精神分裂症听觉信息整合功能异常的电生理研究

Auditory information integration defect is one of the important dysfunction in schizophrenia. Auditory information in both ears may exist tiny differences, integrating binaural information is a key step of recognizing and further processing auditory content. Losses in functions of binaural information integration will distort recognizing auditory target, affect higher-level cognition and may be related with negative symptoms and even psychotic symptoms such as auditory hallucination. Electrophysiology technology has the time resolution of milliseconds and is capable of separating the integration of binaural information and detecting the degrees of abnormalities in perceptual integration function. This study focuses on the integration ability of auditory information from both ears, utilizing a discrimination task on the interaural uncorrelated information and electrophysiology technology. According to the specific features of strength and synchronization of electrophysiological activities in auditory information integration, electrophysiological indices that are sensitive to losses in auditory information integration abilities are extracted. The complementary information among electrophysiological indices help build multivariate statistical analysis models that could comprehensively describe relationships between the severity schizophrenic patients and levels of auditory information integration and help verify the effectiveness of model in discriminating schizophrenic and healthy controls. It is thus of great importance for the early recognition of schizophrenia in investigating the abnormalities in auditory information integration mechanism and exploring sensitive and stable electrophysiological indices.

听觉信息整合功能异常是精神分裂症重要功能障碍之一。双耳听觉内容通常存在细微差别，将双耳信息加以整合是听觉内容识别和深入加工的基础环节。双耳信息整合功能出现缺损，将干扰听觉目标的识别，直接影响认知功能，与阴性症状甚至幻听等精神病性症状存在关联。电生理技术具有毫秒级的时间分辨率，能够分离出听觉信息的整合过程，从而有效测查双耳听觉信息整合功能异常的程度。本项目利用左右耳不相干信息的辨别任务，结合电生理技术考察首发未用药精神分裂症患者和健康对照的信息整合能力差异。针对听觉信息整合阶段电生理活动强度和同步性等不同方面的特征，提炼对整合功能损伤程度敏感的电生理指标。然后建立多元统计分析模型，充分利用各项指标之间的互补信息，全面考察疾病严重程度与听觉整合功能水平的关系，并验证模型用于区分患者和健康对照的判别效果。深入探索听觉信息整合机制异常，寻找敏感稳定的电生理指标，对于精神分裂症早期识别具有重要意义。

精神分裂症感知觉功能异常是重要临床表现之一，其中可能与幻觉、妄想、偏执等核心症状存在密切关联。本研究以听觉功能为例，选择双耳整合功能，配合听觉匹配、听觉震荡能力，研究精神分裂症听觉加工缺陷，比较首次发作患者、慢性患者和健康对照之间听觉加工缺陷，验证双耳整合能力差异，形成成套的听觉能力测查工具。此外，针对精神分裂症听觉加工缺陷的神经病理机制进行深入探讨，采用神经电生理技术，系统研究精神分裂症患者和健康对照人群在静息状态、听觉任务状态中神经电生理节律能量、皮层不对称性、事件相关电位P1、N1幅值和潜伏期差异。研究结果发现，精神分裂症患者固定双耳不相关片段长度条件下，可探测的延时阈值显著短于健康对照组，固定延迟时间条件下，可探测的片段长度也显著长于健康对照；提示精神分裂症患者双耳整合能力存在明显缺陷，无法对左右耳同一声源的声音内容进行有效整合，增加了知觉负载，影响了知觉体验，妨碍了后续目标物体的形成乃至决策判断。本研究还利用神经电生理技术对双耳整合能力进行了深入探讨，发现其与听觉匹配能力（MMN）和听觉震荡（ASSR）等神经电生理指标存在关联，且精神分裂症患者与健康对照组之间在电生理指标上存在显著差异。研究显示，双耳听觉系列指标用于疾病鉴别诊断具有较大区分效度度（Cohen’d=0.9648），且无论双耳整合行为学测查还是电生理指标，均有发现与精神分裂症临床症状评分条目存在显著相关，可为客观评估精神分裂症脑功能异常提供行为学和电生理学指标。