auditory hallucinations, thought disorder, and auditory event-related potential (ERP) abnormalities. Left STG abnormalities are also consistently shown in functional imaging studies of active hallucination or of auditory-verbal processing in SZ. Abnormal fMRI activity in the STG in chronic SZ was found using mismatch negativity (MMN) stimuli that were similar to those used in an ERP paradigm. Recent discoveries have documented structural and functional evidence for the basis of language lateralization in normal individuals. We will use these recent discoveries, in a rapid acoustic processing task (RAP), in addition to the MMN task, as a basis for proposed studies examining early auditory processing in SZ. Lateral temporal (middle, inferior) and temporal-parietal regions are thought to play a role in semantic processing. These regions have also shown abnormalities in functional imaging and ERP studies of schizophrenia that use language. Semantic priming has been shown (although not consistently) in a number of studies to be abnormal in SZ. A recent behavioral study used words that differed in terms of the properties of their semantic networks. The reduced performance of SZ subjects on the cued recall of words was attributed to the effects of abnormal connectivity in the semantic network but not network size. SZ and CN subjects will be tested in an fMRI study of auditory/verbal semantic priming. This study will examine the brain activity related to the spreading activation between semantic associates. Words will vary in the degree of connectivity, and hence the degree of spreading activation between their associates. A recently completed preliminary study of CN subjects used this semantic priming task (SP) and found that as predicted, different patterns of brain activity in temporal lobe regions were associated with different semantic properties (connectivity and relatedness) of the word pairs.