Their basic idea was to start with all voxels and iteratively eliminate the “least informative” voxel (i.e., the smallest weight) at each cycle. This process was repeated until there was no need to delete voxels. Obviously, this method is more time consuming compared with our approach. Our results demonstrated that the voxel-wise time series extracted from reversal coarse-grained analysis have a few advantages over ROI-wise time series extracted from coarse-grained analysis. First,

the voxel-wise time series Inhibitors,research,lifescience,medical had larger ALFFs for all three areas related to the hate circuit (Fig. ​(Fig.4A).4A). In previous studies, ALFF was thought to reflect selleck chem Tipifarnib spontaneous neural activity (Fox and Raichle 2007), which was correlated with activity in gamma-band power (Shmuel and Leopold 2008); this in turn reflects increased regionally synchronized neuronal connectivity and is associated with a capacity for higher cognitive functions (Lewis et al. 2008). The enhancement of ALFF reflects Inhibitors,research,lifescience,medical that the regional neuronal populations function in a more Inhibitors,research,lifescience,medical synchronous manner within the source subregions than in the entire region. Second, a

reversal coarse-grained analysis resulted in the attenuation of functional connectivity, both for the SFGdor–INS and INS–PUT connectivities (Fig. ​(Fig.3A),3A), probably because the localized subregions Inhibitors,research,lifescience,medical led to a reduction of the integration of synchronous

activity across brain regions. The greater difference of these two links between the two groups indicated that a more significant difference could be detected. However, it is unclear whether this selleck chemicals Vismodegib reduced connectivity is beneficial. The pattern of increased ALFF, together with reduced network level connectivity, suggests that increased spontaneous Inhibitors,research,lifescience,medical regional neural activity is associated with a parallel reduction, rather than with an enhancement in the coherence of activity across the three source regions (SFGdor, INS, and PUT). Third, reversal coarse-grained analysis had a greater effect (in terms of both odds ratio and risk difference) on functional connectivity (SFGdor–INS and INS–PUT); this means that the identified subregions exhibited significant differences between the two groups. Our discrimination results showed that feature selection, based on reversal coarse-grained analysis, Batimastat yields a better classification performance. In fact, many discrimination analyses performed at the voxel level yielded high discrimination accuracy. For example, a classification method was proposed to distinguish subjects of two groups using multiple independent components and their combinations, with the independent component extracted on the basis of the time series of each voxel (Calhoun et al. 2008; Demirci et al. 2008).