Table 3.

The identified putative hubs in macaques, chimpanzees and humans and their structural and functional importance in literature.

Species	Hemi	Cortex[1]	Possible areas reported in literature[2]	Structural & functional importance in literature	Literature	Type of network
Macaques	Left	medial parietal cortex	PGm	PGm: components of the default mode network (DMN) PGm: top 10 (out of 383) in out- degree PGm: top 10% across four centrality measures	(Harriger et al., 2012; Kojima et al., 2009; Mantini et al., 2011; Modha and Singh, 2010)	PET, task fMRI, tracer
		inferior parietal cortex	PCi, 7a	7a: identified as a hub, 7a: a component of DMN PCi: identified as a hub	(Bezgin et al., 2012; Sporns et al., 2007; Vincent et al., 2007)	Tracer, rs- fMRI
		insular cortex	Ia,Ip, Iai	Iai: rich-club region	(Harriger et al., 2012)	Tracer
		medial prefrontal cortex	PFCm, 32, 24, 9	32, 24, 9: components of DMN 32: top 10 (out of 383) in in-degree and BC 24: top 10 in degree and BC 9: top 10 in out-degree 24: top 10% across four centrality measures 32: top 10% across four centrality measures	(Harriger et al., 2012; Mantini et al., 2011; Modha and Singh, 2010)	Task fMRI, tracer
		ventrolateral and orbitolateral prefrontal cortex	PFCvl , PFCol, 46d,46, 12, 12o,12l	46d: a component of DMN 46: identified as a hub 12: components of resting-state networks 46: top 10 in degree and BC 12o,12l: top 10 in in-degree PFCvl: identified as a hub 46: top 10% across four centrality measures	(Bezgin et al., 2012; Kojima et al., 2009; Mantini et al., 2011; Modha and Singh, 2010; Sporns et al., 2007)	Task fMRI, tracer, PET
		primary visual cortex	V1	a component of resting-state networks	(Hutchison et al., 2011)	Rs-fMRI
	right	medial parietal cortex	PGm	PGm: components of DMN PGm: top 10 (out of 383) in out- degree PGm: top 10% across four centrality measures	(Harriger et al., 2012; Kojima et al., 2009; Mantini et al., 2011; Modha and Singh, 2010)	PET, task fMRI, tracer
		inferior parietal cortex	PCi,7a	7a: identified as a hub, 7a: a component of DMN PCi: identified as a hub	(Bezgin et al., 2012; Sporns et al., 2007; Vincent et al., 2007)	Tracer, rs- fMRI
		insular cortex	Ia,Ip, Iai	Iai: rich-club region	(Harriger et al., 2012)	Tracer
		medial prefrontal cortex	PFCm, 32, 24,9	32, 24, 9: components of DMN 32: top 10 in in-degree and BC 24: top 10 in degree and BC 9: top 10 in out-degree 24: top 10% across four centrality measures 32: top 10% across four centrality measures	(Harriger et al., 2012; Mantini et al., 2011; Modha and Singh, 2010)	Task fMRI, tracer
		ventrolateral and orbitolateral prefrontal cortex	PFCvl, PFCol, 46d,46, 12, 12o, 12l	46d: components of DMN 46: identified as a hub 12: components of resting-state networks 46: top 10 (out of 383) in degree and BC 12o,12l: top 10 in in-degree PFCvl: identified as a hub 46: top 10% across four centrality measures	(Bezgin et al., 2012; Kojima et al., 2009; Mantini et al., 2011; Modha and Singh, 2010; Sporns et al., 2007)	Task fMRI, tracer, PET
		primary and secondary visual cortex	V1,V2	Component of resting-state networks V2: top 10 in out-degree	(Hutchison et al., 2011; Modha and Singh, 2010)	Rs-fMRI, tracer
Chimpanzee	Left	medial parietal cortex	PCm	Components of resting-state networks	(Rilling et al., 2007)	PET
		inferior parietal cortex	PCi	Components of resting-state networks	(Rilling et al., 2007)	PET
		insular cortex	Ia, Ip
		medial prefrontal cortex	PFCm	Components of resting-state networks	(Rilling et al., 2007)	PET
		ventrolateral, polar prefrontal cortex	PFCvl, PFCpol	Components of resting-state networks	(Rilling et al., 2007)	PET
		primary visual cortex	V1
	right	medial parietal cortex	PCm	Components of resting-state networks	(Rilling et al., 2007)	PET
		inferior parietal cortex	PCi	Components of resting-state networks	(Rilling et al., 2007)	PET
		insular cortex	Ia, lp
		medial prefrontal cortex	PFCm	Components of resting-state networks	(Rilling et al., 2007)	PET
		ventrolateral, polar prefrontal cortex	PFCvl, PFCpol	Components of resting-state networks	(Rilling et al., 2007)	PET
		Primary visual cortex	V1
Humans	Left	medial parietal cortex	PCm, PCUN	Components of DMN PCUN: ranked top 25% in degrees and BC PCm: rich-club region	(Gong et al., 2009; Greicius et al., 2003; Hagmann et al., 2008; Li et al., 2012)	Task & rs- fMRI; diffusion MRI
		intraparietal sulcus and superior parietal cortex	PCip, PCs, SP	SP: the top 25% in BC SP: rich-club region	(Hagmann et al., 2008) (van den Heuvel et al., 2011)	Diffusion MRI
		insular cortex	Ia,Ip,	The top 10% in BC	(Iturria-Medina et al., 2008)	Diffusion MRI
		medial premotor cortex	PMCm, SFG	SFG: identified as a hub	(Gong et al., 2009)	Diffusion MRI
		primary motor cortex	M1
		retrosplenial cingulate cortex	CCr, ISTC	ISTC: top 25% in degree and BC	(Hagmann et al., 2008)	Diffusion MRI
	right	medial parietal cortex	PCm, PCUN	Components of DMN PCUN: ranked top 25% in degrees and BC PCm: rich-club region	(Gong et al., 2009; Greicius et al., 2003; Hagmann et al., 2008; Li et al., 2012)	Task & rs- fMRI; diffusion MRI
		intraparietal sulcus and superior parietal cortex	PCip, PCs, SP	SP: the top 25% in BC SP: rich-club region	(Hagmann et al., 2008) (van den Heuvel and Sporns, 2011)	Diffusion MRI
		insular cortex	Ia,Ip,	The top 10% in BC	(Iturria-Medina et al., 2008)	Diffusion MRI
		medial premotor cortex	PMCm, SFG	SFG: identified as a hub	(Gong et al., 2009)	Diffusion MRI
		primary motor cortex	M1
		retrosplenial cingulate cortex	CCr, ISTC	ISTC: top 25% in degree and BC	(Hagmann et al., 2008)	Diffusion MRI

¹The nomenclature for cortical areas is based on the study by Kotter et al., (Kotter and Wanke, 2005)

²For areas studied in literature, the abbreviations in Kotter et al., were first used, followed by the abbreviations in the related literature. For the full names of these abbreviations other than these from Kotter’s work, they are as follows: PCUN: precuneus; SP: superior parietal cortex; SFG: superior frontal gyrus; ISTC: isthmus of the cingulate cortex.