Table 3.

Representative MRI studies investigating a putative association between inflammation and structural/functional changes in the brain in MDD

Study	Characteristics of MDD samples	Number of participants per group		Brain regions	Method
		MDD	HC
Felger et al. (2016) [98]	Medically stable MDD	48	0	Ventral striatum and vmPFC	Functional connectivity
Meier et al. (2016) [99]		73	91	mPFC	Cortical volume, thickness, and surface area
Frodl et al. (2012) [100]	MDD	40	43	Hippocampus	Manual tracing of the bilateral hippocampal and amygdala structure

Abbreviations: HC healthy controls, MDD major depressive disorder, mPFC medial prefrontal gyrus, vmPFC ventromedial prefrontal gyrus