Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London, London SE5 8AB, United Kingdom; Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand.
Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London, London SE5 8AB, United Kingdom.
Neurosci Biobehav Rev. 2023 Jan;144:104940. doi: 10.1016/j.neubiorev.2022.104940. Epub 2022 Nov 2.
Functional magnetic resonance spectroscopy (fMRS) can be used to investigate neurometabolic responses to external stimuli in-vivo, but findings are inconsistent. We performed a systematic review and meta-analysis on fMRS studies of the primary neurotransmitters Glutamate (Glu), Glx (Glutamate + Glutamine), and GABA. Data were extracted, grouped by metabolite, stimulus domain, and brain region, and analysed by determining standardized effect sizes. The quality of individual studies was rated. When results were analysed by metabolite type small to moderate effect sizes of 0.29-0.47 (p < 0.05) were observed for changes in Glu and Glx regardless of stimulus domain and brain region, but no significant effects were observed for GABA. Further analysis suggests that Glu, Glx and GABA responses differ by stimulus domain or task and vary depending on the time course of stimulation and data acquisition. Here, we establish effect sizes and directionality of GABA, Glu and Glx response in fMRS. This work highlights the importance of standardised reporting and minimal best practice for fMRS research.
功能磁共振波谱（fMRS）可用于研究活体对外界刺激的神经代谢反应，但研究结果不一致。我们对主要神经递质谷氨酸（Glu）、Glx（谷氨酸+谷氨酰胺）和 GABA 的 fMRS 研究进行了系统评价和荟萃分析。提取数据，按代谢物、刺激域和脑区分组，并通过确定标准化效应大小进行分析。对单个研究的质量进行了评分。当按代谢物类型分析结果时，无论刺激域和脑区如何，Glu 和 Glx 的变化均观察到 0.29-0.47 的小到中等效应大小（p<0.05），但 GABA 没有观察到显著影响。进一步的分析表明，Glu、Glx 和 GABA 的反应因刺激域或任务而异，并且取决于刺激的时程和数据采集。在这里，我们确定了 fMRS 中 GABA、Glu 和 Glx 反应的效应大小和方向。这项工作强调了标准化报告和 fMRS 研究的最小最佳实践的重要性。
