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Background:Blood oxygen level dependent(BOLD)signal fluctuations explain neural synchronization and cognitive behaviors and are used in brain disorders.The low frequency BOLD fluctuations(usually lower than 0.25 Hz)have been shown frequency specific characteristics in synchronization(Wu et al.2008).In the last decade,numerous studies have demonstrated the BOLD fluctuations using amplitude of low frequency fluctuations(ALFF),regional homogeneity(ReHo)and functional connectivity(FC)methods by analyzing the structural and functional imaging(zuo et al.2010).Then we use a new data-driven method--functional connectivity density(FCD)mapping—to research the functional separation and functional integration.(DardoTomasi.et al.2010)specially,we use a sliding windows analysis to detect the frequency specificity of BOLD fluctuations(Hutchison et al.2013).Methods:Herewe used the rest-state fMRI data(64 subjects :35male and 29 female,17-30 years,mean age:22.06±2.44).Data were preprocessed using DPARSF toolbox including temporal and spatial correction,normalization,regressed out the nuisances and respiratory and cardiac signals.using the sliding windows analysis and FCD methods.And the local FCD(lFCD)and long-range FCD data underwent spatial smoothing [8-mm full width at half maximum(FWHM)Guassian kernel].Results: Our results showedlFCD and long-range FCD effects in full frequency,the main regions are precuneus,posterior cingulate cortex,cerebellum,frontal gyrus,temporal gyrus,parahippocampa gyrus,lingual gyrus and limbic regions.The results was statistically significant in all gray matter regions.The frequency effects showed the precuneus,superior temporal gyrus,hippocampal gyrus,superior frontal gyrus and cerebellum.To get a clear inspection,we surveyed the maximum and minimum of lFCDand long-range FCD for each voxel and averaged across subjects.Discussion: In the present study,we calculated the different frequency ban sales of lFCD and long-range FCD mapping,to research the BOLD fluctuations characteristics.The frequency characteristics BOLD fluctuations are of importance for understanding the meaning of BOLD signal and brain activities.(Chang et al.2009)The results suggest that there may be multiple mechanisms of the frequency characteristics of BOLD fluctuations(Song et al.2014).