精神分裂症与双相Ⅰ型躁狂患者默认网络的比较研究

目的 比较研究精神分裂症和双相Ⅰ型躁狂发作患者默认网络连接的异同.方法 对符合美国精神障碍诊断统计手册第4版（DSM-Ⅳ）诊断标准的22例精神分裂症患者、22例双相Ⅰ型躁狂发作患者和22名健康对照进行静息态功能磁共振扫描.采用种子点功能连接方法重建出三组被试的默认网络,并进行组间比较,同时对默认网络连接强度和临床量表分之间的关联进行分析.结果 （1）精神分裂症患者在大脑中线包括楔前叶和背内侧前额叶表现功能连接显著增加（校正后P＜0.05）;（2）双相Ⅰ型躁狂发作患者在内侧额叶、边缘系统包括海马和后扣带回等区域表现功能连接的显著降低（校正后P＜0.05）;（3）两组患者均表现楔前叶的连接增强和外侧颞叶的连接显著降低（校正后P＜0.05）;（4）楔前叶、后扣带回和背内侧前额叶的连接强度与阴性症状正相关（校正后P＜0.05）.结论 本研究发现精神分裂症患者和双相Ⅰ型躁狂发作患者表现部分重叠的默认网络异常模式,精神分裂症主要表现为中线结构功能连接增高,双相Ⅰ型躁狂发作主要表现为前额叶和边缘系统结构功能连接下降.

Comparative study on default mode network in schizophrenia and bipolar mania

Objective To explore the functional connectivity alterations in patients with schizophrenia and bipolar disorder.Methods Resting-state functional magnetic resonance imaging data were collected from 22 patients who meet the diagnosis criteria of bipolar mania in DSM-Ⅳ,22 patients who meet the diagnosis criteria of schizophrenia in DSM-Ⅳ and 22 normal controls.Default mode network was reconstructed using seed-based functional connectivity approach and comparison was done.The association of connectivity strength and clinical measures were also examined.Results （1） Compared to controls,patients with schizophrenia showed increased connectivity strength within the cortical midline structures including the dorsal medial prefrontal lobe and precuneus.（2） Patients with bipolar mania exhibited decreased connectivity strength within the limbic system,including the medial prefrontal cortex,hippocampus,and posterior cingulate cortex.（3） Both patient groups showed increased connectivity strength in precuneus and decreased connectivity strength in lateral temporal lobe.（4） The connectivity strength of dorsal medial prefrontal lobe and precuneus were positively correlated with negative symptoms in patients.Conclusion There are partly overlapped patterns of functional alteration in schizophrenia and bipolar disorder,and these patterns are associated with neuropathology of two diseases.Patients with schizophrenia show increased connectivity strength within the cortical midline structures,while patients with bipolar mania exhibit decreased connectivity strength within the prefrontal and limbic system.