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Journal of Clinical and
Basic Psychosomatics Brain MRI alterations in MDD

resting-state brain function changes only after the acute Funding
phase of antidepressant treatment; thus, the impact of
long-term treatment with antidepressants is unclear. The This study was supported by grants from the Science
inherent multi-dimensional nature of establishing MRI- and Technology Program of Guangzhou (Grant
based biomarkers for predicting treatment outcomes is No. 202002030262), the Basic and Applied Basic Research
Fund of Guangdong (Grant No. 2021A1515220103), and
challenging. The heterogeneity of MDD is one of the most the National Natural Science Foundation of China (Grant
important factors, and the heterogeneity of antidepressants No. 82171508).
regarding type and dose may affect the accuracy and
reproducibility of the studies. Thus, neuroimaging studies Conflict of interest
in different subtypes of MDD can help understand the
underlying neuropathological mechanisms associated The authors have no conflicts to disclose.
with disease stages and heterogeneity, from which Author contributions
neuroimaging markers that could aid in early diagnosis
can be identified. Conceptualization: All authors
In addition, growing evidence suggests that MDD Writing – original draft: Lulu Zhang
involves abnormalities in several brain regions and Writing – review & editing: All authors
networks closely related to emotion and cognition. Ethics approval and consent to participate
However, some of these studies are limited to a single
method of data analysis. Further longitudinal studies using Not applicable.
multimodal fMRI are needed to clarify its pathogenesis
and treatment mechanisms and rapidly progress the field Consent for publication
of neuroimaging. The hardware standard has shifted from Not applicable.
1.5T MRI to 3T MRI and is currently moving to 7T. Recent
studies have analyzed more appropriate sample sizes, but Availability of data
this puts a larger onus on recruitment, typically involves Not applicable.
multiple sites, and raises further complications for data
[63]
harmonization . The statistically significant findings References
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Acknowledgments
6. Suda K, Matsuda K, 2022, How microbes affect depression:
None. Underlying mechanisms via the gut-brain axis and the

Volume 1 Issue 1 (2023) 6 https://doi.org/10.36922/jcbp.0896