It has been proposed that the Glutamate (Glu) system is implicated in autism spectrum disorders (ASD) via an imbalance between excitatory and inhibitory brain circuits, which impacts on brain function. Here, we investigated the excitatory-inhibitory imbalance theory by measuring Glu-concentrations and the relationship with resting-state function. Nineteen adult males with ASD and 19 age and sex-matched healthy controls (HC) (23 - 58 years) underwent Proton Magnetic Resonance Spectroscopy of the dorsal anterior cingulate cortex (dACC) and resting-state functional Magnetic Resonance Imaging (fMRI). Glu and Glx concentrations were compared between groups. Seed-based functional connectivity was analyzed with a priori seeds of the right and left dACC. Finally, metabolite concentrations were related to functional connectivity coefficients and compared between both groups. Individuals with ASD showed significantly negative associations between increased Glx concentrations and reduced functional connectivity between the dACC and insular, limbic and parietal regions. In contrast, HC displayed a positive relationship between the same metabolite and connectivity measures. We provided new evidence to support the excitatory-inhibitory imbalance theory, where excitatory Glx concentrations were related to functional dysconnectivity in ASD. Future research is needed to investigate large-scale functional networks in association with both excitatory and inhibitory metabolites in subpopulations of ASD.

已经提出，谷氨酸（Glu）系统通过兴奋性和抑制性脑回路之间的不平衡而与自闭症谱系障碍（ASD）有关，这会影响脑功能。在这里，我们通过测量Glu浓度及其与静止状态功能的关系，研究了兴奋抑制性失衡理论。19名ASD和19个年龄和性别相匹配的健康对照（HC）（23-58岁）的成年男性接受了前扣带回皮层（dACC）的质子磁共振波谱分析和静止状态功能磁共振成像（fMRI）。比较各组之间的Glu和Glx浓度。基于种子的功能连接性使用左右dACC的先验种子进行了分析。最后，代谢物浓度与功能连接系数有关，并在两组之间进行了比较。ASD患者在Glx浓度升高和dACC与岛，缘和顶叶区域之间的功能连通性降低之间显示出显着的负相关性。相反，HC在相同代谢物和连通性指标之间显示出正相关关系。我们提供了新的证据来支持兴奋性-抑制性不平衡理论，其中兴奋性Glx浓度与ASD的功能不连通有关。需要进一步的研究来研究与ASD亚群中的兴奋性和抑制性代谢物相关的大规模功能网络。ASD患者在Glx浓度升高和dACC与岛，缘和顶叶区域之间的功能连通性降低之间显示出显着的负相关性。相反，HC在相同代谢物和连通性指标之间显示出正相关关系。我们提供了新的证据来支持兴奋性-抑制性不平衡理论，其中兴奋性Glx浓度与ASD的功能不连通有关。需要进一步的研究来研究与ASD亚群中的兴奋性和抑制性代谢物相关的大规模功能网络。ASD患者在Glx浓度升高和dACC与岛，缘和顶叶区域之间的功能连通性降低之间显示出显着的负相关性。相反，HC在相同代谢物和连通性指标之间显示出正相关关系。我们提供了新的证据来支持兴奋性-抑制性不平衡理论，其中兴奋性Glx浓度与ASD的功能不连通有关。需要进一步的研究来研究与ASD亚群中的兴奋性和抑制性代谢物相关的大规模功能网络。我们提供了新的证据来支持兴奋性-抑制性不平衡理论，其中兴奋性Glx浓度与ASD的功能不连通有关。需要进一步的研究来研究与ASD亚群中的兴奋性和抑制性代谢物相关的大规模功能网络。我们提供了新的证据来支持兴奋性-抑制性不平衡理论，其中兴奋性Glx浓度与ASD的功能不连通有关。需要进一步的研究来研究与ASD亚群中的兴奋性和抑制性代谢物相关的大规模功能网络。