Co-activation patterns distinguish cortical modules, their connectivity and functional differentiation

“…physiology of correlations in the absence of a structured task remains somewhat elusive, it seems plausible that “resting” state, as a mixture of various cognitive processes, may likewise sample the repertoire of operations brain networks can perform (Buckner and Vincent, 2007; Smith et al., 2009).”

“Other approaches such as psychophysiological interactions or Granger causalitymapping are used to identify regions, showing a context-dependent change in their coupling with a particular seed region (Friston et al., 1997; Goebel et al., 2003) under the assumptions of the employed model.”

“…likely conveying meaningful functional relationships between brain regions are illustrated by the fact that they were reported to widely correspond with both task-state networks (Biswal et al., 1995; Smith et al., 2009) and structural connectivity (Greicius et al., 2009; Hagmann et al., 2008).”

“In addition, a necessary step toward understanding cortical organization is to relate connectivity-defined modules and functional differentiations to microstructural maps of the human cerebral cortex (Amunts et al., 2007; Eickhoff et al., 2005; Eickhoff et al., 2008b; Zilles et al., 2002).”

“Other approaches such as psychophysiological interactions or Granger causalitymapping are used to identify regions, showing a context-dependent change in their coupling with a particular seed region (Friston et al., 1997; Goebel et al., 2003) under the assumptions of the employed model.”

“On these, tractography algorithms may be employed to derive information about the most likely fiber tract direction from particular seed or the course and strength of pathways connecting two different regions of the cortex (Behrens et al., 2003; Ramnani et al., 2004).”

“…likely conveying meaningful functional relationships between brain regions are illustrated by the fact that they were reported to widely correspond with both task-state networks (Biswal et al., 1995; Smith et al., 2009) and structural connectivity (Greicius et al., 2009; Hagmann et al., 2008).”

“…described co-activation parcellation of the seed region, ALE scores for the MACM analysis of this cluster were compared to a null-distribution that reflects a random spatial association between experiments, but regards the within-experiment distribution of foci as fixed (Eickhoff et al., 2009).”

“It thus summarizes any analysis that assesses correlations among brain signals without the explicit modeling of the underlying networks (as in effective connectivity), ranging from spike train correlations (Nuding et al., 2009) to EEG coherence (Gross et al., 2001) and various fMRI basedmethods.”

“Together with previous computational modeling (Honey et al., 2007), this supports the notion of a good congruency between anatomical and functional connectivities.”

“Based on these observations and functional activation studies, the SMA has been implicated in executive aspects of motor control, e.g. movement initiation (Chouinard and Paus, 2006; Cunnington et al., 2002; Eickhoff et al., 2008a; Picard and Strick, 1996).”

“Regions that co-activated with both clusters delineated in the medial premotor cortex by the co-activation based parcellation were identified using a minimum-statistic conjunction by computing the intersection of the thresholded ALE-maps (Caspers et al., 2010; Kurth et al., 2010).”

“Regions that co-activated with both clusters delineated in the medial premotor cortex by the co-activation based parcellation were identified using a minimum-statistic conjunction by computing the intersection of the thresholded ALE-maps (Caspers et al., 2010; Kurth et al., 2010).”

“Fax: + E-mail address: S.Eickhoff@fz-juelich.de (S.B. Eickho 1053-8119/$ – see front matter © 2011 Elsevier Inc. Al doi:10.1016/j.neuroimage.2011.05.021 a b s t r a c t a r t i c l e i n f o”

“In the widely used Dynamic Causal Modeling (DCM) and Structural Equation Modeling (SEM) approaches, this is assessed by taking an explicit network perspective and modeling the interactions between regions as a function of the experimental context (Buchel and Friston, 1997; Stephan et al., 2007).”

“Supporting this view, connectivity tracing in non-human primates revealed that the preSMA receives afferences from the inferior parietal lobule (Luppino et al., 1993) and the prefrontal cortex.”

“Approaches investigating cortical sub-specialization capitalized on this type of inter-regional connectivity, such as for the successful parcellation of the premotor cortex (Kim et al., 2010), insular cortex (Cauda et al., 2011), and thalamus (Zhang et al., 2008).”

“Following earlier reports that cortical modules may be defined by differences in anatomical connectivity (Johansen-Berg et al., 2004; Klein et al., 2007; Tomassini et al., 2007) or resting state correlations (Kim et al.”

“The latter correlate regional BOLD signal changes in order to quantify the degree of functional connectivity between them or identify regions that correlate with a particular seed (Hampson et al., 2002; Ramnani et al., 2004; Xiong et al., 1999).”

“Other approaches such as psychophysiological interactions or Granger causalitymapping are used to identify regions, showing a context-dependent change in their coupling with a particular seed region (Friston et al., 1997; Goebel et al., 2003) under the assumptions of the employed model.”

“Analysis of the behavioral domain and paradigm class meta-data (Laird et al., 2009a) moreover allowed the delineation of functional characteristics for the ensuing cortical modules.”

“Evidence from primate research indicated that microstructure and connectivity of the cortex are the main determinants of its functional segregation (Luppino et al., 1991; Matelli et al., 1991).”

“Based on these observations and functional activation studies, the SMA has been implicated in executive aspects of motor control, e.g. movement initiation (Chouinard and Paus, 2006; Cunnington et al., 2002; Eickhoff et al., 2008a; Picard and Strick, 1996).”

“Evidence from primate research indicated that microstructure and connectivity of the cortex are the main determinants of its functional segregation (Luppino et al., 1991; Matelli et al., 1991).”

“By comparing the anatomical connectivity profiles of the individual seed voxels with each other, these can then be grouped into distinct clusters of homogeneous connectivity (Anwander et al., 2007; Johansen-Berg et al., 2004; Klein et al., 2007).”

“While the underlying physiology of correlations in the absence of a structured task remains somewhat elusive, it seems plausible that “resting” state, as a mixture of various cognitive processes, may likewise sample the repertoire of operations brain networks can perform (Buckner and Vincent, 2007; Smith et al., 2009).”

“Among those, effective connectivity analyses, such as dynamic causal modeling (Friston et al., 2003) or structural equation modeling (Buchel and Friston, 1997), allow the investigation of taskdependent influences among cortical areas (Grefkes et al., 2008).”

“Approaches investigating cortical sub-specialization capitalized on this type of inter-regional connectivity, such as for the successful parcellation of the premotor cortex (Kim et al., 2010), insular cortex (Cauda et al., 2011), and thalamus (Zhang et al., 2008).”

“DTI, resting state analyses, and MACM each focus on a different aspects of connectivity, and we therefore predict that in spite of their good convergence, each capture different features of cortical organization (Eickhoff et al., 2010; Honey et al., 2007; Ramnani et al., 2004).”

“Based on these observations and functional activation studies, the SMA has been implicated in executive aspects of motor control, e.g. movement initiation (Chouinard and Paus, 2006; Cunnington et al., 2002; Eickhoff et al., 2008a; Picard and Strick, 1996).”

“…earlier reports that cortical modules may be defined by differences in anatomical connectivity (Johansen-Berg et al., 2004; Klein et al., 2007; Tomassini et al., 2007) or resting state correlations (Kim et al., 2010) we demonstrated that SMA and pre-SMA may be distinguished by amodel-free…”

“While many hypotheses derived in particular from primate work (Bremmer et al., 2001) and lesion mapping studies (Riecker et al., 2005) could be explicitly tested using this approach, neuroimaging is intrinsically less well suited to delineate the organization of a particular brain region.”

“and Luppino, 2001; Vogt et al., 2007).”

“, 2007) or resting state correlations (Kim et al., 2010) we demonstrated that SMA and pre-SMA may be distinguished by amodel-free analysis of co-activation patterns across activation studies.”

“In addition, a necessary step toward understanding cortical organization is to relate connectivity-defined modules and functional differentiations to microstructural maps of the human cerebral cortex (Amunts et al., 2007; Eickhoff et al., 2005; Eickhoff et al., 2008b; Zilles et al., 2002).”

“On these, tractography algorithms may be employed to derive information about the most likely fiber tract direction from particular seed or the course and strength of pathways connecting two different regions of the cortex (Behrens et al., 2003; Ramnani et al., 2004).”

“In addition, a necessary step toward understanding cortical organization is to relate connectivity-defined modules and functional differentiations to microstructural maps of the human cerebral cortex (Amunts et al., 2007; Eickhoff et al., 2005; Eickhoff et al., 2008b; Zilles et al., 2002).”

“In the widely used Dynamic Causal Modeling (DCM) and Structural Equation Modeling (SEM) approaches, this is assessed by taking an explicit network perspective and modeling the interactions between regions as a function of the experimental context (Buchel and Friston, 1997; Stephan et al., 2007).”

“Following earlier reports that cortical modules may be defined by differences in anatomical connectivity (Johansen-Berg et al., 2004; Klein et al., 2007; Tomassini et al., 2007) or resting state correlations (Kim et al., 2010) we demonstrated that SMA and pre-SMA may be distinguished by amodel-free…”

“, a functional differentiation between two regions (Reddy and Kanwisher, 2006) or a dichotomy between the neural correlates of two processes (Charron and Koechlin, 2010).”

“, a functional differentiation between two regions (Reddy and Kanwisher, 2006) or a dichotomy between the neural correlates of two processes (Charron and Koechlin, 2010).”

“…that diffusion-based tractography does not provide information about anatomical connectivity sensu stricto, i.e. axonal connectivity as revealed by tracer studies in macaques (Pons and Kaas, 1985), but can merely assess the presence and strength of macroanatomical fiber bundles between regions.”

“We then assessed whether the two original regions could be recovered in a model-free analysis from this merged, i.e., single, VOI based on similarities between co-activation patterns of the individual seed voxels across neuroimaging experiments.”

“Based on these observations and functional activation studies, the SMA has been implicated in executive aspects of motor control, e.g. movement initiation (Chouinard and Paus, 2006; Cunnington et al., 2002; Eickhoff et al., 2008a; Picard and Strick, 1996).”

“Sets of voxels that feature similar brain-wide coactivation profiles were identified by hierarchical cluster analysis (Eickhoff et al., 2007; Timm, 2002).”

“Based on these observations and functional activation studies, the SMA has been implicated in executive aspects of motor control, e.g. movement initiation (Chouinard and Paus, 2006; Cunnington et al., 2002; Eickhoff et al., 2008a; Picard and Strick, 1996).”

“It thus summarizes any analysis that assesses correlations among brain signals without the explicit modeling of the underlying networks (as in effective connectivity), ranging from spike train correlations (Nuding et al., 2009) to EEG coherence (Gross et al., 2001) and various fMRI basedmethods.”

“…brain region or provide more comprehensive maps of the cerebral cortex (Tzourio-Mazoyer et al. 2002; Desikan et al. 2006; Cohen, Fair, et al. 2008; Cohen, Lombardo, et al. 2008; Eickhoff et al. 2011; Wang et al. 2012; Fan et al. 2014; Wig et al. 2014; Laumann Timothy et al. 2015; Figure 4.”

“Differences between conditions were tested by first performing separate ALE analyses for each condition and computing the voxel-wise difference between the ensuing ALE maps (cf. Eickhoff et al., 2011b).”

“MACM is based on assessing the brain-wise co-activation patterns of a seed region across a large number of data based neuroimaging results (Eickhoff et al., 2011; Laird et al., 2009b).”