Table 6.

rs-fMRI studies with LLD, HC, and additional comparison groups.

References	N (LLD/HC/MCI/ LLD+MCI)	Study type	Depression status	Analysis method	Frontal-executive findings	Corticolimbic findings	Other findings
Xie et al. (2013)	72 (18/25/17/12	Cross-sectional	Current	Seed (Hippo)	LLD vs. non-depressed• Left hippo: Decreased anti-correlation R-dlPFC1• Right hippo: Increased FC in bilat-Thal2, and R-Lent3, decreased anti-correlated FC in l-dlPFC and d-striatum4 MCI vs. non-CI• Left hippo: Decreased + and – FC in bilat-dlPFC, IPC5, L- pMTG6; and R-dACC7 and SPC8.• Right hippo: Decreased + and - FC in bilat-aTP9 and IPC5; L-vlPFC10, pMTG; R-ITC11. Interactive effect of LLD*MCI• Right hippo: Found in bilat-MOG12, L-dACC, R-dlPFC/dACC cluster	LLD vs. non-depressed• Left hippo: Increased FC bilat-PCC13, and R-dmPFC14• Right hippo: Increased FC in L-Hippo MCI vs. non-CI• Left hippo: Decreased + and – FC in bilat-dmPFC• Right hippo: Decreased + and – FC in bilat-aTP9, PHG15 Interactive effect LLD*MCI• Right hippo: Found in vmPFC16	LLD vs. non-depressed• Right hippo: Decreased anti- correlated FC in bilat-MOG13 MCI vs. non-CI:• Left hippo: Decreased + and – FC in bilat-RSC17; L-postCG18
Li et al. (2015b)	63 (25/26/-/15)	Cross-sectional	Current	Seed (Amygdala)	LLD vs. HC Decreased FC in R-SPL19, MFG20, IFG21, ITG22 Increased in cerebellar vermis LLD+aMCI vs. HC Decreased FC in bilat-SPL, R-IFG, MFG; and MTG23 Increased FC in IPL24 LLD+aMCI vs. LLD Decreased FC in L-MTG20	LLD vs. HC Increased FC in R-PCC13 and TP25 LLD+aMCI vs. HC Decreased FC in left TP, PHG15, hippo26, cuneus LLD+aMCI vs. LLD Greater decrease of FC in the bilateral TP, cuneus (posterior DMN35)	LLD+MCI vs. LLD Decreased FC in OG27 LLD vs. HC decreased FC in PreCG28 LLD+aMCI vs. HC Decreased FC in PreCG, bilat-IOG29 and MOG30 LLD+aMCI vs. LLD Decreased FC in bilat-FFG31, IOG, MOG
Chen et al. (2016)	256 (55/114/87)	Cross-sectional	Remitted	Correlation between each pair of 36 seeds that represent five major RSNs32	LLD vs. HC: Reduced FC degree in bilat-ITG22 MCI vs. HC: Trend toward increased FC degree at all nodes (except for r-ITG22)	LLD vs. HC: Reduced FC strength in ECN33-DMN35 *After controlling for age, sex, education and APOE genotype: reduced correlation in ECN-DMN pair in LLD > MCI vs. HC	LLD vs. HC: Reduced FC degree in SMA36 LLD vs. HC: Reduced FC strength in SMN37 aMCI vs. HC: A trend toward increased FC strength within SAL and SMN LLD vs. aMCI: Reduced FC strength within SAL38 and SMN
Li et al. (2015a)	79 (23/25/18/13)	Cross-sectional	Current	Graph theory threshold range (0.03–0.5)	LLD, aMCI, LLD+aMCI vs. HC Combined ECN/VAN split into two distinct modules: ECN33 and VAN34	LLD and aMCI vs. HC DMN module was split into two smaller modules	LLD vs. HC Disrupted FC segregation (decreased local efficiency) LLD+aMCI > LLD > MCI Greatest mean nodal efficiency LLD+aMCI vs. aMCI Decreased local efficiency LLD+aMCI vs. all other groups greatest disruptions in integration (diminished global efficiency) LLD+aMCI Had most variable modular community followed by LLD

¹dorsolateral prefrontal cortex (dlPFC);

²thalamus (Thal);

³lentiform nucleus (Lent);

⁴dorsal striatum (caudate and putamen) d-striatum;

⁵inferior parietal cortex (IPC);

⁶left posterior middle temporal gyrus (pMTG);

⁷dorsal anterior cingulate cortex (dACC);

⁸superior parietal cortex (SPC);

⁹anterior temporal pole (aTP);

¹⁰ventrolateral prefrontal cortex (vlPFC);

¹¹inferior temporal cortex (ITC);

¹²middle occipital gyrus (MOG);

¹³posterior cingulate cortex (PCC);

¹⁴dorsomedial prefrontal cortex (dmPFC);

¹⁵parahippocampal gyrus (PHG);

¹⁶ventromedial prefrontal cortex (vmPFC);

¹⁷retro-splenial cortex (RSC);

¹⁸post central gyrus (postCG);

¹⁹superior parietal lobe (SPL);

²⁰middle frontal gyrus (MFG);

²¹inferior frontal gyrus (IFG);

²²inferior temporal gyrus (ITG);

²³middle temporal gyrus (MTG);

²⁴inferior parietal lobule (IPL);

²⁵temporal pole (TP);

²⁶hippocampus (hippo);

²⁷occipital gyri (OG);

²⁸pre-central gyrus (PreCG);

²⁹inferior occipital gyrus (IOG);

³⁰middle occipital gyrus (MOG);

³¹fusiform gyrus (FFG);

³²resting state networks (RSN);

³³executive control network (ECN);

³⁴ventral attention network (VAN);

³⁵default mode network (DMN);

³⁶supplemental motor area (SMA);

³⁷sensory-motor network (SMN);

³⁸salience network (SAL).