Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London, UK.
Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.
NMR Biomed. 2024 Jul;37(7):e5092. doi: 10.1002/nbm.5092. Epub 2023 Dec 28.
Several studies have suggested that atypical social processing in neurodevelopmental conditions (e.g. autism) is associated with differences in excitation and inhibition, through changes in the levels of glutamate and gamma-aminobutyric acid (GABA). While associations between baseline metabolite levels and behaviours can be insightful, assessing the neurometabolic response of GABA and glutamate during social processing may explain altered neurochemical function in more depth. Thus far, there have been no attempts to determine whether changes in metabolite levels are detectable using functional MRS (fMRS) during social processing in a control population. We performed Mescher-Garwood point resolved spectroscopy edited fMRS to measure the dynamic response of GABA and glutamate in the superior temporal sulcus (STS) and visual cortex (V1) while viewing social stimuli, using a design that allows for analysis in both block and event-related approaches. Sliding window analyses were used to investigate GABA and glutamate dynamics at higher temporal resolution. The changes of GABA and glutamate levels with social stimulus were largely non-significant. A small decrease in GABA levels was observed during social stimulus presentation in V1, but no change was observed in STS. Conversely, non-social stimulus elicited changes in both GABA and glutamate levels in both regions. Our findings suggest that the current experimental design primarily captures effects of visual stimulation, not social processing. Here, we discuss the feasibility of using fMRS analysis approaches to assess changes in metabolite response.
已有多项研究表明，神经发育障碍（如自闭症）中的非典型社会处理与谷氨酸和γ-氨基丁酸（GABA）水平的变化有关，这些变化与兴奋和抑制的差异有关。虽然代谢物基线水平与行为之间的相关性具有启发性，但评估 GABA 和谷氨酸在社会处理过程中的神经代谢反应可能更深入地解释神经化学功能的改变。到目前为止，还没有人试图确定在对照组人群的社会处理过程中，是否可以使用功能磁共振波谱（fMRS）检测代谢物水平的变化。我们使用 Mesche-Garwood 点分辨波谱编辑 fMRS 来测量上颞叶回（STS）和视觉皮层（V1）中 GABA 和谷氨酸的动态反应，同时观看社会刺激，该设计允许在块和事件相关方法中进行分析。滑动窗口分析用于以更高的时间分辨率研究 GABA 和谷氨酸的动力学。GABA 和谷氨酸水平随社会刺激的变化大多不显著。在 V1 中观察到社会刺激呈现时 GABA 水平略有下降，但在 STS 中没有观察到变化。相反，非社会刺激在两个区域都引起了 GABA 和谷氨酸水平的变化。我们的研究结果表明，当前的实验设计主要捕获视觉刺激的影响，而不是社会处理。在这里，我们讨论了使用 fMRS 分析方法评估代谢物反应变化的可行性。
