Neurophysiological Studies of Visual Perception in Schizophrenia

精神分裂症视觉感知的神经生理学研究

• 批准号: 7686665
• 负责人: KEVIN M SPENCER
• 金额: --
• 依托单位: VA BOSTON HEALTH CARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2012-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7686665
• 关键词: Accounting; Affect; Area; Behavioral; Binding; Brain; Chronic Schizophrenia; Code; Cognitive; Disease; Electroencephalogram; Exhibits; Face; Failure; Family; Feedback; Frequencies; General Population; Goals; Hallucinations; Health Care Costs; Individual; Interneurons; Lead; Link; Measures; Mediating; Mentally Ill Persons; Mind; Neurons; Patients; Perception; Phase; Prefrontal Cortex; Process; Psyche structure; Psychophysiology; Reporting; Scalp structure; Schizophrenia; Series; Societies; Stimulus; Symptoms; Testing; Thinking; Visual Cortex; Visual Hallucination; Visual Perception; Work; base; functional group; neural circuit; neurophysiology; object perception; prevent; psychologic; public health relevance; relating to nervous system; research study; response

DESCRIPTION (provided by applicant): We propose to use measures of neural synchrony in the scalp-recorded electroencephalogram (EEG) to examine the functional integrity of the neural circuitry underlying visual perception in schizophrenia. Schizophrenia has been conceptualized as a failure of the integration of cognitive and neural processes, and abnormalities in neural circuitry (particularly inhibitory interneurons) have been proposed as a basis for this disorder. A growing number of studies have reported that individuals with schizophrenia demonstrate abnormal synchronization in the gamma (3) band of the EEG (30-100 Hz). These 3 oscillations have been proposed to mediate perceptual and cognitive processes by dynamically linking together neurons into functional groups, and are known to critically rely upon the same types of inhibitory interneurons as are disturbed in schizophrenia. Therefore, abnormalities in 3 oscillations in schizophrenia patients may reflect neural circuit abnormalities at the core of this disorder. In previous work we have found that a particular 3 oscillation, the response-locked oscillation (RLO), is sensitive to core symptoms of schizophrenia. In healthy individuals, 3-band RLOs over distinct areas of visual cortex are elicited by objects formed by both real and illusory contours, while an RLO over the prefrontal cortex is elicited by both types of objects. In chronic schizophrenia patients, the occipital RLO elicited by illusory objects exhibits 2 abnormalities: 1) the frequency is reduced from the 3 to the beta (2) band (13-30 Hz); and 2) the degree of phase-locking of this oscillation is positively correlated with thought disorder and disorganization symptom measures, as well as visual hallucinations. These findings converge with psychophysical studies of Gestalt perception, which have found that abnormalities of perceptual integration in schizophrenia-spectrum disorders are related to disorganization and thought disorder. Furthermore, other studies of 3 oscillations in schizophrenia have also found positive correlations between hallucination symptoms and 3 phase synchrony. These findings lead to 2 hypotheses: 1) the occipital RLO reflects a synchrony-based mechanism that is closely involved in perceptual feature-binding, and is sensitive to both primary neural circuitry abnormalities and core symptoms in schizophrenia; and 2) the positive correlations between RLO phase locking and positive symptoms reflect a propensity for neural circuits to synchronize inappropriately in schizophrenia. This project will test these hypotheses in a series of experiments examining chronic schizophrenia patients (SZ) and matched healthy control subjects (HC). Our specific aims are to: 1) extend the findings of RLO abnormalities to a broader range of Gestalt processes; 2) investigate the basis of the neural circuit abnormality that causes the RLO to occur at a lower frequency in SZ than HC; 3) connect the behavioral abnormalities of Gestalt perception that are associated with disorganization symptomatology and the occipital RLO, which shows correlations with disorganization symptoms. PUBLIC HEALTH RELEVANCE: Schizophrenia affects approximately 1% of the general population and has profound negative consequences for the personal, psychological, and fiscal well being of patients, their families, and society as a whole. This disorder characterizes a major group of patients in the VHA, where the chronically mentally ill (primarily patients with schizophrenia) account for a large proportion of VA mental healthcare costs. To treat and ultimately prevent schizophrenia, we must understand how the mind and brain are interrelated. This project seeks to further this goal by studying how brainwave synchronization is related to perception and thinking in people who are healthy, and in people who have schizophrenia.

描述(由申请人提供)： 我们建议在头皮记录的脑电(EEG)中使用神经同步性的测量来检查精神分裂症患者潜在视觉知觉的神经回路的功能完整性。精神分裂症被认为是一种认知和神经过程整合的失败，神经回路(特别是抑制性中间神经元)的异常被认为是这种疾病的基础。越来越多的研究报告说，精神分裂症患者在脑电(30-100赫兹)的伽马(3)频段表现出异常的同步性。这三种振荡被认为通过将神经元动态连接成功能群来调节知觉和认知过程，并已知严重依赖于精神分裂症中受到干扰的相同类型的抑制性中间神经元。因此，精神分裂症患者3个振荡的异常可能反映了这种疾病的核心神经回路异常。在以前的工作中，我们已经发现一种特殊的3振荡，即反应锁定振荡(RLO)，对精神分裂症的核心症状敏感。在健康个体中，视皮层不同区域上的3波段RLO由真实和虚幻轮廓形成的物体引起，而前额叶皮质上的RLO由两种类型的物体引起。在慢性精神分裂症患者中，幻觉物体引起的枕叶RLO表现出两种异常：1)频率从3频段降低到β(2)频段(13-30赫兹)；2)这种振荡的锁相程度与思维障碍和混乱症状以及视觉幻觉的程度呈正相关。这些发现与格式塔知觉的心理物理学研究相一致，这些研究发现，精神分裂症谱系障碍中的知觉整合异常与组织混乱和思维障碍有关。此外，其他对精神分裂症3次振荡的研究也发现幻觉症状与3相同步之间存在正相关。这些发现导致了两个假设：1)枕叶RLO反映了一种基于同步的机制，与知觉特征绑定密切相关，对精神分裂症的初级神经回路异常和核心症状都很敏感；2)RLO相位锁定与阳性症状之间的正相关反映了精神分裂症神经回路不适当同步的倾向。该项目将对慢性精神分裂症患者(SZ)和匹配的健康对照受试者(HC)进行一系列实验，以检验这些假设。我们的具体目标是：1)将RLO异常的发现扩展到更广泛的格式塔突起；2)调查导致SZ的RLO发生频率低于HC的神经回路异常的基础；3)将与组织紊乱症状相关的格式塔知觉行为异常与枕骨RLO联系起来，后者与组织紊乱症状相关。 公共卫生相关性： 精神分裂症影响大约1%的总人口，并对患者、他们的家人和整个社会的个人、心理和经济健康产生深远的负面影响。这种障碍是VHA中的一个主要患者群体的特征，在VHA中，慢性精神病患者(主要是精神分裂症患者)占退伍军人管理局精神卫生保健费用的很大比例。为了治疗并最终预防精神分裂症，我们必须了解大脑和大脑是如何相互联系的。这个项目试图通过研究脑波同步如何与健康人和精神分裂症患者的知觉和思维有关来进一步实现这一目标。