Dr. Sundermann et al. analyzed the spatial information about alterations of spontanueous brain activity in major depressive disorder and aimed to improve the diagnostic accuracy. The aim of the study is clear. Authors applied meta-analysis including 32 studies and calculated the data. However, the major results didn't be described clearly in the Abstract. The title is informative and relevant. The references are cited correctely and appropriately.

In the Introduction, authors introduced the different analysis methods for MRI study of patients with MDD. However, the research question is not clearly outlined? Some issues are concerned as following: 1.However, authors didn’t describe clearly the difference between resting MRI and task-MRI study in the
background. 2.Why the research focused on the resting MRI studies? What’s mean of the association between the founding of rs MRI and MDD? 3. In background, authors should introduce the classic pathological mechanism of MDD which was based on resting MRI studies.

MDD is a Heterogenous mental disease. Different sub-type or clinical features might have potential pathological mechanism of neural activities.

4.In the study, how to deal with the heterogeneity of the subjects?

1. Authors applied coordinate-based meta-analysis and separated the studies according to the directionality of findings. I think this analysis just was based on the transcendental knowledge. Authors didn’t account for the sample bias, and should conduct meta-analysis in certain homogenous subjects, such as first-episodic MDD without medication.

The results were presented in different activities of FC in MDD. The significant results were described clearly. However, the results section still has some problem I was concerned. 6..Based on primary results, the rsMRI studies was grouped in different group. The meta-analysis of studies with decrease FC results was not seen. 7.As we known, resting functional networks including DMN，cognitive network, emotional network and frontal-temporal network and so on. Authors would better conduct above network analysis. In results, there is no association analysis of significant changes in brain activities with clinical measurements. Reader can’t get to know the value for clinical practice.

In Discussion, there are some issues as following which I am concerned. 8.The major results should be stated firstly in discussion section. Author needn’t describe the detailed results again. 9.How to give interpretation for the major founding is crucial for the study aims. Authors should add such statements. 10.The limitation could be described more briefly. 11.The conclusion in the text failed to deal with the primary hypothesis in the introduction.