Brain Activity and Language Comprehension in Psychosis

描述：（由申请人提供）思维障碍是一种主要症状， 精神分裂症，并通过异常语言推断。底层 导致思维障碍的认知异常是未知的。的总体目标 这个建议是为了了解思维障碍的神经生理学基础 精神分裂症和精神病躁狂症我们将测试语义模型 精神分裂症患者的过度激活和言语工作记忆功能障碍， 与躁狂症的执行注意力异常形成对比。我们将测量 语言理解，反应时间和大脑的活动， 事件相关电位，并将这些措施与临床措施相关联 症状和工作记忆表现的神经心理学测量。一 可能的功能障碍是语义记忆激活的异常 （hyperpriming），通过上下文不适当的概念， 精神分裂症患者的心理奇怪的是，精神分裂症患者 在快速词汇判断任务中的表现优于对照组，反应更快 次然而，在较慢的速度下，患者的表现福尔斯下降 大幅这种超启动和后来的下降的神经基质 性能是未知的。我们测试了一个精神分裂症思维的双因素模型 一种既有最初的自动兴奋异常，又有后来的自动兴奋异常的疾病 语言运用中对语境的控制性运用的异常 通过让受试者处理句子、单词对和单词三联体来记忆， 语义相关性刺激将包括同形异义词作为主要探针 联想紊乱 同形异义词是具有多重意义的词，在多个词中占有一席之地 无关语义网络例如，董事会可能意味着木板或委员会。 精神分裂症患者似乎表现出语义偏向强 他们倾向于选择占主导地位的同形异义词 即使面对要求访问的上下文， 董事会的意思是委员会（Board means committee）。我们建议研究语言 在改变网络强度的同时进行处理（主导与从属 意义），而变化的关联强度（强与弱 关联词），在面对强偏见的背景下，其次是弱 联想，并在面对弱偏见的背景下，其次是强 合伙人这些不同的操作将在快速（250 毫秒）和慢（1.25秒）速率，以更重地强调语义激活 系统和言语工作记忆系统。 ERP的使用允许刺激处理的直接测量，并提供 关于脑功能障碍的假定来源的一些信息（当被告知 从以前的直接记录）。这些研究有可能帮助 阐明精神分裂症和精神病患者认知功能障碍的性质 狂躁症。

DESCRIPTION: (provided by applicant) Thought disorder is a cardinal symptom of schizophrenia, and is inferred through abnormal language. The underlying cognitive abnormality that causes thought disorder is unknown. The broad aim of this proposal is to understand the neurophysiological basis of thought disorder in schizophrenia and psychotic mania. We will test a model of semantic over-activation and verbal Working memory dysfunction in schizophrenia, contrasted with an executive attention abnormality in mania. We will measure language comprehension, reaction times, and the activity of the brain via event-related potentials, and correlate these measures with clinical measures of symptoms and neuropsychological measures of working memory performance. One possible dysfunction is an abnormality in semantic memory activation (hyperpriming) whereby associated by contextually inappropriate concepts crowd the mind of schizophrenia patients. Paradoxically, schizophrenia patients outperform controls on speeded lexical decision tasks, with faster reaction times. However, at slower speeds, the performance of patients falls off sharply. The neural substrates of this hyperpriming and of the later drop off in performance are unknown. We test a two-factor model of schizophrenic thought disorder with both an initial automatic excitatory abnormality and a later abnormality in the controlled utilization of context stored in verbal working memory by having subjects process sentences, word pairs, and word triplets for semantic relatedness. The stimuli will include homographs as the primary probe of associative derangement. Homographs are words with multiple meanings, and occupy places in more than one unrelated semantic network. For example, board may mean plank or committee. Schizophrenia patients appear to display a semantic bias towards strong associates and networks such that they tend to select the dominant homograph meaning (board means plank) even in the face of context that mandates accessing the subordinate meaning (board means committee). We propose to examine language processing while varying networks strength (dominant versus subordinate meanings), while varying associative strength (strongly versus weakly associated words), in the face of strongly biasing context followed by weak associates, and in the face of weakly biasing context followed by strong associates. These different manipulations will be presented under fast (250 msec) and slow (1.25 sec) rates, to more heavily stress the semantic activation system and the verbal working memory system respectively. The use of ERPs allows for direct measures of stimulus processing, and provides some information about putative sources of brain dysfunction (when informed from previous direct recordings). These studies have the potential to help clarify the nature of cognitive dysfunction in schizophrenia and in psychotic mania.