PDF(Pubmed)
Abstract：
Deficit schizophrenia is a subtype of schizophrenia presenting primary and enduring negative symptoms (NS). Although one of the most updated hypotheses indicates a relationship between NS and impaired motivation, only a few studies have investigated abnormalities of motivational circuits in subjects with deficit schizophrenia (DS). Our aim was to investigate structural connectivity within motivational circuits in DS. We analyzed diffusion tensor imaging (DTI) data from 46 subjects with schizophrenia (SCZ) and 35 healthy controls (HCs). SCZ were classified as DS (n = 9) and non-deficit (NDS) (n = 37) using the Schedule for Deficit Syndrome. The connectivity index (CI) and the Fractional Anisotropy (FA) of the connections between selected brain areas involved in motivational circuits were examined. DS, as compared with NDS and HCs, showed increased CI between the right amygdala and dorsal anterior insular cortex and increased FA of the pathway connecting the left nucleus accumbens with the posterior insular cortex. Our results support previous evidence of distinct neurobiological alterations underlying different clinical subtypes of schizophrenia. DS, as compared with NDS and HCs, may present an altered pruning process (consistent with the hyperconnectivity) in cerebral regions involved in updating the stimulus value to guide goal-directed behavior.
摘要：
缺陷型精神分裂症是精神分裂症的一种亚型，表现出原发性和持久性阴性症状（NS）。尽管最新的假设之一表明NS与受损动机之间存在关系，只有少数研究调查了缺陷型精神分裂症（DS）受试者的动机回路异常。我们的目的是研究DS中动机回路内的结构连通性。我们分析了46名精神分裂症（SCZ）受试者和35名健康对照（HC）的扩散张量成像（DTI）数据。使用缺陷综合征时间表将SCZ分类为DS（n=9）和非缺陷（NDS）（n=37）。检查了参与动机回路的选定大脑区域之间的连接指数（CI）和分数各向异性（FA）。DS,与NDS和HC相比，显示右杏仁核和背前岛叶皮层之间的CI增加，连接左伏隔核和后岛叶皮层的通路的FA增加。我们的结果支持先前的证据，即精神分裂症不同临床亚型的不同神经生物学改变。DS,与NDS和HC相比，可能会在涉及更新刺激值以指导目标导向行为的大脑区域中出现改变的修剪过程（与超连接性一致）。
