Objective:To clarify altered whole brain functional connectivity of the anterior cingulate cortex(ACC)in functional dyspepsia(FD)patients,and then to explore cerebral influence of acupuncture with deqi treating for FD.rnMethods:Thirty-two FD patients and 35 healthy subjects(HS)were firstly scanned by the resting-state blood oxygenation level-dependent functional magnetic resonance imaging(BOLD-fMRI)to compare dif-ferences of ACC-based functional connectivity(FC).Then 32 FD patients were randomized to receive 20 sessions'acupuncture treatment with(n=16)and without deqi(n=16),as well as underwent functional magnetic resonance imaging(fMRI)scans after treatment.After group re-division according to deqi re-sponse,changes of ACC subregions-based resting-state FC(rsFC)were compared between the actual with and without deqi group.Two seeds with bilateral of each were selected as regions of interest(ROls)of the ACC,including two from the dorsal ACC:S2(BA24)(x=±5,y=2,z=46,r=3.5 mm)and two from the pre-genual ACC:17(BA24)(x=±5,y=38,z=6,r=3.5 mm).The clinical changes of the Nepean Dyspepsia Index(NDI)that measuring symptoms and quality of life(QOL)were also used to further assess the correlation with ACC subregions rsFC in FD patients.rnResults:Compared to HS,FD patients showed significantly increased ACC subregions rsFC with left fusiform gyrus,temporal cortex,hippocampus(HIPP)/amygdala,temporal pole,and right INS,superior oc-cipital gyrus,and bilateral precuneus,superior parietal lobule(SPL),and decreased rsFC with left postcen-tral/precentral gyrus(PoG/PrG),supplementary motor area(SMA)and right cerebellum.32 FD patients which were then re-divided into the actual deqi group(n=16)and actual without deqi group(n=16).The decrease of the NDI symptom score(pre-pos)in the actual deqi group was significantly greater than that in the actual without deqi group(P＜0.05).Among the two groups,the actual deqi group showed increased ACC subregions rsFC with right SMA and bilateral PrG/PoG,and decreased rsFC with right pre-cuneus,middle occipital gyrus,bilateral posterior cingulate cortex(PCC),HIPP/paraHIPP,angular gyrus and SPL after treatment.In addition,the changed NDI QOL scores(pre-post)of the actual deqi group was significantly positively correlated with their Fisher's transformed Z value of the altered ACC subregion(left 17)rsFC with right SPL(r=-0.597,P=0.04＜0.05,FDR corrected P＞0.05).rnConclusion:The results tested the hypothesis that the advantage of deqi on efficacy is related to affecting the ACC subregions rsFC.It suggested that deqi might participate in the adaptive modulation of disrupted relationship between the ACC subregions and the default mode network(DMN).