Visual tuning and performance in schizophrenia and bipolar disorder

描述（由申请人提供）：精神分裂症（SZ）的视觉处理异常是普遍的，见于各种范例，并且通常幅度很大。尽管它们的信息价值，这些损伤已收到远远低于研究的关注与额叶和颞叶皮层系统的损伤。视觉加工范式通常具有良好的神经基础，并为研究SZ的神经功能提供了直接的方法。部分由于研究重点的减少，我们的知识存在根本性的差距。这样的差距之一是缺乏一个完整的理论，令人满意地解释了在视觉处理措施的范围内的调查结果的模式。第二，我们不知道视觉处理障碍在慢性精神疾病（包括SZ和双相情感障碍（BD））诊断中的程度。虽然在视觉处理异常已被发现在BD，很少有人试图检查性能在BD在视觉处理阶段的详细方式。目前的应用程序将测试一个核心过程的理论，可能有助于解释在SZ和BD中观察到的视觉处理障碍的范围。我们假设，我们实验室和其他实验室的一系列发现，可能最简单地解释为神经元对物体特征的调节异常（即，相对于视觉上相似的对象，神经元不太能够对优选的视觉对象产生特定的神经响应;称为“视觉调谐”）。对物体或物体特征的视觉处理发生在外侧枕叶复合体（LO）。虽然在BD的视觉处理异常的文献是小于在SZ，这样的损害已经found. The当前的应用程序将评估是否在BD也源于视觉调谐的问题。拟定的研究将招募90名SZ患者、90名BD患者和90名健康对照，这些患者将在关键人口统计学变量上进行组匹配。受试者将参与知觉表现、电生理（EEG）、认知和功能磁共振成像（fMRI）程序，以解决以下三个目标：1）使用专门的EEG和fMRI方法检查SZ的视觉神经调谐：2）使用专门的EEG和fMRI方法检查SZ、BD和健康对照之间的视觉神经调谐交叉诊断;以及3）检查SZ、BD和健康对照者的视觉调谐缺陷的含义，包括知觉、高级认知和功能。该研究计划与NIMH战略计划和NIMH研究领域标准项目的几个组成部分一致。从这项研究计划的结果将导致SZ和BD之间的视觉处理的相似性和差异的信息，以及在这些条件下的视觉处理障碍的潜在神经基板。视觉调节是可修改的，并且可以在人类和动物中进行可靠的评估，因此这些信息将对治疗开发产生影响。

DESCRIPTION (provided by applicant): Visual processing abnormalities in schizophrenia (SZ) are pervasive, seen in a variety of paradigms, and typically large in magnitude. Despite their informative value, these impairments have received far less research attention than impairments associated with frontal and temporal cortical systems. Visual processing paradigms often have well-established neural bases and provide a direct way to investigate neural functioning in SZ. Partly as a result of reduced research emphasis there are fundamental gaps in our knowledge. One such gap is the absence of an integrated theory that satisfactorily explains the patterns of findings across the range of visual processing measures. A second is that we do not know the degree to which visual processing impairment extends across diagnoses for chronic mental illness, including SZ and bipolar disorder (BD). Although abnormalities in visual processing have been found in BD, few attempts have been made to examine performance in BD in a detailed manner across visual processing stages. The current application will test a theory of a core process that might help explain the range of visual processing impairment observed in SZ and BD. We hypothesize that an array of findings from our laboratory, and others, might be explained most parsimoniously as an abnormality in the tuning of neurons for object features (i.e., neurons are less able to generate specific neural responses to preferred visual objects versus visually similar objects; referred to as "visual tuning"). Visual processing for objects or object features occurs in the lateral occipital complex (LO). Although the literature on visual processing abnormalities in BD is smaller than that in SZ, such impairments have been found. The current application will evaluate whether such deficits in BD also stem from problems in visual tuning. The proposed study will recruit 90 SZ patients, 90 BD patients and 90 healthy controls that will be group- matched on key demographic variables. The subjects will participate in perceptual performance, electrophysiological (EEG), cognition, and functional magnetic resonance imaging (fMRI) procedures to address the following three aims: 1) To examine visual neural tuning in SZ using specialized EEG and fMRI methods; 2) To examine visual neural tuning cross-diagnostically among SZ, BD, and healthy controls with specialized EEG and fMRI methods; and 3) To examine the implications of visual tuning deficits in SZ, BD, and healthy controls, including perception, higher-level cognition, and functioning. This program of research is consistent with several components of the NIMH Strategic Plan and the NIMH Research Domain Criteria project. Results from this research program will lead to information on the similarities and differences in visual processing between SZ and BD, and the underlying neural substrates of visual processing impairment in these conditions. Visual tuning is modifiable and can be reliably assessed in humans and animals, so this information will have implications for treatment development.