Over the last decade the combination of brain neuroimaging techniques and graph theoretical analysis of the complex anatomical and functional networks in the brain have provided an exciting new platform for exploring the etiology of mental disorders such as schizophrenia. This review introduces the current status of this work, focusing on the topological properties of human brain networks - called 'small-world brain networks'- and on the disruptions in these networks in schizophrenia. The evidence supporting the findings of reduced efficiency of information exchange in schizophrenia both within local brain regions and globally throughout the brain is reviewed and the potential relationship of these changes to cognitive and clinical symptoms is discussed. Finally we propose some suggestions for future research.
目的采用优化的基于体素的形态学(voxel based morphometry,VBM)方法,比较偏执型精神分裂症、双相情感障碍躁狂患者脑灰质体积的差异。方法运用3.0T磁共振扫描仪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20例偏执型精神分裂症住院患者、20例双相情感障碍躁狂相住院患者和20例正常对照进行3D T1像扫描。在SPM2平台上,以优化的VBM方法对高分辨T1加权图像进行处理,比较上述研究对象脑灰质体积的差异。结果与正常对照比较,偏执型精神分裂症患者右侧颞中回、颞下回,左侧颞上回灰质体积减少,而双侧额下回、双侧屏状核灰质体积增加。双相情感障碍躁狂患者与正常对照比较出现灰质体积减少的脑区包括双侧尾状核,右侧颞叶颞上、中、下回,灰质体积增加的脑区包括左侧顶叶中央后回、双侧楔前叶、右侧额上回、左侧扣带回。偏执型精神分裂症患者与双相情感障碍躁狂患者相比左侧颞上回、左侧额下回、右侧尾状核体灰质体积增加。结论偏执型精神分裂症患者与双相情感障碍躁狂患者既存在不同脑区的灰质体积的改变,也存在共同的右侧颞叶灰质体积改变。
目的探讨首发精神分裂症患者脑代谢物非对称性的改变及其受非典型抗精神病药物治疗的影响。方法对符合美国精神障碍诊断与统计手册第4版(Diagnostic and Statistical Manual of Mental Disorders,DSM-Ⅳ)诊断标准的21例首发精神分裂症患者和21名健康对照进行氢质子磁共振波谱扫描,并在治疗1年后对患者再次进行扫描,检测双侧额叶白质和海马的N-乙酰天门冬氨酸(N-Acetylaspartate,NAA)、胆碱(choline,Cho)和肌酸(creatine,Cr),以Cr为参照物,分别计算双侧NAA/Cr、Cho/Cr比值。在治疗前后对患者进行阳性和阴性量表(positive and negcotive symtoms scale,PANSS)、大体功能量表(global assessment function,GAF)评定。采用配对t检验进行脑代谢物非对称性分析。结果非对称性分析发现基线期健康对照组左侧海马NAA/Cr比右侧高[(1.41±0.09)vs.(1.32±0.10),P<0.05],首发精神分裂症组左、右侧海马代谢物比较,差异无统计学意义;而经过1年治疗后,与治疗前相比首发精神分裂症组PANSS评分显著降低(68.57±27.74vs.97.95±13.81)、GAF量表评分显著增加(58.76±23.07 vs.28.05±8.99),均P<0.05,精神分裂症组左侧海马NAA/Cr比右侧高[(1.41±0.10)vs.(1.31±0.13),P<0.05]。健康对照组及首发精神分裂症组治疗前后双侧额叶白质代谢物差异均无统计学意义(P>0.05)。结论首发精神分裂症患者海马NAA/Cr的非对称性消失,经非典型抗精神病药物治疗后,在精神症状改善的同时海马NAA/Cr的非对称性恢复。