Discipline of Psychiatry, Sydney Medical School, University of Sydney, NSW 2065, Australia.
Schizophr Res. 2012 Sep;140(1-3):51-8. doi: 10.1016/j.schres.2012.06.023. Epub 2012 Jul 12.
Schizophrenia can be conceptualized as a disorder of functional connectivity within the fronto-temporal (FT) and/or default-mode (DM) networks. Recent evidence suggests that dysfunctional integration between these large neural networks may also contribute to the illness, and that the ability to mentalize or have a Theory of Mind (ToM) is discernibly impaired in patients with schizophrenia. Hence in this study, we examined whether impaired functional network connectivity (FNC) contributes to a compromise in the ability to mentalize in patients with schizophrenia. Functional magnetic resonance imaging data were acquired from 20 male schizophrenia patients and 19 matched healthy controls while performing a well-known ToM task. The study revealed that relative to non-ToM the engagement of ToM produced reduced neural activity in the lateral FT and insula networks in patients, as compared to healthy subjects. The findings also indicated that in comparison to healthy subjects the DM and medial FT networks are less suppressed in patients irrespective of the task (ToM/non-ToM). Further, FNC analyses showed that the degree of functional connectivity between task-positive (lateral FT and insula) and task-negative (medial FT, posterior DM) networks was significantly reduced in patients as compared to controls. Of note, a significant correlation between the functional connectivity strength of the lateral FT network with the medial FT and the degree to which this is modulated by the ToM task, suggests that mentalizing deficits in male schizophrenia patients may stem from impaired communication between neural networks that comprehend the mental states of self (medial FT) and others (lateral FT).
精神分裂症可以被概念化为额颞(FT)和/或默认模式(DM)网络内功能连接的障碍。最近的证据表明,这些大型神经网络之间的功能整合障碍也可能导致疾病,并且精神分裂症患者的心理化或心理理论(ToM)能力明显受损。因此,在这项研究中,我们检查了功能网络连接(FNC)的损伤是否会导致精神分裂症患者心理化能力的下降。我们从 20 名男性精神分裂症患者和 19 名匹配的健康对照者中获取了功能磁共振成像数据,同时让他们执行一个著名的 ToM 任务。研究结果表明,与非 ToM 任务相比,精神分裂症患者在执行 ToM 任务时,外侧 FT 和岛叶网络的神经活动减少,而健康受试者则没有这种情况。研究结果还表明,与健康受试者相比,无论任务(ToM/非 ToM)如何,DM 和内侧 FT 网络在患者中的抑制作用都较小。此外,FNC 分析表明,与对照组相比,患者的任务正激活(外侧 FT 和岛叶)和任务负激活(内侧 FT、后 DM)网络之间的功能连接程度显著降低。值得注意的是,外侧 FT 网络的功能连接强度与内侧 FT 网络之间存在显著相关性,并且这种相关性受 ToM 任务的调节程度,表明男性精神分裂症患者的心理化缺陷可能源于理解自我(内侧 FT)和他人(外侧 FT)心理状态的神经网络之间的通讯受损。